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Path: senator-bedfellow.mit.edu!enterpoop.mit.edu!usc!cs.utexas.edu!uunet!news.claremont.edu!ucivax!news.service.uci.edu!nntpsrv From: iglesias@draco.acs.uci.edu (Mike Iglesias) Subject: Rec.Bicycles Frequently Asked Questions Posting Part 4/4 Nntp-Posting-Host: draco.acs.uci.edu Expires: 20 Jul 93 00:00:00 GMT Message-ID: <rec-bicycles-faq-4_930614@draco.acs.uci.edu> Newsgroups: rec.bicycles.misc,news.answers,rec.answers Approved: news-answers-request@MIT.Edu Organization: University of California, Irvine Lines: 1225 Supersedes: <rec-bicycles-faq-4_930418@draco.acs.uci.edu> References: <rec-bicycles-faq-1_930614@draco.acs.uci.edu> Date: 15 Jun 93 03:39:09 GMT Followup-To: rec.bicycles.misc Xref: senator-bedfellow.mit.edu rec.bicycles.misc:5557 news.answers:9405 rec.answers:1193 Archive-name: bicycles-faq/part4 [Note: The complete FAQ is available via anonymous ftp from draco.acs.uci.edu (128.200.34.12), in pub/rec.bicycles.] --------------------------------------------------------------------------- Nancy's Cold/Wet Cycling Tips (Nancy Piltch piltch@ariel.lerc.nasa.gov) Here are some clothing suggestions, mix and match as you wish: Rain gear : I forked out the dollars for gore-tex when I did a week tour ... and I'm real glad I did. The stuff works reasonably as claimed, waterproof, and relatively breathable. (When the humidity is high, no fabric will work completely at letting sweat evaporate.) Unfortunately, typical prices are high. There are cheaper rainsuits, which I haven't tried. For short rides, or when the temperature is over about 50F, I don't usually wear the rain pants, as wet legs don't particularly bother me. Waterproof shoe covers. When the weather gets icky, I give up on the cleats (I'm not riding for performance then, anyway) and put the old-style pedals back on. This is basically because of the shoe covers I have that work better with touring shoes. The ones I have are made by Burley, and are available from Bikecentennial, though I got them at a local shop. They are just the cover, no insulation. I continue to use them in winter since they are windproof, and get the insulation I need from warm socks. These aren't neoprene, but rather some high-tech waterproof fabric. Gaiters that hikers and cross-country skiers wear can help keep road spray off your legs and feet. Toe clip covers. I got them from Nashbar; they are insulated and fit over the toe clips ... another reason for going back to those pedals. They help quite a bit when the temperature goes into the 30's and below; they are too warm above that. For temperatures in the 40's I usually find that a polypropylene shirt, lightweight sweater (mine is polypro) and wind shell work well; I use the gore-tex jacket, since I have it, but any light weight jacket is OK. I have a lightweight pair of nylon-lycra tights, suitable in the 50's, and maybe the 40's; a heavier pair of polypro tights, for 40's, and a real warm pair of heavy, fleece-lined tights for colder weather. (I have been comfortable in them down to about 15-deg, which is about the minimum I will ride in.) My tights are several years old, and I think there are lots more variations on warm tights out now. I use thin polypro glove liners with my cycling gloves when it is a little cool; lightweight gloves for a little bit cooler; gore-tex and thinsulate gloves for cold weather (with the glove liners in the really cold weather.) It is really my fingers that limit my cold weather riding, as anything any thicker than that limits my ability to work brake levers. (Note: this may change this year as I've just bought a mountain bike; the brake levers are much more accessible than on my road bike. It may be possible to ride with warm over-mitts over a wool or similar glove.) When it gets down to the 20's, or if it's windy at warmer (!) temperatures, I'll add the gore-tex pants from my rain suit, mostly as wind protection, rather than rain protection. Cheaper wind pants are available (either at bike shops or at sporting goods stores) that will work just as well for that use. Warm socks. There are lots of choices; I use 1 pair of wool/polypropylene hiking socks (fairly thick). Then with the rain covers on my shoes to keep out wind, and (if necessary) the toe clip covers, I'm warm enough. There are also thin sock liners, like my glove liners, but I haven't needed them; there are also neoprene socks, which I've never tried, and neoprene shoe covers, which I've also never tried, and wool socks, and ski socks ... I have a polypropylene balaclava which fits comfortably under my helmet; good to most of the temperatures I'm willing to ride in; a little too warm for temperatures above freezing, unless it's also windy. I also have an ear-warmer band, good for 40's and useful with the balaclava for miserable weather. I also have a neoprene face mask; dorky looking, but it works. It is definitely too hot until the temperature (or wind) gets severe. I sometimes add ski goggles for the worst conditions, but they limit peripheral vision, so I only use them if I'm desperate. For temperatures in the 30's, and maybe 20's, I wear a polarfleece pullover thing under the outer shell. Combining that with or without polypro (lightweight) sweater or serious duty wool sweater gives a lot of options. Sometimes I add a down vest -- I prefer it *outside* my shell (contrary to usual wisdom) because I usually find it too warm once I start moving and want to unzip it, leaving the wind shell closed for wind protection. I only use the down vest when it's below about 15 F. --------------------------------------------------------------------------- Studded Tires (Nancy Piltch piltch@ariel.lerc.nasa.gov) [A summary on studded tires compiled by Nancy. A complete copy of the responses she received, including some that give directions for making your own studded tires, is in the archive.] Studded tires do help, especially on packed snow and ice. On fresh snow and on water mixed with snow (i.e. slush) they're not significantly different from unstudded knobbies. On dry pavement they are noisy and heavy, but can be used; watch out for cornering, which is degraded compared to unstudded tires. Several people recommend a Mr. Tuffy or equivalent with them; one respondent says he gets more flats with a liner than without. In the U.S. the IRC Blizzard tires are commercially available. They can also be made. --------------------------------------------------------------------------- Cycling Myths Following are various myths about cycling and why they are/aren't true. Myth: Wearing a helmet makes your head hotter than if you didn't wear one. Actual measurements under hard riding conditions with ANSI standard helmets show no consistent temperature difference from helmetless riders. Part of the reason is that helmets provide insulated protection from the sun as well as some airflow around the head. (Les Earnest Les@cs.Stanford.edu) Myth: You need to let the air out of your tires before shipping your bike on an airplane - if you don't, the tires will explode. Assume your tire at sea level, pumped to 100 psi. Air pressure at sea level is (about) 15psi. Therefore, the highest pressure which can be reached in the tire is 100+15=115psi. Ergo: There is no need to deflate bicycle tires prior to flight to avoid explosions. (Giles Morris gilesm@bird.uucp) Addendum: The cargo hold is pressurized to the same pressure as the passenger compartment. (Tom ? tom@math.ufl.edu) Myth: You can break a bike lock with liquid nitrogen or other gases Freon cannot cool the lock sufficiently to do any good. Steel conducts heat into the cooling zone faster than it can be removed by a freeze bomb at the temperatures of interest. Liquid nitrogen or other gasses are so cumbersome to handle that a lock on a bike cannot be immersed as it must be to be effective. The most common and inconspicuous way to break these locks is by using a 4 inch long 1 inch diameter commercial hydraulic jack attached to a hose and pump unit. (Jobst Brandt jobst_brandt%01@hp1900.desk.hp.com) [More myths welcome!] --------------------------------------------------------------------------- Descending I (Roger Marquis marquis@well.sf.ca.us) Descending ability, like any other skill, is best improved with practice. The more time you can spend on technical descents the more confidence and speed you will be able to develop. A few local hot shots I know practice on their motorcycles before races with strategic descents. While frequent group rides are the only way to develop real bike handling skills descending with others will not necessarily help you descend faster alone. The most important aspect of fast descending is relaxation. Too much anxiety can narrow your concentration and you will miss important aspects of the road surface ahead. Pushing the speed to the point of fear will not help develop descending skills. Work on relaxation and smoothness (no sudden movements, braking or turning) and the speed will follow. A fast descender will set up well in advance of the corner on the outside, do whatever braking needs to be done before beginning to turn, hit the apex at the inside edge of the road, finally exiting again on the outside (always leaving some room for error or unforeseen road hazard). The key is to _gradually_ get into position and _smoothly_ follow your line through the corner. If you find yourself making _any_ quick, jerky movements take them as a sign that you need to slow down and devote a little more attention further up the road. Use your brakes only up to the beginning of a corner, NEVER USE THE BRAKES IN A CORNER. At that point any traction used for braking significantly reduces the traction available for cornering. If you do have to brake after entering the curve straighten out your line before applying the brakes. If the road surface is good use primarily the front brake. If traction is poor switch to the rear brake and begin breaking earlier. In auto racing circles there are two schools of thought on braking technique. One advocates gradually releasing the brakes upon entering the corner, the other advises hard braking right up to the beginning of the curve and abruptly releasing the brakes just before entering the curve. A cyclists would probably combine the techniques depending on the road surface, rim trueness, brake pad hardness and the proximity of other riders. Motorcyclists and bicyclists lean their bikes very differently in a corner. When riding fast motorcyclists keep their bikes as upright as possible to avoid scraping the bike. Bicyclists on the other hand lean their bikes into the corner and keep the body upright. Both motorcyclists and bicyclists extend the inside knee down to lower the center of gravity. To _pedal_ through the corners make like a motorcyclists and lean the bike up when the inside pedal is down. One of the most difficult things about descending in a group is passing. It is not always possible to begin the descent ahead of anyone who may be descending slower. If you find yourself behind someone taking it easy either hang out a safe distance behind or pass very carefully. Passing on a descent is always difficult and dangerous. By the same token, if you find yourself ahead of someone who obviously wants to pass, let them by at the earliest safe moment. It's never appropriate to impede someone's progress on a training ride whether they are on a bicycle or in a car. Always make plenty of room for anyone trying to pass no matter what the speed limit may be. Be courteous and considerate and you'll be forever happy. Remember that downhill racing is not what bicycle racing is all about. There is no need to keep up with the Jones'. This is what causes many a crash. Compete against yourself on the descents. Belgians are notoriously slow descenders due to the consistently rainy conditions there. Yet some of the best cyclists in the world train on those rainy roads. Don't get caught pushing it on some wet or unfamiliar descent. Be prepared for a car or a patch of dirt or oil in the middle of your path around _every_ blind corner no matter how many times you've been on a particular road. Take it easy, relax, exercise your powers of concentration and hammer again when you can turn the pedals. If you're interested in exploring this further the best book on bike handling I've read is "Twist of The Wrist" by motorcycle racer Keith Code. There is also data out there (Cycle Magazine) on eye exercises designed to train depth perception adjustment, peripheral vision and concentration. If you know where I can find this information please send it to: NCNCA District Coaching Office Roger Marquis 782 San Luis Rd. Berkeley, Ca 94707 --------------------------------------------------------------------------- Descending II (Jobst Brandt jobst_brandt@hplabs.hp.com) The Art of Descending (an assessment) Descending on a bicycle requires a combination of skills that are more commonly used in motorcycling. Only when descending does the bicycle have the power and speed that the motorcycle encounters regularly, not to say that criterium racing doesn't also challenge these skills. It requires a combination of lean angle and braking while selecting an appropriate line through curves. Unlike motorcycle tires, bicycle tires have little margin and even a small slip on pavement is usually unrecoverable. Understanding the forces involved and how to control them is more natural to some than others. For some these skills may have atrophied from disuse at an early age and need to be regenerated. How to Corner Cornering is the skill of anticipating the appropriate lean angle with respect to the ground before you get to the apex of the turn. The angle is what counts and it is limited by traction. This means you must have an eye for traction. For most pavement this is about 45 degrees in the absence of oil, water or other smooth and slick spots. So if the curve is banked 10 degrees, you could lean to 55 degrees from the vertical. In contrast, a crowned road with no banking, where the surface falls off about 10 degrees, would allow only 35 degrees (at the limit). Estimating the required lean angle for a curve is derived from the apparent traction and what your speed will be in the apex of the turn at the current rate of braking. Anticipating the lean angle is something humans, animals and birds do regularly in self propulsion. When running you anticipate how fast and sharply you can turn on the sidewalk, dirt track or lawn on which you run. You estimate the lean for the conditions and you control your speed to not exceed that angle. Although the consequences are more severe, the same is true for the bicycle. These are reflexes that are normal to most people in youth but some have not exercised them in such a long time that they don't trust their skills. A single fall strongly reinforces this doubt. For this reason, it is best to improve and regenerate these abilities gradually through practice. Braking Once the nuts and bolts of getting around a corner are in place the big difference between being fast and being faster is another problem entirely. First it must be understood that braking is a primary skill that is greatly misunderstood. When traction is good, the front brake should be used almost exclusively because, with it, the bike can slow down so rapidly that the back wheel lifts off the road. When slowing down at this rate the rear brake is obviously useless. Once you enter the curve, more and more traction is used by the lean angle but braking is still used to trim speed. This is done with both brakes because neither wheel has much additional traction to give. It is good to practice hard front braking at a low and safe speed to develop a feel for rear wheel lift-off. You may ask why you should be braking in the turn. If you do all your braking before the turn you will be going too slowly too early. Because it is practically impossible to anticipate the exact maximum speed for the apex of the turn, you should anticipate braking in the turn. Fear of braking usually comes from an incident caused by injudicious braking. How you use the front and rear brake must be adapted to various conditions. When riding straight ahead with good traction, you can safely allow substantial transfer of weight from the rear to the front wheel allowing strong use of the front brake. When traction is poor, deceleration and weight transfer is small, so light braking with both wheels is appropriate. If traction is miserable, you should use only the rear brake because, although a rear skid is permissible, one in the front is not. Take for example a rider cornering on good traction, banked over at 45 degrees. With 1 G centrifugal acceleration, he can still apply the brakes at 0.1 G. The increases in side force on the wheels is given by the square root(1^2+0.1^2)=1.005. In other words, you can do appreciable braking while at maximum cornering. The centrifugal acceleration is also reduced by the square of the speed by which the lean angle rapidly reduces. Being aware of this relationship should leave no doubt about why racers are often seen pulling their brake levers in max speed turns. Suspension Beyond lean and braking, suspension helps immeasurably in descending. For bicycles without built-in suspension, this is furnished by your legs. If the road has fine ripples you needn't stand up but merely take the weight off your pelvic bones. For rougher roads, you should rise high enough so the saddle does not carry any weight. The reason for this is twofold. Your vision will become blurred if you don't rise off the saddle, and traction will be compromised by momentary overloads while skipping over bumps. The ideal is to keep the tire on the ground at uniform load. Some riders believe that sticking out their knee or leaning their body away from the bike, improves cornering. Sticking out a knee is the same thing that riders without cleats do when they stick out a foot, it is a useless but reassuring gesture that, on uneven roads, actually works against you. Any body weight that is not centered on the bicycle (leaning the bike or sticking out a knee) puts a side load on the bicycle, and side loads cause steering motions if the road is not smooth. To verify this, ride down a straight but rough road standing on one pedal with the bike slanted, and note how the bike follows an erratic course. In contrast, if you ride centered on the bike you can ride no-hands perfectly straight over rough road. When you lean off the bike you cannot ride a smooth line over road irregularities, especially in curves. For best control, stay centered over your bike. Vision Where you look is critical to effective descending. Your central vision involves mostly the cones in the retina of your eye. These are color receptive and images generally are more time consuming to interpret than information received by the rods in the peripheral vision. For this reason you should focus on the pavement where your tire will track while looking for obstacles and possible oncoming traffic in your peripheral vision that is fast and good at detecting motion. If you look at the place where an oncoming vehicle or obstacle might appear, its appearance will bring data processing to a halt for a substantial time. You needn't identify the color or model of car so leave it to the peripheral vision in high speed black and white because processing speed is essential. The Line Picking the broadest curve through a corner should be obvious by the time the preceding skills are mastered but the line is both a matter of safety and road surface. Sometimes it is better to hit a bump or a "Bott's dot" than to alter the line, especially at high speed. In that respect, your tire should be large enough to absorb the entire height of a "Bott's dot" without pinching the tube. Mental Speed Mental speed is demanded by all of these and, it is my experience, those who are slow to grasp an idea, do not have good hand-eye coordination, or are "accident prone", should be extra cautious in this. In contrast, being quick does not guarantee success either. Above all, it is important to not be daring but rather to ride with a margin that leaves a comfortable feeling rather than one of high risk. At the same time, do not be blinded by the age old presumption that everyone who rides faster than I is crazy. It is one of the most common descriptions used by a slower observer. "He descended like a madman!" means merely that the speaker was slower, nothing more. Ride bike! --------------------------------------------------------------------------- Trackstands (Rick Smith ricks@sdd.hp.com) How to trackstand on a road bike. With acknowledgments to my trackstanding mentor, Neil Bankston. Practice, Practice, Practice, Practice, .... 1. Wear tennis shoes. 2. Find an open area, like a parking lot that has a slight grade to it. 3. Put bike in a gear around a 42-18. 4. Ride around out of the saddle in a counter-clockwise circle, about 10 feet in diameter. Label Notation for imaginary points on the circle: 'A' is the lowest elevation point on the circle. 'B' is the 90 degrees counterclockwise from 'A' . 'C' is the highest elevation point on the circle. 'D' is the 90 degrees counterclockwise from 'C' . C / \ D B Aerial View \ / A 5. Start slowing down, feeling the different sensation as the bike transitions between going uphill (B) and downhill (D). 6. Start trying to go real slowly through the A - B region of the circle. This is the region you will use for trackstanding. Ride the rest of the circle as you were in step 5. The trackstanding position (aerial view again): ---| / ------| |----/ |--- / The pedal are in a 3 o'clock - 9 o'clock arrangement (in other words, parallel to the ground). Your left foot is forward, your wheel is pointed left. You are standing and shifting you weight to keep balance. The key to it all is this: If you start to fall left, push on the left peddle to move the bike forward a little and bring you back into balance. If you start to fall right, let up on the peddle and let the bike roll back a little and bring you back into balance. 7. Each time you roll through the A - B region, try to stop when the left peddle is horizontal and forward. If you start to lose your balance, just continue around the circle and try it again. 8. Play with it. Try doing it in various regions in the circle, with various foot position, and various amounts of turn in your steering. Try it on different amounts of slope in the pavement. Try different gears. What you are shooting for is the feel that's involved, and it comes with practice. The why's of trackstanding: Why is road bike specified in the title? A true trackstand on a track bike is done differently. A track bike can be peddled backwards, and doesn't need a hill to accomplish the rollback affect. Track racing trackstands are done opposite of what is described. They take place on the C - D region of the circle, with gravity used for the roll forward, and back pedaling used for the rollback. This is so that a racer gets the assist from gravity to get going again when the competition makes a move. Why a gear around 42-18? This is a reasonable middle between too small, where you would reach the bottom of the stroke on the roll forward, and too big, where you couldn't generate the roll forward force needed. Why is the circle counter-clockwise? Because I assume you are living in an area where travel is done on the right side of the road. When doing trackstands on the road, most likely it will be at traffic lights. Roads are crowned - higher in the middle, lower on the shoulders - and you use this crown as the uphill portion of the circle (region A-B). If you are in a country where travel is done on the left side of the road, please interpret the above aerial views as subterranial. Why is this done out of the saddle? It's easier!! It can be done in while seated, but you lose the freedom to do weight adjustments with your hips. Why is the left crank forward? If your right crank was forward, you might bump the front wheel with your toe. Remember the steering is turned so that the back of the front wheel is on the right side of the bike. Some bikes have overlap of the region where the wheel can go and your foot is. Even if your current bike doesn't have overlap, it's better to learn the technique as described in case you are demonstrating your new skill on a bike that does have overlap. Why the A - B region? It's the easiest. If you wait till the bike is around 'B', then you have to keep more force on the peddle to hold it still. If you are around the 'A' point, there may not be enough slope to allow the bike to roll back. Questions: What do I do if I want to stop on a downhill? While there are techniques that can be employed to keep you in the pedals, for safety sake I would suggest getting out of the pedals and putting your foot down. Other exercises that help: Getting good balance. Work through this progression: 1. Stand on your right foot. Hold this until it feels stable. 2. Close your eyes. Hold this until it feels stable. 3. Go up on your toes. Hold this until it feels stable. 4. If you get to here, never mind, your balance is already wonderful, else repeat with other foot. --------------------------------------------------------------------------- Front Brake Usage (John Forester jforester@cup.portal.com) I have dealt for many years with the problem of explaining front brake use, both to students and to courtrooms, and I have reached some conclusions, both about the facts and about the superstitions. The question was also asked about British law and front brakes. I'll answer that first because it is easier. British law requires brakes on both wheels, but it accepts that a fixed gear provides the required braking action on the rear wheel. I think that the requirement was based on reliability, not on deceleration. That is, if the front brake fails, the fixed-gear cyclist can still come to a stop. In my house (in California) we have three track-racing bikes converted to road use by adding brakes. Two have only front brakes while the third has two brakes. We have had no trouble at all, and we ride them over mild hills. The front-brake-only system won't meet the normal U.S. state traffic law requirement of being able to skid one wheel, because that was written for coaster-braked bikes, but it actually provides twice the deceleration of a rear-wheel-braked bike and nobody, so far as I know, has ever been prosecuted for using such a setup. The superstitions about front brake use are numerous. The most prevalent appears to be that using the front brake without using the rear brake, or failing to start using the rear brake before using the front brake, will flip the cyclist. The other side of that superstition is that using the rear brake will prevent flipping the bicycle, regardless of how hard the front brake is applied. The truth is that regardless of how hard the rear brake is applied, or whether it is applied at all, the sole determinant (aside from matters such as bicycle geometry, weight and weight distribution of cyclist and load, that can't practically be changed while moving) of whether the bicycle will be flipped is the strength of application of the front brake. As the deceleration to produce flip is approached, the weight on the rear wheel decreases to zero, so that the rear wheel cannot produce any deceleration; with no application of the rear brake it rolls freely, with any application at all it skids at a force approaching zero. With typical bicycle geometry, a brake application to attempt to produce a deceleration greater than 0.67 g will flip the bicycle. (Those who advocate the cyclist moving his butt off and behind the saddle to change the weight distribution achieve a very small increase in this.) A typical story is that of a doctor who, now living in the higher- priced hilly suburbs, purchased a new bicycle after having cycled to med school on the flats for years. His first ride was from the bike shop over some minor hills and then up the 15% grade to his house. His second ride was down that 15% grade. Unfortunately, the rear brake was adjusted so that it produced, with the lever to the handlebar, a 0.15 g deceleration. The braking system would meet the federal requirements of 0.5 g deceleration with less than 40 pounds grip on the levers, because the front brake has to do the majority of the work and at 0.5 g there is insufficient weight on the rear wheel to allow much more rear brake force than would produce 0.1 g deceleration. (The U.S. regulation allows bicycles with no gear higher than 60 inches to have only a rear-wheel brake that provides only 0.27 g deceleration.) I don't say that the rear brake adjustment of the bicycle in the accident was correct, because if the front brake fails then the rear brake alone should be able to skid the rear wheel, which occurs at about 0.3 g deceleration. The doctor starts down the hill, coasting to develop speed and then discovering that he can't slow down to a stop using the rear brake alone. That is because the maximum deceleration produced by the rear brake equalled, almost exactly, the slope of the hill. He rolls down at constant speed with the rear brake lever to the handlebar and the front brake not in use at all. He is afraid to apply the front brake because he fears that this will flip him, but he is coming closer and closer to a curve, after which is a stop sign. At the curve he panics and applies the front brake hard, generating a force greater than 0.67 g deceleration and therefore flipping himself. Had he applied the front brake with only a force to produce 0.1 g deceleration, even 100 feet before the curve, he would have been safe, but in his panic he caused precisely the type of accident that he feared. He thought that he had a good case, sued everybody, and lost. This is the type of superstition that interferes with the cycling of many people. My standard instruction for people who fear using the front brake is the same instruction for teaching any person to brake properly. Tell them to apply both brakes simultaneously, but with the front brake 3 times harder than the rear brake. Start by accelerating to road speed and stopping with a gentle application. Then do it again with a harder application, but keeping the same 3 to 1 ratio. Then again, harder still, until they feel the rear wheel start to skid. When the rear wheel skids with 1/4 of the total braking force applied to it, that shows that the weight distribution has now progressed as far to the front wheel as the average cyclist should go. By repeated practice they learn how hard this is, and attain confidence in their ability to stop as rapidly as is reasonable without any significant risk. --------------------------------------------------------------------------- Slope Wind, the Invisible Enemy (Jobst Brandt jobst_brandt@hplabs.hp.com) Wind as well as relative wind caused by moving through still air demands most of a bicyclists effort on level ground. Most riders recognize when they are subjected to wind because it comes in gusts and these gusts can be distinguished from the more uniform wind caused by moving through still air. That's the catch. At the break of dawn there is often no wind as such but cool air near the ground, being colder and more dense than higher air slides downslope as a laminar layer that has no turbulent gusts. Wind in mountain valleys generally blows uphill during the heat of the day and therefore pilots of light aircraft are warned to take off uphill against the morning slope wind. Slope wind, although detectable, is not readily noticed when standing or walking because it has negligible effect and does not come in apparent gusts. The bicyclist, in contrast, is hindered by it but cannot detect it because there is always wind while riding. Slope wind, as such, can be up to 10 mph before it starts to take on the characteristics that we expect of wind. It is doubly deceptive when it comes from behind because it gives an inflated speed that can be mistakenly attributed to great fitness that suddenly vanishes when changing course. If you live near aspen or poplars that tend to fan their leaves in any breeze, you will not be fooled. --------------------------------------------------------------------------- Reflective Tape (Jobst Brandt jobst_brandt@hplabs.hp.com) Reflective tape is available in most better bike shops in various forms, most of which is pre-cut to some preferred shape and designed for application to some specific part of the bike or apparel. The most effective use of such tape is on moving parts such as pedals, heel of the shoe or on a place that is generally overlooked, the inside of the rim. First, it is appropriate to note that car headlights generally produce white light and a white or, in fact, colorless reflector returns more of this light to its source than ones with color filters or selective reflection. Red, for instance, is not nearly as effective as white. Placing reflective tape on the inside of the rims between the spokes is a highly effective location for night riding because it is visible equally to the front and rear while attracting attention through its motion. It is most effective when applied to less than half the rim in a solid block. Five inter-spoke sections does a good job. One can argue that it isn't visible from the side (if the rim is not an aero cross section) but the major hazard is from the front and rear. Be seen on a bike! It's good for your health. --------------------------------------------------------------------------- Nutrition (Bruce Hildenbrand bhilden@unix386.Convergent.COM) Oh well, I have been promising to do this for a while and given the present discussions on nutrition, it is about the right time. This article was written in 1980 for Bicycling Magazine. It has been reprinted in over 30 publications, been the basis for a chapter in a book and cited numerous other times. I guess somebody besides me thinks its OK. If you disagree with any points, that's fine, I just don't want to see people take exception based on their own personal experiences because everyone is different and psychological factors play a big role(much bigger than you would think) on how one perceives his/her own nutritional requirements. Remember that good nutrition is a LONG TERM process that is not really affected by short term events(drinking poison would be an exception). If it works for you then do it!!! Don't preach!!!! BASIC NUTRITION PRIMER Nutrition in athletics is a very controversial topic. However, for an athlete to have confidence that his/her diet is beneficial he/she must understand the role each food component plays in the body's overall makeup. Conversely, it is important to identify and understand the nutritional demands on the physiological processes of the body that occur as a result of racing and training so that these needs can be satisfied in the athlete's diet. For the above reasons, a basic nutrition primer should help the athlete determine the right ingredients of his/her diet which fit training and racing schedules and existing eating habits. The body requires three basic components from foods: 1) water; 2) energy; and 3)nutrients. WATER Water is essential for life and without a doubt the most important component in our diet. Proper hydrations not only allows the body to maintain structural and biochemical integrity, but it also prevents overheating, through sensible heat loss(perspiration). Many cyclists have experienced the affects of acute fluid deficiency on a hot day, better known as heat exhaustion. Dehydration can be a long term problem, especially at altitude, but this does not seem to be a widespread problem among cyclists and is only mentioned here as a reminder(but an important one). ENERGY Energy is required for metabolic processes, growth and to support physical activity. The Food and Nutrition Board of the National Academy of Sciences has procrastinated in establishing a Recommended Daily Allowance(RDA) for energy the reasoning being that such a daily requirement could lead to overeating. A moderately active 70kg(155lb) man burns about 2700 kcal/day and a moderately active 58kg(128lb) woman burns about 2500 kcal/day. It is estimated that cyclists burn 8-10 kcal/min or about 500-600 kcal/hr while riding(this is obviously dependent on the level of exertion). Thus a three hour training ride can add up to 1800 kcals(the public knows these as calories) to the daily energy demand of the cyclist. Nutritional studies indicate that there is no significant increase in the vitamin requirement of the athlete as a result of this energy expenditure. In order to meet this extra demand, the cyclist must increase his/her intake of food. This may come before, during or after a ride but most likely it will be a combination of all of the above. If for some reason extra nutrients are required because of this extra energy demand, they will most likely be replenished through the increased food intake. Carbohydrates and fats are the body's energy sources and will be discussed shortly. NUTRIENTS This is a broad term and refers to vitamins, minerals, proteins, carbohydrates, fats, fiber and a host of other substances. The body is a very complex product of evolution. It can manufacture many of the resources it needs to survive. However, vitamins, minerals and essential amino acids(the building blocks of proteins) and fatty acids cannot be manufactured, hence they must be supplied in our food to support proper health. Vitamins and Minerals No explanation needed here except that there are established RDA's for most vitamins and minerals and that a well balanced diet, especially when supplemented by a daily multivitamin and mineral tablet should meet all the requirements of the cyclist. Proper electrolyte replacement(sodium and potassium salts) should be emphasized, especially during and after long, hot rides. Commercially available preparations such as Exceed, Body Fuel and Isostar help replenish electrolytes lost while riding. Proteins Food proteins are necessary for the synthesis of the body's skeletal(muscle, skin, etc.) and biochemical(enzymes, hormones, etc.)proteins. Contrary to popular belief, proteins are not a good source of energy in fact they produce many toxic substances when they are converted to the simple sugars needed for the body's energy demand. Americans traditionally eat enough proteins to satisfy their body's requirement. All indications are that increased levels of exercise do not cause a significant increase in the body's daily protein requirement which has been estimated to be 0.8gm protein/kg body weight. Carbohydrates Carbohydrates are divided into two groups, simple and complex, and serve as one of the body's two main sources of energy. Simple carbohydrates are better known as sugars, examples being fructose, glucose(also called dextrose), sucrose(table sugar) and lactose(milk sugar). The complex carbohydrates include starches and pectins which are multi-linked chains of glucose. Breads and pastas are rich sources of complex carbohydrates. The brain requires glucose for proper functioning which necessitates a carbohydrate source. The simple sugars are quite easily broken down to help satisfy energy and brain demands and for this reason they are an ideal food during racing and training. The complex sugars require a substantially longer time for breakdown into their glucose sub units and are more suited before and after riding to help meet the body's energy requirements. Fats Fats represent the body's other major energy source. Fats are twice as dense in calories as carbohydrates(9 kcal/gm vs 4 kcal/gm) but they are more slowly retrieved from their storage units(triglycerides) than carbohydrates(glycogen). Recent studies indicate that caffeine may help speed up the retrieval of fats which would be of benefit on long rides. Fats are either saturated or unsaturated and most nutritional experts agree that unsaturated, plant-based varieties are healthier. Animal fats are saturated(and may contain cholesterol), while plant based fats such as corn and soybean oils are unsaturated. Unsaturated fats are necessary to supply essential fatty acids and should be included in the diet to represent about 25% of the total caloric intake. Most of this amount we don't really realize we ingest, so it is not necessary to heap on the margarine as a balanced diet provides adequate amounts. WHAT THE BODY NEEDS Now that we have somewhat of an understanding of the role each food component plays in the body's processes let's relate the nutritional demands that occur during cycling in an attempt to develop an adequate diet. Basically our bodies need to function in three separate areas which require somewhat different nutritional considerations. These areas are: 1) building; 2) recovery; and 3) performance. Building Building refers to increasing the body's ability to perform physiological processes, one example being the gearing up of enzyme systems necessary for protein synthesis, which results in an increase in muscle mass, oxygen transport, etc. These systems require amino acids, the building blocks of proteins. Hence, it is important to eat a diet that contains quality proteins (expressed as a balance of the essential amino acid sub units present)fish, red meat, milk and eggs being excellent sources. As always, the RDA's for vitamins and minerals must also be met but, as with the protein requirement, they are satisfied in a well balanced diet. Recovery This phase may overlap the building process and the nutritional requirements are complimentary. Training and racing depletes the body of its energy reserves as well as loss of electrolytes through sweat. Replacing the energy reserves is accomplished through an increased intake of complex carbohydrates(60-70% of total calories) and to a lesser extent fat(25%). Replenishing lost electrolytes is easily accomplished through the use of the commercial preparations already mentioned. Performance Because the performance phase(which includes both training rides and racing)spans at most 5-7 hours whereas the building and recovery phases are ongoing processes, its requirements are totally different from the other two. Good nutrition is a long term proposition meaning the effects of a vitamin or mineral deficiency take weeks to manifest themselves. This is evidenced by the fact that it took many months for scurvy to show in sailors on a vitamin C deficient diet. What this means is that during the performance phase, the primary concern is energy replacement (fighting off the dreaded "bonk") while the vitamin and mineral demands can be overlooked. Simple sugars such a sucrose, glucose and fructose are the quickest sources of energy and in moderate quantities of about 100gm/hr(too much can delay fluid absorption in the stomach) are helpful in providing fuel for the body and the brain. Proteins and fats are not recommended because of their slow and energy intensive digestion mechanism. Short, one day rides or races of up to one hour in length usually require no special nutritional considerations provided the body's short term energy stores (glycogen) are not depleted which may be the case during multi-day events. Because psychological as well as physiological factors determine performance most cyclists tend to eat and drink whatever makes them feel "good" during a ride. This is all right as long as energy considerations are being met and the stomach is not overloaded trying to digest any fatty or protein containing foods. If the vitamin and mineral requirements are being satisfied during the building and recovery phases no additional intake during the performance phase is necessary. IMPLICATIONS Basically, what all this means is that good nutrition for the cyclist is not hard to come by once we understand our body's nutrient and energy requirements. If a balanced diet meets the RDA's for protein, vitamins and minerals as well as carbohydrate and fat intake for energy then everything should be OK nutritionally. It should be remembered that the problems associated with nutrient deficiencies take a long time to occur. Because of this it is not necessary to eat "right" at every meal which explains why weekend racing junkets can be quite successful on a diet of tortilla chips and soft drinks. However, bear in mind that over time, the body's nutritional demands must be satisfied. To play it safe many cyclists take a daily multivitamin and mineral supplement tablet which has no adverse affects and something I personally recommend. Mega vitamin doses(levels five times or more of the RDA) have not been proven to be beneficial and may cause some toxicity problems. GREY NUTRITION "Good" nutrition is not black and white. As we have seen, the body's requirements are different depending on the phase it is in. While the building and recovery phases occur somewhat simultaneously the performance phase stands by itself. For this reason, some foods are beneficial during one phase but not during another. A good example is the much maligned twinkie. In the performance phase it is a very quick source of energy and quite helpful. However, during the building phase it is not necessary and could be converted to unwanted fat stores. To complicate matters, the twinkie may help replenish energy stores during the recovery phase however, complex carbohydrates are probably more beneficial. So, "one man's meat may be another man's poison." NUTRIENT DENSITY This term refers to the quantity of nutrients in a food for its accompanying caloric(energy) value. A twinkie contains much energy but few vitamins and minerals so has a low nutrient density. Liver, on the other hand, has a moderate amount of calories but is rich in vitamins and minerals and is considered a high nutrient density food. Basically, one must meet his/her nutrient requirements within the constraints of his/her energy demands. Persons with a low daily activity level have a low energy demand and in order to maintain their body weight must eat high nutrient density foods. As already mentioned, a cyclist has an increased energy demand but no significant increase in nutrient requirements. Because of this he/she can eat foods with a lower nutrient density than the average person. This means that a cyclist can be less choosy about the foods that are eaten provided he/she realizes his/her specific nutrient and energy requirements that must be met. BALANCED DIET Now, the definition of that nebulous phrase, "a balanced diet". Taking into consideration all of the above, a diet emphasizing fruits and vegetables (fresh if possible), whole grain breads, pasta, cereals, milk, eggs, fish and red meat(if so desired) will satisfy long term nutritional demands. These foods need to be combined in such a way that during the building and recovery phase, about 60-70% of the total calories are coming from carbohydrate sources, 25% from fats and the remainder(about 15%) from proteins. It is not necessary to get 100% of the RDA for all vitamins and minerals at every meal. It may be helpful to determine which nutritional requirements you wish to satisfy at each meal. Personally, I use breakfast to satisfy part of my energy requirement by eating toast and cereal. During lunch I meet some of the energy, protein and to a lesser extent vitamin and mineral requirements with such foods as yogurt, fruit, and peanut butter and jelly sandwiches. Dinner is a big meal satisfying energy, protein, vitamin and mineral requirements with salads, vegetables, pasta, meat and milk. Between meal snacking is useful to help meet the body's energy requirement. CONCLUSION All this jiberish may not seem to be telling you anything you couldn't figure out for yourself. The point is that "good" nutrition is not hard to achieve once one understands the reasons behind his/her dietary habits. Such habits can easily be modified to accommodate the nutritional demands of cycling without placing any strict demands on one's lifestyle. --------------------------------------------------------------------------- Nuclear Free Energy Bar Recipe (Phil Etheridge phil@massey.ac.nz) Nuclear Free Energy Bars ~~~~~~~~~~~~~~~~~~~~~~~~ Comments and suggestions welcome. They seem to work well for me. I eat bananas as well, in about equal quanities to the Nuclear Free Energy Bars. I usually have two drink bottles, one with water to wash down the food, the other with a carbo drink. You will maybe note that there are no dairy products in my recipe -- that's because I'm allergic to them. You could easily replace the soy milk powder with the cow equivalent, but then you'd definitely have to include some maltodextrin (my soy drink already has some in it). I plan to replace about half the honey with maltodextrin when I find a local source. If you prefer cocoa to carob, you can easily substitute. C = 250 ml cup, T = 15 ml tablespoon 1 C Oat Bran 1/2 C Toasted Sunflower and/or Sesame seeds, ground (I use a food processor) 1/2 C Soy Milk Powder (the stuff I get has 37% maltodextrin, ~20% dextrose*) 1/2 C Raisins 2T Carob Powder Mix well, then add to 1/2 C Brown Rice, Cooked and Minced (Using a food processor again) 1/2 C Peanut Butter (more or less, depending on consistency) 1/2 C Honey (I use clear, runny stuff, you may need to warm if it's thicker and/or add a little water) Stir and knead (I knead in more Oat Bran or Rolled Oats) until thoroughly mixed. A cake mixer works well for this. The bars can be reasonably soft, as a night in the fridge helps to bind it all together. Roll or press out about 1cm thick and cut. Makes about 16, the size I like them (approx 1cm x 1.5cm x 6cm). * Can't remember exact name, dextrose something) --------------------------------------------------------------------------- Powerbars (John McClintic johnm@hammer.TEK.COM) Have you ever watched a hummingbird? Think about it! Hummingbirds eat constantly to survive. We lumpish earthbound creatures are in no position to imitate this. Simply, if we overeat we get fat. There are exceptions: those who exercise very strenuously can utilize - indeed, actually need - large amounts of carbohydrates. For example, Marathon runners "load" carbohydrates by stuffing themselves with pasta before a race. On the flip side Long-distance cyclists maintain their energy level by "power snacking". With reward to the cyclist and their need for "power snacking" I submit the following "power bar" recipe which was originated by a fellow named Bill Paterson. Bill is from Portland Oregon. The odd ingredient in the bar, paraffin, is widely used in chocolate manufacture to improve smoothness and flowability, raise the melting point, and retard deterioration of texture and flavor. Butter can be used instead, but a butter-chocolate mixture doesn't cover as thinly or smoothly. POWER BARS ---------- 1 cup regular rolled oats 1/2 cup sesame seed 1 1/2 cups dried apricots, finely chopped 1 1/2 cups raisins 1 cup shredded unsweetened dry coconut 1 cup blanched almonds, chopped 1/2 cup nonfat dry milk 1/2 cup toasted wheat germ 2 teaspoons butter or margarine 1 cup light corn syrup 3/4 cup sugar 1 1/4 cups chunk-style peanut butter 1 teaspoon orange extract 2 teaspoons grated orange peel 1 package (12 oz.) or 2 cups semisweet chocolate baking chips 4 ounces paraffin or 3/4 cup (3/4 lb.) butter or margarine Spread oats in a 10- by 15-inch baking pan. Bake in a 300 degree oven until oats are toasted, about 25 minutes. Stir frequently to prevent scorching. Meanwhile, place sesame seed in a 10- to 12-inch frying pan over medium heat. Shake often or stir until seeds are golden, about 7 minutes. Pour into a large bowl. Add apricots, raisins, coconut, almonds, dry milk, and wheat germ; mix well. Mix hot oats into dried fruit mixture. Butter the hot backing pan; set aside. In the frying pan, combine corn syrup and sugar; bring to a rolling boil over medium high heat and quickly stir in the peanut butter, orange extract, and orange peel. At once, pour over the oatmeal mixture and mix well. Quickly spread in buttered pan an press into an even layer. Then cover and chill until firm, at least 4 hours or until next day. Cut into bars about 1 1/4 by 2 1/2 inches. Combine chocolate chips and paraffin in to top of a double boiler. Place over simmering water until melted; stir often. Turn heat to low. Using tongs, dip 1 bar at a time into chocolate, hold over pan until it stops dripping (with paraffin, the coating firms very quickly), then place on wire racks set above waxed paper. When firm and cool (bars with butter in the chocolate coating may need to be chilled), serve bars, or wrap individually in foil. Store in the refrigerator up to 4 weeks; freeze to store longer. Makes about 4 dozen bars, about 1 ounce each. Per piece: 188 cal.; 4.4 g protein; 29 g carbo.; 9.8 g fat; 0.6 mg chol.; 40 mg sodium. --------------------------------------------------------------------------- Calories burned by cycling (Jeff Patterson jpat@hpsad.sad.hp.com) The following table appears in the '92 Schwinn ATB catalog which references Bicycling, May 1989: --------- Speed (mph) 12 14 15 16 17 18 19 Rider Weight Calories/Hr 110 293 348 404 448 509 586 662 120 315 375 437 484 550 634 718 130 338 402 469 521 592 683 773 140 360 430 502 557 633 731 828 150 383 457 534 593 675 779 883 160 405 485 567 629 717 828 938 170 427 512 599 666 758 876 993 180 450 540 632 702 800 925 1048 190 472 567 664 738 841 973 1104 200 495 595 697 774 883 1021 1159 (flat terrain, no wind, upright position) --------------------------------------------------------------------------- Road Rash Cures (E Shekita shekita@provolone.cs.wisc.edu) [Ed note: This is a condensation of a summary of cures for road rash that Gene posted.] The July 1990 issue of Bicycle Guide has a decent article on road rash. Several experienced trainers/doctors are quoted. They generally recommended: - cleaning the wound ASAP using an anti-bacterial soap such as Betadine. Showering is recommended, as running water will help flush out dirt and grit. If you can't get to a shower right away, at the very least dab the wound with an anti-bacteria solution and cover the wound with a non-stick telfa pad coated with bactrin or neosporin to prevent infection and scabbing. The wound can then be showered clean when you get home. It often helps to put an ice bag on the wound after it has been covered to reduce swelling. - after the wound has been showered clean, cover the wound with either 1) a non-stick telfa pad coated with bactrin or neosporin, or 2) one of the Second Skin type products that are available. If you go the telfa pad route, daily dressing changes will be required until a thin layer of new skin has grown over the wound. If you go the Second Skin route, follow the directions on the package. The general consensus was that scabbing should be prevented and that the Second Skin type products were the most convenient -- less dressing changes and they hold up in a shower. (Silvadene was not mentioned, probably because it requires a prescription.) It was pointed out that if one of the above treatments is followed, then you don't have to go crazy scrubbing out the last piece of grit or dirt in the wound, as some people believe. This is because most of the grit will "float" out of the wound on its own when a moist dressing is used. There are now products that go by the names Bioclusive, Tegaderm, DuoDerm, Op-Site, Vigilon, Spenco 2nd Skin, and others, that are like miracle skin. This stuff can be expensive ($5 for 8 3x4 sheets), but does not need to be changed. They are made of a 96% water substance called hydrogel wrapped in thin porous plastic. Two non-porous plastic sheets cover the hydrogel; One sheet is removed so that the hydrogel contacts the wound and the other non-porous sheet protects the wound. These products are a clear, second skin that goes over the cleaned (ouch!) wound. They breathe, are quite resistant to showering, and wounds heal in around 1 week. If it means anything, the Olympic Training Center uses this stuff. You never get a scab with this, so you can be out riding the same day, if you aren't too sore. It is important when using this treatment, to thoroughly clean the wound, and put the bandage on right away. It can be obtained at most pharmacies. Another possible source is Spenco second skin, which is sometimes carried by running stores and outdoor/cycling/ stores. If this doesn't help, you might try a surgical supply or medical supply place. They aren't as oriented toward retail, but may carry larger sizes than is commonly available. Also, you might check with a doctor, or university athletic department people. --------------------------------------------------------------------------- Knee problems (Roger Marquis marquis@well.sf.ca.us) As the weather becomes more conducive to riding and the racing season gets going and average weekly training distances start to climb a few of us will have some trouble with our knees. Usually knee problem are caused by one of four things: 1) Riding too hard, too soon. Don't get impatient. It's going to be a long season and there's plenty of time to get in the proper progression of efforts. Successful cycling is a matter of listening to your body. When you see riders burning out, hurting themselves and just not progressing past a certain point you can be fairly certain that it is because they are not paying enough attention to what their body is telling them. 2) Too many miles. Your body is not a machine. It cannot be expected to take whatever miles you feel compelled to ride without time to grow and adapt. If you keep this in mind whenever you feel like increasing your average weekly mileage by more than forty miles over two or three weeks you should have no problems. 3) Low, low rpms (also excess crank length). Save those big ring climbs and big gear sprints for later in the season. This is the time of year to develop fast twitch muscle fibers. That means spin, spin, spin. You don't have to spin all the time but the effort put into small gear sprints and high rpm climbing now will pay off later in the season. 4) Improper position on the bike. Unfortunately most bicycle salespeople in this country have no idea how to properly set saddle height. The most common error being to set it too low. This is very conducive to developing knee problems because of the excessive bend at the knee when the pedal is at, and just past, top dead center. Make sure your seat and cleats are adjusted properly by following the adjustment procedures found elsewhere. If after all this you're still having knee problems: 1) Check for leg length differences both below and above the knee. If the difference is between 2 and 8 millimeters you can correct it by putting spacers under one cleat. If one leg is shorter by more than a centimeter or so you might experiment with a shorter crank arm on the short leg side. 2) Use shorter cranks. For some riders this helps keep pedal speed up and knee stress down. I'm 6 ft. 1/2 in. and I ride 170mm cranks for most of the season. 3) Try the Fit-Kit R.A.D. cleat alignment device and/or a rotating type cleat/pedal like the Time pedal. 4) Cut way back on mileage and intensity (This is a last resort for obvious reasons). Sometimes a prolonged rest is the only way to regain full functionality and is usually required only if you try to "train through" any pain.