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.] --------------------------------------------------------------------------- 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. =========================================================================== Nutrition and Food 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) =========================================================================== Frames Frame Stiffness (Bob Bundy bobb@ico.isc.com) As many of you rec.bicycles readers are aware, there have been occasional, sometimes acrimonious, discussions about how some frames are so much stiffer than others. Cannondale frames seem to take most of the abuse. The litany of complaints about some bike frames is long and includes excessive wheel hop, numb hands, unpleasant ride, broken spokes, pitted headsets, etc. I was complaining to a friend of mine about how there was so much ranting and raving but so little empirical data - to which he replied, "Why don't you stop complaining and do the measurements yourself?". To that, I emitted the fateful words, "Why not, after all, how hard can it be?". Following some consultation with Jobst and a few other friends, I ran the following tests: The following data were collected by measuring the vertical deflection at the seat (ST), bottom bracket (BB) and head tube (HT) as a result of applying 80lb of vertical force. The relative contributions of the tires, wheels, fork, and frame (the diamond portion) were measured using a set of jigs and a dial indicator which was read to the nearest .001 inch. For some of the measures, I applied pressures from 20 to 270 lbs to check for any significant nonlinearity. None was observed. The same set of tires (Continentals) and wheels were used for all measurements. Note that these were measures of in-plane stiffness, which should be related to ride comfort, and not tortional stiffness which is something else entirely. Bikes: TA - 1987 Trek Aluminum 1200, this model has a Vitus front fork, most reviews describe this as being an exceptionally smooth riding bike SS - 1988 Specialized Sirus, steel CrMo frame, described by one review as being stiff, hard riding and responsive DR - 1987 DeRosa, SP/SL tubing, classic Italian road bike RM - 1988 Cannondale aluminum frame with a CrMo fork, some reviewers could not tolerate the rough ride of this bike TA SS DR RM ---------- ---------- ---------- ---------- ST BB HT ST BB HT ST BB HS ST BB HT diamond 1 1 0 2 2 0 2 2 0 1 1 0 fork 3 11 45 3 9 36 4 13 55 3 10 40 wheels 2 2 2 2 2 2 2 2 2 2 2 2 tires 68 52 66 68 52 66 68 52 66 68 52 66 total 74 66 113 75 65 104 76 69 123 74 65 108 What is going on here? I read the bike mags and this net enough to know that people have strong impressions about the things that affect ride comfort. For example, it is common to hear people talk about rim types (aero vs. non-aero), spoke size, butting and spoke patterns and how they affect ride. Yet the data presented here indicate, just a Jobst predicted, that any variation in these factors will essentially be undetectable to the rider. Similarly, one hears the same kind of talk about frames, namely, that frame material X gives a better ride than frame material Y, that butted tubing gives a better ride that non-butted, etc. (I may have even made such statements myself at some time.) Yet, again, the data suggest that these differences are small and, perhaps, even undetectable. I offer two explanations for this variation between the data and subjective reports of ride quality. Engineering: These data are all static measurements and perhaps only applicable at the end of the frequency spectrum. Factors such as frequency response, and damping might be significant factors in rider comfort. Psychology: There is no doubt that these bikes all look very different, especially the Cannondale. They even sound different while riding over rough roads. These factors, along with the impressions of friends and reviews in bike magazines may lead us to perceive differences where they, in fact, do not exist. Being a psychologist, I am naturally inclined toward the psychological explanation. I just can't see how the diamond part of the frame contributes in any significant way to the comfort of a bike. The damping of the frame should be irrelevant since it doesn't flex enough that there is any motion to actually dampen. That the frame would become flexible at some important range of the frequency spectrum doesn't seem likely either. On the other hand, there is plenty of evidence that people are often very poor judges of their physical environment. They often see relationships where they don't exist and mis-attribute other relationships. For example, peoples' judgement of ride quality in automobiles is more related to the sounds inside the automobile than the ride itself. The only way to get a good correlation between accelerometers attached to the car seat and the rider's estimates of ride quality is to blindfold and deafen the rider (not permanently!). This is only one of many examples of mis- attribution. The role of expectation is even more powerful. (Some even claim that whole areas of medicine are built around it - but that is another story entirely.) People hear that Cannondales are stiff and, let's face it, they certainly *look* stiff. Add to that the fact that Cannondales sound different while going over rough roads and perhaps the rider has an auditory confirmation of what is already believed to be true. Unless anyone can come up with a better explanation, I will remain convinced that differences in ride quality among frames are more a matter of perception than of actual physical differences. --------------------------------------------------------------------------- Frame materials [Ed note: I got this information from some of the books I have. People in the know are welcome to update this.] There are several materials that are used to make bicycle frames. They are: Mild steel - usually used in cheap department store bikes. Frames made from mild steel are heavy. High carbon steel - a higher quality material used in low end bikes. Reynolds 500 is an example. Steel alloy - lighter and better riding than high-carbon frames. Reynolds 501 and Tange Mangaloy are examples. Chro-moly - also called chrome-molybdenum or manganese-molybdenum steel. One of the finest alloys for bike frames. Reynolds 531 and Columbus SL and SP are some of the best known brands. Carbon fiber - high tech stuff. Made from space-age materials, frames made of this are very light and strong. Some problems have been seen in the connections between the tubes and bottom bracket, etc. Aluminum - Light frames, usually with larger diameter tubes. Cannondale is a well-known brand. --------------------------------------------------------------------------- Bike pulls to one side (Jobst Brandt jobst_brandt@hplabs.hp.com) For less than million dollar bikes this is easy to fix, whether it corrects the cause or not. If a bike veers to one side when ridden no-hands, it can be corrected by bending the forks to the same side as you must lean to ride straight. This is done by bending the fork blades one at a time, about 3 mm. If more correction is needed, repeat the exercise. The problem is usually in the forks although it is possible for frame misalignment to cause this effect. The kind of frame alignment error that causes this is a head and seat tube not in the same plane. This is not easily measured other than by sighting or on a plane table. The trouble with forks is that they are more difficult to measure even though shops will not admit it. It takes good fixturing to align a fork because a short fork blade can escape detection by most measurement methods. Meanwhile lateral and in-line corrections may seem to produce a straight fork that still pulls to one side. However, the crude guy who uses the method I outlined above will make the bike ride straight without measurement. The only problem with this is that the bike may pull to one side when braking because the fork really isn't straight but is compensated for lateral balance. This problem has mystified more bike shops because they did not recognize the problem. Sequentially brazing or welding fork blades often causes unequal length blades and bike shops usually don't question this dimension. However, in your case I assume the bike once rode straight so something is crooked --------------------------------------------------------------------------- Frame repair (David Keppel pardo@cs.washington.edu) (Disclaimer: my opinions do creep in from time to time!) When frames fail due to manufacturing defects they are usually replaced under warranty. When they fail due to accident or abuse (gee, I don't know *why* it broke when I rode off that last motorcycle jump, it's never broken when I rode it off it before!) you are left with a crippled or unridable bike. There are various kinds of frame damage that can be repaired. The major issues are (a) figuring out whether it's repairable (b) who can do it and (c) whether it's worth doing (sometimes repairs just aren't worth it). Kinds of repairs: Bent or cracked frame tubes, failed joints, bent or missing braze-on brackets, bent derailleur hangars, bent or broken brake mounts, bent forks, etc. A frame can also be bent out of alignment without any visible damage; try sighting from the back wheel to the front, and if the front wheel hits the ground to one side of the back wheel's plane (when the front wheel is pointing straight ahead), then the frame is probably out of alignment. * Can it be repaired? Just about any damage to a steel frame can be repaired. Almost any damage to an aluminum or carbon fiber frame is impossible to repair. Titanium frames can be repaired but only by the gods. Some frames are composites of steel and other materials (e.g., the Raleigh Technium). Sometimes damage to steel parts cannot be repaired because repairs would affect the non-steel parts. Owners of non-steel frames can take heart: non-steel frames can resist some kinds of damage more effectively than steel frames, and may thus be less likely to be damaged. Some frames come with e.g., replacable derailleur hangers (whether you can *get* a replacement is a different issue, though). Also, many non-steel frames have steel forks and any part of a steel fork can be repaired. Note: For metal frames, minor dents away from joints can generally be ignored. Deep gouges, nicks, and cuts in any frame may lead to eventual failure. With steel, the failure is generally gradual. With aluminum the failure is sometimes sudden. Summary: if it is steel, yes it can be repaired. If it isn't steel, no, it can't be repaired. * Who can do it? Bent derailleur hangers can be straightened. Indexed shifting systems are far more sensitive to alignment than non-indexed. Clamp an adjustable wrench over the bent hanger and yield the hanger gently. Leave the wheel bolted in place so that the derailleur hanger is bent and not the back of the dropout. Go slowly and try not to overshoot. The goal is to have the face of the hanger in-plane with the bike's plane of symmetry. Just about any other repair requires the help of a shop that builds frames since few other shops invest in frame tools. If you can find a shop that's been around for a while, though, they may also have some frame tools. * Is it worth it? The price of the repair should be balanced with * The value of the bicycle * What happens if you don't do anything about the damage * What would a new bike cost * What would a new frame cost * What would a used bike cost * What would a used frame cost * What is the personal attachment If you are sentimentally attached to a frame, then almost any repair is worth it. If you are not particularly attached to the frame, then you should evaluate the condition of the components on the rest of the bicycle. It may be cheaper to purchase a new or used frame or even purchase a whole used bike and select the best components from each. For example, my most recent reconstruction looked like: * Bike's estimated value: $300 * Do nothing about damage: unridable * Cost of new bike: $400 * Cost of new frame: $250+ * Cost of used bike: $200+ * Cost of used frame: N/A * Cost of repair: $100+ * Personal attachment: zip Getting the bike on the road again was not a big deal: I have lots of other bikes, but I *wanted* to have a commuter bike. Since I didn't *need* it, though, I could afford to wait a long time for repairs. The cost of a new bike was more than I cared to spend. It is hard to get a replacement frame for a low-cost bicycle. I did a good bit of shopping around and the lowest-cost new frame that I could find was $250, save a low-quality frame in the bargain basement that I didn't want. Used frames were basically the same story: people generally only sell frames when they are high-quality frames. Because the bike was a road bike, I could have purchased a used bike fairly cheaply; had the bike been a fat-tire bike, it would have been difficult to find a replacement. The cost of the frame repair included only a quick ``rattlecan'' spray, so the result was aesthetically unappealing and also more fragile. For a commuter bike, though, aesthetics are secondary, so I went with repair. There is also a risk that the `fixed' frame will be damaged. I had a frame crack when it was straightened. I could have had the tube replaced, but at much greater expense. The shop had made a point that the frame was damaged enough that it might crack during repair and charged me 1/2. I was able to have the crack repaired and I still ride the bike, but could have been left both out the money and without a ridable frame. * Summary Damaged steel frames can always be repaired, but if the damage is severe, be sure to check your other options. If the bicycle isn't steel, then it probably can't be repaired. --------------------------------------------------------------------------- Frame Fatigue (John Unger junger@rsg1.er.usgs.gov) I think that some of the confusion (and heat...) on this subject arises because people misunderstand the term fatigue and equate it with some sort of "work hardening" phenomena. By definition, metal fatigue and subsequent fatique failure are well-studied phenomena that occur when metal (steel, aluminum, etc.) is subjected to repeated stresses within the _elastic_ range of its deformation. Elastic deformation is defined as deformation that results in no permanent change in shape after the stess is removed. Example: your forks "flexing" as the bike rolls over a cobblestone street. (an aside... The big difference between steel and aluminum as a material for bicycles or anything similar is that you can design the tubes in a steel frame so that they will NEVER fail in fatigue. On the other hand, no matter how over-designed an aluminum frame is, it always has some threshold in fatigue cycles beyond which it will fail.) This constant flexing of a steel frame that occurs within the elastic range of deformation must not be confused with the permanent deformation that happens when the steel is stressed beyond its elastic limit, (e. g., a bent fork). Repeated permanent deformation to steel or to any other metal changes its strength characteristics markedly (try the old "bend a paper clip back and forth until it breaks" trick). Because non-destructive bicycle riding almost always limits the stresses on a frame to the elastic range of deformation, you don't have to worry about a steel frame "wearing out" over time. I'm sorry if all of this is old stuff to the majority of this newsgroup's readers; I just joined a few months ago. I can understand why Jobst might be weary about discussing this subject; I can remember talking about it on rides with him 20 years ago.... =========================================================================== Injuries 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. ---