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- Path: sparky!uunet!portal!cup.portal.com!Ray_L_Curry
- From: Ray_L_Curry@cup.portal.com
- Newsgroups: rec.motorcycles
- Subject: Re: single vs. dual disk
- Message-ID: <74131@cup.portal.com>
- Date: Thu, 21 Jan 93 23:12:13 PST
- Organization: The Portal System (TM)
- Distribution: usa
- References: <C148x8.IMw@javelin.sim.es.com>
- <1993Jan21.044323.2907@pages.com>
- Lines: 29
-
- >BTW, would a single disk with two sets of two-pot calipers stop as well as
- >conventional dual disks with one set per disk? Phyzziks, please.
-
- Basic phyzziks, (aren't phyzziks those pills you used to able to buy to
- drop in water and make it bubble?), vehicle at speed equals kinetic
- energy, brakes convert that energy to heat. All things being equal, that's
- all it takes. There are almost an infinite number of variables that crop
- up. Stainless steel doesn't handle heat as well as cast iron but doesn't
- rust. Japanese bikes with stainless rotors benefit from duals because it
- distributes heat over a wider surface. Its also easier to fit a master
- cylinder that feels comfortable to the hand to modulate. The brake pad
- materials, rotor materials, air flow, these all impact the design of the
- system. Like the manufacturer that sent the letter to Motorcyclist saying
- their test of Kevin Swantz's GP bike versus a Honda, was unfair to them,
- the maker of the carbon fiber disk. The magazine had mentioned that the
- Suzuki's brakes were very weak in comparison to the Honda. Seems as though
- Kevin's bike has a bigger rotor is bigger and it is unshrouded because he
- uses them harder. The carbons disks and pads only work over a narrow
- temperature range and Kevin is the only rider in the world that gets his
- brakes hot enough to work with those particular rotors. The letter explained
- that if the magazine had used their rotors as specificed on one of the other
- rider's machines, they would have worked much better.
- All this aside, generally speaking, todays big bikes work better with
- duals. The new Yamaha RAAD bike will use a single because where would a
- second one go. The designers are going to make the brakes work under
- whatever constraints the bike is going to through at them. If one solution
- is easier and fits, why not use it? That alone will probably make it work
- a little better. Then again, the differences probably only show up on the
- track.
-