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TRACK SET-UP

At Spectrum Cycles we design and build custom frames because it's the best way to set a rider up on a bicycle properly. This holds true for tandems, racing bikes, touring machines and especially track bikes. That said, here are some tips on how to set up your track bicycle.

Setting up a track position is similar to setting up a road position except that the pelvis is generally a bit forward compared to the road position (not a lot, just a bit...like one cm. for a 5'7" rider) Saddle height (or leg extension at 6:00 O'clock) usually is a tiny bit lower as cranks tend to be shorter and typical crank RPMs are much higher. The drops of the bars should be a bit lower relative to saddle height (again not more than a cm. or so unless we are dealing with a tall sprinter). Reach (horizontal distance from saddle to hands in drops) is usually about the same as road reach. Note that I am talking about setup, not necessarily riding position. I mention this because in competition, a track rider's pelvis position reference points vary much more than the typical road rider's position does. Next time you watch a good race at your local velodrome, notice that at moderate speeds, most riders sit in the saddle in the "sweet spot" while at other times, during a hard chase or in a sprint, they "ride the rivet", sometimes for quite a few laps. Check out your videos of the track world’s pursuit competition if you want to see what "riding the rivet" means.

When setting up the bike for the track, consider the top-tube and stem lengths together as it is the relationship between and the sum of the two that affects handling. The relationship between top tube length and stem length will affect the road rider and track rider's center of gravity in the same way. However, because track bikes average much steeper head angles and shorter fork rakes than road bikes do, much more careful accommodation of this front center difference must be attended to during frame design. Generally, this comes down to a subtle shift in the typical top tube/stem length relationships. Compared to a well-designed road bike, track bikes should have a slightly higher top tube/stem ratio. Usually that means that your track bike should have essentially the same top tube length as your road bike, but it will have a slightly shorter stem. This does not apply to smaller track bikes as an already short stem will tend to have more of a "steering wheel" effect and should be avoided if possible. For those smaller frames, the top tube and stem length come down together.

Seat tube length is another major consideration when setting up the track bike. The rule of thumb was always that your track frame should have a 1-2cm shorter seat tube than your road frame has. This rule works fairly well assuming your road frame fits you well. (Remember what I said in the position paragraph above.) The saddle to bar drop should be 1-2cm. lower than your road bike. If your road frame fits you pretty well, your 17 degree stem can go down a couple centimeters or your 0 rise stem is pretty much burred. Either way, increasing your saddle to bar drop by 1-2 cm. will usually require a shorter seat tube. Also, remember that your leg to saddle extension is a few mm. shorter which brings everything down a bit more anyway.

Seat angle... Quite simple. Because we want to bring the pelvis forward a cm. or so, we bring the seat tube forward by about that amount. Depending on the bb to saddle distance, that can mean anywhere from half a degree to almost three degrees. Of course the rider's style and events effect all this stuff. These do work for the averages though.

Chain stay length... Almost always, the chain stay length is as short as you can get it and retain tire/seat tube clearance. This usually works out to 15.125"-15.625" measured from the bb center to the center of the rear axle in its most forward position. The reasons to have the chain stay as short as possible are; the desire to keep handling, power transmission and jump as quick as possible, to assure that once the chain tension is adjusted correctly, the wheel stays as far forward as possible. In some cases, especially with larger track frames, we will actually crimp the back of the seat tube to enable us to shorten the rear end even further. Of course that would not be a good idea on a smaller frame.

Next question; type of track's effect on frame design:
First thing to realize that even though different tracks have very different characteristics, there is much less variability between tracks than the variability you will encounter on a twenty mile road ride (unless you live in Kansas). Therefore, track frames can be "tuned" more precisely to specific tracks, events, rider experience, speeds expected and rider style. For example a Six-Day frame will be quite different from a sprint frame while a Crit. frame is not really very deferent from your typical road-racing frame. Road frames need to be able to work at least reasonably well no matter what they encounter. Track frames really work best if they are tailored as much as possible to the expected conditions.

Crimps... It is pretty rare that we can get away without using crimps on our chain stays. Most track riders do train on fairly wide tires (cheaper and longer lasting) and they do take up more room. Keep in mind that chain stays are the most "dimensionally challenged" tubes in the frame. The builder has to be sure that he can fit the right chain stay between both the tire and the largest expected chain ring (sometimes as big as a 53). We do try to keep the crimps as small as possible to retain as much torsional rigidity as we can. We do not oval the chain stays as that is ALWAYS less efficient from a mechanical perspective. On road bikes it is less critical, but on the track, every little bit helps.

Chain stay bridges... We always use them. Chain stay bridges do two things. First, they effectively shorten the chain stay length from a mechanical perspective, stiffening up the bottom bracket and rear end somewhat. Second, and more importantly, they dissipate the stresses on the chain stays where they enter the bb. It is exceptionally rare that we see chain stays that have cracked near the bb when there is a bridge while we see chain stays cracked just behind the bb all the time that have no bridge. The trick here is that a chain stay bridge has a larger radius stress riser than most bb shell lugs and they are also more compliant. The only good reason to leave out a chain stay bridge is to save a few bucks.

Remember, if you have a question about a track frame contact us. That’s why we are here!