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Old 05-02-09 | 05:51 AM
  #35  
Picchio Special
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Joined: Jul 2007
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From: Lancaster County, PA

Bikes: '39 Hobbs, '58 Marastoni, '73 Italian custom, '75 Wizard, '76 Wilier, '78 Tom Kellogg, '79 Colnago Super, '79 Sachs, '81 Masi Prestige, '82 Cuevas, '83 Picchio Special, '84 Murray-Serotta, '85 Trek 170, '89 Bianchi, '90 Bill Holland, '94 Grandis

Originally Posted by Roll-Monroe-Co
OK, can someone explain to me about track bike geometry?

My understanding of trail and handling is that there is a tradeoff between high and low speeds:

Low trail=low speed stability (quick handling because you can make fast directional adjustments), less stability at high speed (because of quick reaction time)

Hi trail= low speed instability (wobbly handling at low speed), great high speed stability (rides like its on rails at speed)

So which do you want for a track bike? I always assumed that track bikes (which I've never ridden) would have high trail for stability at speed, speed being something you hopefully are spending a lot of time with on the track (which is consistent with very low fork rake that I've observed on track bikes)

However, maybe being nimble (low trail) is actually better for weaving in and out of your competitors. And somehow, despite the bike's being twitchy at speed, you don't lose control when you're hammering away.

Which is it?
On a track bike, you want lower trail for maneuverability. Stability at high speed isn't as much of an issue since you're generally not riding for hours at a time and the banking is doing the cornering for you. High trail bikes corner via lean and steer more from the hips; low trail bikes steer more from turning the bars and allow for quick change of direction. A bike for a 6-day race, like those ridden in the early 20th century, would regain some long-distance comfort via a slacker seat tube angle. A bike built for a longer track event will also gain some stability via a lower bottom bracket than a bike for a sprint event.
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