performance road bike - trail

Callistus Valerius

What performance road bike has the most trail. They seem to range from
5.7cm to 5.00 cm (trek 1000 - trek 5200). Since trail determines how stable
a bike will be, I was thinking about a performance road bike with about 6.2
cm trail for a frame that would fit someone 6 feet tall ( a 58 frame on a
Trek).

Matt O'Toole

Callistus Valerius wrote:

> What performance road bike has the most trail. They seem to range
> from
> 5.7cm to 5.00 cm (trek 1000 - trek 5200). Since trail determines how
> stable a bike will be, I was thinking about a performance road bike
> with about 6.2 cm trail for a frame that would fit someone 6 feet
> tall ( a 58 frame on a Trek).

Head angle has an effect on stability too, so you can't look at trail alone.
It's the combination of the two that matters, and there's no magic number.
Generally, larger road frame sizes have steeper head angles, and more trail to
compensate.

Matt O.

Callistus Valerius

> > What performance road bike has the most trail. They seem to range
> > from
> > 5.7cm to 5.00 cm (trek 1000 - trek 5200). Since trail determines how
> > stable a bike will be, I was thinking about a performance road bike
> > with about 6.2 cm trail for a frame that would fit someone 6 feet
> > tall ( a 58 frame on a Trek).
>
> Head angle has an effect on stability too, so you can't look at trail
alone.
> It's the combination of the two that matters, and there's no magic number.
> Generally, larger road frame sizes have steeper head angles, and more
trail to
> compensate.
>
> Matt O.
>

The little guys get super stable bikes with lots to trail, and the big
guys are stuck with little trail and unstable bikes. I guess that comes
with mass production, since the target is smaller guys.

Matt O'Toole

Callistus Valerius wrote:

> The little guys get super stable bikes with lots to trail, and
> the big guys are stuck with little trail and unstable bikes. I guess
> that comes with mass production, since the target is smaller guys.

That really has nothing to do with it. Small frames have slack head angles for
better toe clearance, and also to make up for a shorter wheelbase. Big frames
have steep head angles to make the wheelbase shorter.

I do agree that larger frames tend to be overly quick steering, because of an
obsession with short wheelbases and steep head angles. But the solution is not
just to find a bike with more trail. Merely adding trail to a steep bike might
make it more stable at high speeds, but create other handling problems.

Look for a bike with a longer wheelbase and a slacker head angle, matching
trail, and an overall milder design -- like the 70s-style bikes that seem to be
making a comeback -- usually called "club sport" or "road sport" geometry.
Though they're out of the mainstream these days, there are plenty of stable,
sweet handling bikes around. Just find one of those and buy it, instead of
screwing around with geometry yourself. Cross bikes are another good choice.
Tim McNamara, who posts here, told how he beat all his friends to the bottoms of
mountain passes in the Alps, because his Gunnar Crosshairs handled so much
better than their bikes. I borrowed a Bianchi Reparto Course cross bike once,
and I can't imagine a sweeter all around handler.

I'm a fan of bikes like this too. That said, I ride a short, steep,
quick/wobbly Italian job.

Matt O.

Mike Jacoubowsky/Chain Reaction Bicycles

> The little guys get super stable bikes with lots to trail, and the big
> guys are stuck with little trail and unstable bikes. I guess that comes
> with mass production, since the target is smaller guys.

Actually, no. Wheelbase is a major contributor to stability, and the larger
bikes have longer wheelbases than smaller ones. Stability with most modern
larger-framed road bikes is almost a given, providing that materials &
design make for a rigid-enough platform.

Ideally, you want a bike that doesn't handle like a boat at moderate speeds,
and remains stable at higher speeds. I doubt many currently-made road bikes
are too far off the mark in that regard, given that geometry isn't exactly
rocket science, and we're many many years into the future from such twitchy
designs as the older Gios Torino (what did that have, a 76 degree head
tube???!!!).

I think it's a tougher job on the smaller bikes to get a combination of
handling characteristics that works well.

--Mike--
Chain Reaction Bicycles
www.ChainReaction.com

Peter Cole

"Matt O'Toole" <matt@deltanet.com> wrote
>
> Look for a bike with a longer wheelbase and a slacker head angle, matching
> trail, and an overall milder design -- like the 70s-style bikes that seem to
be
> making a comeback -- usually called "club sport" or "road sport" geometry.
> Though they're out of the mainstream these days, there are plenty of stable,
> sweet handling bikes around. Just find one of those and buy it, instead of
> screwing around with geometry yourself. Cross bikes are another good
choice.

Touring frames have geometries similar to the older frames without the high
BB's of cross bikes. Long chainstays are a must for stable large frames.

Chris Zacho The Wheelman

Wouldn't too much stability be a BAD thing on a racing machine? You want
it to be nimble and have a quick response. Stability would resist this,
I would think.

- -

"May you have the wind at your back.
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner

Chris Zacho The Wheelman

From: peter_cole_no_spam_at_all@comcast.net
>Touring frames have geometries similar
>to the older frames without the high BB's
>of cross bikes. Long chainstays are a
>must for stable large frames.

Touring bikes are definitely stable. I know, I have one (and love it for
that). However, as a "performance" bike, it's TOO stable. Rides like on
rails, even at high speed carrying a full set of panniers and camping
equipment.

However, races rarely take place "on rails", if you know what I mean.
And BTW, the longer chainstays are mainly for heel clearance, not
stability.

- -

"May you have the wind at your back.
And a really low gear for the hills!"

Chris Zacho ~ "Your Friendly Neighborhood Wheelman"

Chris'Z Corner
http://www.geocities.com/czcorner