performance road bike - trail

Callistus Valerius said:

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.

Quoted message said:

Quoted message said:

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.

Quoted message said:

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

Quoted message said:

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.

Callistus Valerius said:

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.

Quoted message said:

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

"Matt O'Toole" <[email hidden]> wrote

Quoted message said:

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

Quoted message said:

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.

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

From: [email hidden]

Quoted message said:

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

Quoted message said:

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.

What's the geometry or which bike is your touring bike?