Originally Posted by
BigJeff
Measure the rake and trail on the two bikes.
Rake is the angle of the fork steerer tube/axle and
trail the distance between the projected line from the steerer tube/axle to ground measured backward to the perpendicular axle to ground.
In general, more rake decreases responsiveness and requires more input to turn, and less rake makes a bike "responsive... but twitchy"
While increasing trail makes the bike more likely to go in a straight line.
Many road bikes have very steep steerer tubes and very little rake, e.g. "straight forks", compared to C&V bikes which had bent forks for extra trail.
Most likely you Defy has far less rake and trail... very sporty, but not a very "hands free" bike... since it is compact, go 50x12 and speed up. As you increase speed it will make your trail more effective so you can be hands free.
Think of it as the "bad shopping cart wheel" it may wobble like hell unless you are pushing the cart fast.
The Roubaix is designed with more rake/trail (I believe)... I wouldn't compare the Defy to it.
Sorry, but there is a whole lot of wrong in this post.
First, rake is the hub's offset from the steering axis. The angle of the fork's steerer tube has nothing to do with it. ( the angle of the fork blades to the steerer tube affects rake, but it is not the definition of it, and the angle of steerer tube itself has no effect on rake).
Second, more rake doesn't decrease responsiveness. More rake equals less trail, and all else equal make the bike more responsive.
Third, whether a fork is curved or straight does not determine the amount of rake, i.e. offset. A straight fork can have a lot of rake, depending on how the fork blades are angled to the head tube.
Fourth, given that more rake equals less trail, a bike with less rake is not going to also have less trail.
http://calfeedesign.com/tech-papers/...bike-handling/
http://davesbikeblog.squarespace.com...f-history.html
I think your basic point that the geometry of the schwinn leads to a more stable ride is likely correct, but your explanation of rake and trail is way off.