less fork rake = faster turn-in?

[Tony Healy]

Hi, Know that some DH mt bikes have adjustable head tubes to steepen up the steering. [Same with
some motorcycles.] My old road bike had steeper angles so it was a quick turner. My newer road bike
is a bit slacker but fits me better. Have to work a little more to turn it in descents tho.

Can't change the head tube angle. Would switching to a fork with less rake make it drop into turns a
little quicker? If so, is there much of a difference in handling between a fork with 40mm rake and
45mm rake? (that seems to be the range for road forks)

Thanks for any thoughts!

Tony

 

[John Retchford]

Tony Healy wrote:
>
> Hi, Know that some DH mt bikes have adjustable head tubes to steepen up the steering. [Same with
> some motorcycles.] My old road bike had steeper angles so it was a quick turner. My newer road
> bike is a bit slacker but fits me better. Have to work a little more to turn it in descents tho.
>
> Can't change the head tube angle. Would switching to a fork with less rake make it drop into turns
> a little quicker? If so, is there much of a difference in handling between a fork with 40mm rake
> and 45mm rake? (that seems to be the range for road forks)
>
> Thanks for any thoughts!
>
A parameter that affects the quickness of steering is usually called trail and is the distance that
the tyre contact patch lies behind the point where the steerer axis meets the road. Reducing the
trail (more fork rake) reduces the directional stability (quicker steering), while more trail (less
fork rake) increases stability (slower steering). All this is for the same head angle. Steepening
the head angle requires a fork with less rake to maintain the same trail.

John Retchford