Subject: Re: Re: fork rake Posted by: john olsen on June 05, 1998 at 15:37:51: In Reply to: Re: fork rake posted by Jim Kish on December 29, 1997 at 09:05:55:

Message: : : What happens if I change my fork from 43mm rake to 45mm : : ? The frame is 54cm cannondale, 73 deg. head tube, : : (stock fork is 43mm rake). How will this affect handling? : The interplay between fork rake, head angle and wheel size determines trail. Trail is the distance that the contact patch of the tire "trails" behind the steering axis. Trail is what gives the bike its steering stability, the more trail you have, the more the bike tends to return to the "straight ahead" position. : To make a long answer short, the trail using your 43mm rake fork is 57.76mm, assuming 700C wheels with a 25mm tire profile. With the 45mm fork, trail is reduced to 55.67mm. Not a big difference. One last thing, unless your new fork height is identical to the old one, your head angle will steepen or slacken a bit, changing the trail again.