I have an older MTB that I refurbished last year and made into a fully rigid bike. I want to get a new suspension fork this year. The original fork was a 80mm Judy TT. I am considering replacing it with a 100 mm Manituo Match. This will result in a 20mm increase in the axle-to-crown measurement. I know this will slacken the head tube angle and relax the steering, but will this make the bike unrideable and/or cause any damage to the frame? The bike is a 2003 Gary Fisher Wahoo. It has the older pre- G2 geometry.

Thanks.