Hi all
I have a Gary fisher rig 29er which is currently running rigid forks. The front end is very low, which added to the frame being too small anyway, is doing my head in.
I am considering some new forks as a means of raising the front end, looking at some 120mm manitou towers I’ve found in local classified. I don’t care about frame warranty issues, but wondering how much of an impact it will have on the handling? It would put about 50mm on the a-c length. I think the frame was designed for 100mm forks
Thoughts welcome
Cheers

2 wrongs don’t make a right, sounds like you should cut your losses and get a frame that fits and start from there.

Fair point, mattjg. I was thinking the forks could also transplant onto a bigger frame in future. I thought it would be interesting to try them on this frame, unless someone tells me it is a stupid plan (which I think you just did!)

Pop the current geometry in this calc…
http://bikegeo.muha.cc
…and see what effect it has. From a quick go, looks like an extra 50mm on the axle to crown would slacken the head & seat angle by about 2.5deg

Great link, thanks. I’ll have a fiddle about with the calculator

no I didn’t mean stupid plan, bikes are bikes and try whatever might work

but changing fork isn’t going to fix the problem of the frame being too small, likely it will exacerbate it as slackening the front will reduce ETT.

20mm on fork = 1 degree less of HA is a reasonable rule of thumb. longer forks raise the BB a bit too.

but if you like the forks and you’d keep them regardless (I ride a 120mm 29er HT, it works for me) then what’s to lose putting them on your existing frame for a try.

with 50mm on A/C you’ll notice more tyre in front of you, your weight back a bit and the steering less twitchy. Short stem/wide bars work well with slacker bikes in my experience.

Thanks mattjg, good advice. What frame do you have your 120mm forks on?

Canfield Yelli Screamy, great fun trailsy/all-round frame.