Has anybody ever had problems with the FB stock transmissions bending forks? I replaced transmissions in a customer car in May, took out whatever tranny was in it (had been installed sometime in '01, or so the case said), put in an ISC transmission. It ran two "full" SCCA weekends in May and July, and thenin the last race in the rain it gave out again, with the same symptoms.

The symptoms are that it will no longer go in 4-R, and it's done it both times. My only guess is it's the fork either bending or jamming, but regardless, it's not good. I'm wondering if anybody else has had the same problems and if there's an "easy" fix, legal or not. It's a '79 ITA car, originally built by Oka (and as far as I know maintained for a while), and was originally a Pro7 car in CA before it came here and has been slowly turned into a full ITA car.

TIA.

 

FB forks do wear out; where they rub the shift collar. The service manual has a spec for side clearance, check it with a feeler gauge between the fork and the coller. When the clearance gets too great, it is time for a new fork.

Forks cost $50 to $80, and most people are too cheap to replace them when they should.

Another failure mode is the hardware securing the shift forks and shift fingers to the shift rods or shafts.