4 speed g/box

[Chris KC]

Ah so you were the owner that suffered this problem, I'd heard of the failure in Switzerland but forgotten who it was.. The other owner was the late Peter Fearn going to Woolaton Park many years ago. It doesn't seem to happen to 2 SYN boxes. I also suspect that incorrect setting of the selector bars had something to do with the cause.

That's right Dave, I (or at least a more youthful version of me) wrote it up in grey mag 1997D. I agree, it only affects boxes with synchro on 2nd gear. I dare say selector adjustment is part of the story (in fact I remember Hescho, the Bosnian mechanic who helped me, put a spot of weld on the interlock plate to restrict how far the lever could go); however it was excessive end play (there was quite a lot) which allowed the ring to slide that far, with scant objection from the weak detent balls. I might be wrong but I don't think this failure could occur if end float is within sensible limits. I subsequently rebuilt the box with new bearings and carefully shimmed them, and have covered many miles since without trouble.

Incidentally I recently replaced the synchro with a 4 speed crash box I picked up in a local auction for under a tenner. I was dazzled by the general condition of the crash box inside; and it looks much more robust than the synchro. I'm also keen to try out the slightly lower ratios which Reckless mentioned above. You wouldn't choose them for racing but under certain circumstances they could be quite handy.