I thought It was clutch slip, but I think it actually may be a gearbox, (1st gear) issue?

mdt-son said:

I know this reply is too late, as you have assembled your transmission. Your selector shaft is (was) unsuppoted at one end. Wiggling it may produce the desired effect.


Again, a late comment. Great renovation, but you probably know gears should be replaced in pairs because of the wear pattern.

- Knut

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Hi Knut:

You may be right regarding the selector shaft being part of my problem. It did show some wear and corrosion/rust, so I replaced it. Once I finished with testing and I put everything back together for real, the problem disappeared!

Thank you for your advice regarding gear replacement. It did occur to me, but the main shaft first and second gears were in pretty decent shape, even the bronze bushings were still good. That and they seemed to mesh pretty nicely with the new layshaft first and second gears. The gearbox now shifts smoothly and appears to be pretty quiet, (i.e. no disconcerting noises). I guess time will tell if I made the right call.

Cheers,

James

mdt-son said:

Again, a late comment. Great renovation, but you probably know gears should be replaced in pairs because of the wear pattern.

- Knut

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I overhauled my gearbox earlier this year, and was aware that gears should be replaced in pairs, but that would have taken the parts cost over £500, which was more than I wanted to spend, so I rethought the usual advice ...

If gear A is half the size of gear B, then the teeth on gear B get half the wear than the ones on gear A. If only gear A is worn, then why replace the half-worn gear B?

MichaelD said:

If gear A is half the size of gear B, then the teeth on gear B get half the wear than the ones on gear A. If only gear A is worn, then why replace the half-worn gear B?

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Your thinking is wrong. Torque of gear B is half the torque of gear A, but - and this is essential - opposite contact forces acting on the meshing gear teeth are of the same magnitude, so gear A and B will have the same rate of wear.

Your decision not to replace gear(s) "B" was biased by your erroneous logic, and now you risk damaging the new gear(s) "A" as well. Trying to be smarter than the experts backfires at you!

- Knut