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Allan G
Total Likes: 1
Original Post (Thread Starter)
#823331 09/11/2020 12:35 PM
by Phil in Germany
Phil in Germany
Dear all,

I do have an issue with my 71 Firebird Scrambler.

When shifting up from 1st to 2nd and 2nd to 3rd the shifting is not like it's supposed to be. If the shifting takes place at anything above 2.5k rpm the shifting is noisy/crunchy not as slick as I am used to on my Lightning. I have the impression that the lever even vibrates slighly.

I am inclined to say, it is not clutch related as 1st and 4th shifting is fine. The clutch frees completely, no drag, I can easily shift from 1st to neutral when standing at a red light.

I've had the gearbox out once but did not see anything wrong. Layshaft end float is fine, the forks are not dis-coloured, the cam plate shows some sign of use but I had not been worried and put everything back in. The bearings in the end cover seemed to be okay as well

Unfortunately, the issue persists. eek

Before I just swap the gearbox with another one which could be assembled from parts in the shop, this time with a new camplate, do you have any ideas where to watch out for? What could be the reason for that poor behaviour?

This cam plate from my parts stash does not look too promising from my perspective and I am also not sure whether it is interchangeable with the 71-cam plate.

[Linked Image from]

[Linked Image from]

I am looking forward to your highly appreciated input/hints/tips .


Liked Replies
#826148 Oct 10th a 07:59 PM
by Phil in Germany
Phil in Germany
Hi there,

today I took the bike for a test ride after having completed the re-assembly.

The shifting issues have disappeared. The bike shifts easily up without a difference no matter revs being high or low.

Phew, I think the slightly bent layshaft was the issue.

Many thanks for your support, mates. Without your hints to check this I would still be scratching my head.


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