Twin gearbox troubles

timetraveller

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There is but it takes a very brave person to do it. You can cut off the original and weld in a piece of aluminium the shape of the later crankcase bosses. I have had it done to at least two crankcases which had the original boss broken off and the later design is much stronger than the original. It is often forgotten that the engines were being developed throughout the whole production run. Although financial trouble caused troubles with some aspects of quality to-wards the end the 'D's were developed after consultation with many riders and there are several aspects of the later engine and suspension which are better than the early ones. Note that I have no axe to grind here as I have 'B', 'C' and 'D' engines. I seem to remember that his 'ighness the 'iggins gave an improved design for the pivot in MPH some time ago :).
 

bmetcalf

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Some people have added a gusset in the fore and aft direction. Distortion may be a problem, so don't do it unless others agree.
 

Upstreeter

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And the winner of the gearbox problem diagnosis prize is....wait for it.... Len Matthews!. Thanks Len, and a big sigh of relief all round with no crankcases to split. The main shaft selector fork is totally b..g...d and has filled its corresponding channel between the dogs with brass. The curious thing is that there are no signs of wear and there was plenty of oil in the gearbox - no blueing of teeth, nothing. This has wiped the smile off my face.
 

John Appleton

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The main shaft selector fork is totally b..g...d and has filled its corresponding channel between the dogs with brass.
Hi Upstreeter, my Rapide used to do this on a regular basis! Found the cause to be excess end float in the clutch mainshaft, which I rectified by fitting a 40 thou. spacer ,in addition to E76, behind the bearing in the gearbox manhole cover. You should also check that the G30 spindle is not bent as a result of the siezure.It is also worth mentioning that ,since renewing the gearbox bearings in a recent rebuild, the extra spacer is no longer necessary although there is no obvious wear in the original bearings
John
 
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Upstreeter

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Thanks John...very helpful and from, imo one of England's most beautiful counties....where I bought my Shadow in the first place.:)
 

rapcom

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Timewarp?

I doubt if any of this club will bring the 21st century to Suffolk. Most of us struggle with the 20th !
 
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