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Motorbike gearbox oopsie


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Crashed my bike 2 years ago. Took a year to do the cosmetic rebuild then found a bit of circlip in the oil. So took another year to do the engine finally producing this...

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Went up the road and the gearbox seemed a bit “funny”. So on a straight bit I went up through the gears, 1,2,4,3,5,6 oops. Just to make sure I tried another 50 times with no difference - bums!

So at the weekend it now looks like....

94733A43-7646-47DF-AFDA-917BF59809FA.jpeg.c066c5d55a8af25234c9c4b3b763c29b.jpeg
 

Dont know if 3/4 are transposed on the input and output shaft or whether the selector forks are wrong but,I’ll soon find out.

 

ps. I realise the photos are upside down but I’m too depressed to do anything about it.

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Think yourself lucky !  I replaced the crank on a CBX 1000 6 cylinder Honda and when putting the bottom half of the crankcase on I missed lining up one of the selector forks and only discovered this when getting ready to test ride the bike. Much grumbling and cleaning of jointing compound later all was well. ALWAYS spin the gearbox output shaft and test the gear selection before putting the motor back in the frame. As an aside, the camshafts on these Honda's are in two halves with a simple sleeve joint connecting them.

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I don’t count myself lucky, thank you very much! On the  bench, I checked all the right gears were there but not necessarily in the right order.

ps. I used to love the sound of a cbx with a noisy exhaust - never owned one though.

Edited by SpringDon
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2 hours ago, SpringDon said:

I don’t count myself lucky, thank you very much! On the  bench, I checked all the right gears were there but not necessarily in the right order.

ps. I used to love the sound of a cbx with a noisy exhaust - never owned one though.

A guy on a CBX used to ride between Dundee and Perth most weekends back in about 1978/79 and you heard him coming from miles away, it was incredible!

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Quite a sound. The problem was that they really did guzzle oil and you had to check it very regularly or the result was a leg out of bed and a lot of ali welding and metal spraying to get them up and running again. The last model,the Pro-link suspension type even handled reasonably !

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In an effort to maintain my flagging motivation, I will add photos to document my descent into despair.

Side casing removed and just about to take off clutch...

522E56E7-9544-4862-8397-C4AE773EA4EA.jpeg.a0688ad817d0b9b197fca5f8910098b5.jpeg
 

Clutch basket and showing oil pump drive. The chain is as slack as a slack thing but it does live in a oil rich environment. But a gear drive would have been nice - expense I guess.

B98CD10F-38E8-45FE-9008-F84CD38F271E.jpeg.33cef57915947508b2cb41bb60b26dc9.jpeg

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On 23/10/2020 at 18:37, theshootist said:

It looks like a very clean Daytona, so worth the effort. I ran a Sprint ST for a number of years and loved the triple, but always wanted to try the 955 Daytona. I went for the Sprint because it was a bit easier to ride being tall. 

I thought it was worth doing first time round, second time I’m not so sure.....

Do like the triple though, it has a slight rasp that is missing from the wheee sound of a four.

Now split the cases, still don’t know what’s wrong for sure but think that third and fourth are transposed on the output shaft....

37D0B696-BCC3-44C8-9E69-4824B5A01112.jpeg.b63bfe82d29357353ec71fa499ffdcc5.jpeg

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21 hours ago, SpringDon said:

 

I thought it was worth doing first time round, second time I’m not so sure.....

Do like the triple though, it has a slight rasp that is missing from the wheee sound of a four.

Now split the cases, still don’t know what’s wrong for sure but think that third and fourth are transposed on the output shaft....

37D0B696-BCC3-44C8-9E69-4824B5A01112.jpeg.b63bfe82d29357353ec71fa499ffdcc5.jpeg

Well outside my expertise, but you have the gears on the shaft the wrong way round? 

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On 26/10/2020 at 10:55, theshootist said:

Well outside my expertise, but you have the gears on the shaft the wrong way round? 

Well yes it seems  you’re right and are promoted to expert


The gearbox was assembled correctly according to the manual but when I stripped the selector drum and moved gears manually, I could count the revolutions and work out the gear ratio. Sure enough 4th came after 2nd.
The only way I could see it working was to switch the gears round on the shaft which would be wrong according to the manual and parts diagram. 
So just for laugh I looked at parts for the later 1050 engines and sure enough third and fourth are the opposite way. Part numbers are the same for the gears so the gears are the same, it’s just the selector drum is different so the selector slides in the opposite direction.

It seems the the last 955 engines used the transmission from the first 1050 engines, a fact conveniently missing from my £70 genuine triumph workshop manual.
 

Edited by SpringDon
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