Author Topic: Gearbox noise...  (Read 622 times)

Offline Padsta33

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Gearbox noise...
« on: 27.08. 2016 20:22 »
I've developed a noise think it's coming from primary side. It's noticeable in neutral and 2nd gear. Sounds like when your trying to select neutral and somthings still spinning.
Have I damaged something?

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Online muskrat

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Re: Gearbox noise...
« Reply #1 on: 27.08. 2016 21:45 »
G'day Paddy.
That's a strange one. My 1st thought is a bent selector fork. Is it a ratcheting type sound?
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
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Re: Gearbox noise...
« Reply #2 on: 27.08. 2016 23:28 »
i would certainly check the mainshaft nut is tight both ends as a precaution if the oil level is correct.

Offline Padsta33

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Re: Gearbox noise...
« Reply #3 on: 28.08. 2016 07:37 »
Yes Muskrat it is a ranching sound kind of.
It's like when you pull àway and select 1st from neutral and it doesn't engage, if that makes sense.
Sorry to sound dumbass but where is the main shafts nut too?  (Both ends)

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Offline Padsta33

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Re: Gearbox noise...
« Reply #4 on: 28.08. 2016 07:38 »
Also it only started last ride out after changing   down at too high revs. If that helps..?

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Re: Gearbox noise...
« Reply #5 on: 28.08. 2016 16:09 »
hi, its hard to work out whether something has broken, worn or come loose from your postings. one end of the mainshaft is the clutch nut and the other is behind the gearbox outer cover where the clutch pushrod goes through and should be held with a tab washer. the a10 gearboxes are pretty robust but its easy to take the front cover off and tap with a copper mallet and have a look for endfloat on the shafts. another suspect is bearing failure but to go further you would have to take the clutch of first.

Offline Padsta33

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Re: Gearbox noise...
« Reply #6 on: 28.08. 2016 18:25 »
hi, its hard to work out whether something has broken, worn or come loose from your postings. one end of the mainshaft is the clutch nut and the other is behind the gearbox outer cover where the clutch pushrod goes through and should be held with a tab washer. the a10 gearboxes are pretty robust but its easy to take the front cover off and tap with a copper mallet and have a look for endfloat on the shafts. another suspect is bearing failure but to go further you would have to take the clutch of first.

Thanks for info. Just had another look. Run her up and once warm, from stationery, selected 1st/2nd and back to neutral, all seemed fine but tried same sequence again and while in neutral the noise started.  ( it does this while stationary while in 1st with clutch engaged occasionally) if you operate the clutch a couple times it goes away. It's a kind of really loud ratcheting sound, almost like if you pull the kick starter down whilst it's running, but louder. I took off the primary case and only thing I noticed was the metal plate that sits around the clutch was warped in places (if that makes sense)
Any advice appreciated before I'm going to have to take to garage mechanic.
Cheers
Paddy.
Oh also if it's starts this noise, if revved up it goes away.

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Offline Padsta33

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Re: Gearbox noise...
« Reply #7 on: 29.08. 2016 10:56 »

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