Clonking noise from gear box?

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mobil1
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Clonking noise from gear box?

Post by mobil1 »

Can anyone help please.
I came back from a trip to Rimini last year on the RU and it's developed a Clonking sound when wheeled about.
It sounds like you have a slack chain with a tight spot catching the frame but it's in the engine. Approximately where the gearbox is.
Any ideas? I'm hoping its not what I think.
I have a spare engine if I need but that in need of a top end overhaul.
Thanks in advance for any help
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Stig
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Post by Stig »

Bearing of output shaft or big end? :crybaby:
AKA Bald headed b'stard
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mobil1
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Post by mobil1 »

Thanks Stig.
I think it's the out put shafts as it's a bit wobbly. And its not knocking like a big end would. At least I hope not.
I've thought it might be a bent fork selector tbh. I miss geard at at high speed.
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Post by mobil1 »

Either way I guess it's an engine strip. 😭
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Post by Jay762 »

Yup no way around that, might as well put in a sixth gear whilst its apart :unibrow:
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mobil1
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Post by mobil1 »

Am toying with the idea 😎
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YAMAEXUP
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Post by YAMAEXUP »

What's the gearbox sprocket like?

Does the chain lift off the rear sprocket by much, indicating a stretched chain?
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Post by YAMAEXUP »

Also, if it doesn't clonk when you pull the bike backwards, it's not the gearbox sprocket bearing
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Post by mobil1 »

Hi. The chain n sprocket are all good n new before Rimini. I've not done more than 100mile since. I have retensioned it and it's still Clonking . No play in the chain or sprocket. If I remember rightly it doesn't clonk going backwards. It's on stands at the mo as I've just fitted shorter dog bones. I'll check backwards when it's back on the floor but I'm pretty sure it doesn't.
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