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Noisy in low gears

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Hi,

Before I tear my transmission down, which I'm in no hurry to do, I wondered if this might ring any bells with anyone.

My MKIIA 850's transmission makes a noise in first gear that sounds a bit like, say, reeling in one of those electrical extension cables where you rotate a knob on one side. Or like rubbing a lump of metal on fairly coarse sandpaper with a circular motion, only with a deeper tone. It's quite loud, and speeds up as I accelerate, as you might expect. It seems to be louder in second gear, but starts off slower again, as though it's somehow related to the change of gear, maybe something on the layshaft. It's quieter again in third gear but otherwise behaves the same, and seems to be absent in top, although maybe it's masked by engine noise and the wind. If it *is* absent in top, maybe it's because that's a direct drive from the mainshaft to the output, if I remember correctly, meaning whatever else in the gearbox is taking a rest.

It feels as though it's been doing it a long time â I've put something over 20,000 miles on the bike since I bought it â but it's getting to the point where it's so loud it's embarrassing, not to mention rather scary. Any thoughts? TIA

Colin

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Finally! After two straight days of dry weather, the Beast lives again! At a standstill, I have to work slightly harder to find first from neutral than I did before, but otherwise all seems well, and the transmission is almost unheard â I'd say that's a result!

I gave up on the new gearchange ratchet spring after a few attempts at bending it into shape and just stuck the old one back in, I was only replacing it out of caution and it works fine. The only other thing, endfloat on the layshaft, with the roller layshaft bearing fitted, is virtually non-existent, and no shims are fitted. I ended up pushing the inner race onto the layshaft until the shaft was proud by a few thou â machining on the inner face of the box suggested this would be ok, but obviously I didn't want to go too far. The old inner race was, as I recall, flush with the end of the layshaft.

I believe any endfloat is expected to close up as the box warms up? My first ride was only 5 miles or so to satisfy myself that everything worked and the noise had gone, then I went 20 or so more just to enjoy it, including a few miles on a fast dual carriageway. No complaints from the gearbox. I think I'll give it an early oil change, and expect to see specks of metal as I drain it, but my obvious hope is that it'll just settle down. Unless anyone knows better?

Anyway, thanks again for all the help and comments. After three weeks of all sorts of ups and downs, fingers crossed that I don't have to go into the box again for many more miles.

One last off-topic thing, I fitted a pair of Viking factory-facsimile peashooters today that had been off for re-chroming â a long story â but my god they sound fantastic compared to the ones of dubious origin that were on the bike when I got it all those years ago. A different, fruitier tone and much more lively sounding, but I don't think they're much louder if any. And they're beautiful. Lucky me! Laughing

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Hi ,

I bought a 850 Mk 111 a couple of years ago and i struggled finding neutral, but the more i used the bike the easier it got and now its silky smooth.

Mind you the bike had been stood for many years, looked after, but not run .

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Previously andrew_windsor wrote:

Hi ,

I bought a 850 Mk 111 a couple of years ago and i struggled finding neutral, but the more i used the bike the easier it got and now its silky smooth.

Mind you the bike had been stood for many years, looked after, but not run .

Thanks for the tip Andrew, here's hoping for silky smooth! Cheers.

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Previously Colin Peterson wrote:

I think I'll give it an early oil change, and expect to see specks of metal as I drain it, but my obvious hope is that it'll just settle down. Unless anyone knows better?

I fitted one of AN's magnetic drain bolts to my MK3 gives a clear indication of any impending problems.

Regards

Katherine

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Thanks for reminding me Katherine, I just fitted one of those! But I'd forgotten already ... Do they do genuine factory brains?! I could do with one of those too ... Wink

 


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