Clutch basket bearings.

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chas b
Cucciolo - the Lil Pup
Posts: 21
Joined: Thu Aug 12, 2010 2:57 pm

Clutch basket bearings.

Post by chas b » Mon May 14, 2018 11:31 am

Hi Chaps.
My MHR had got noisier recently ( not owned it for long and not done many miles on it). Removing the clutch cover I found the clutch drum had a lot of play ( not up and down on the shaft but rocking). So not the usual loose nut. I replaced the bearings with new ones, making sure that I assembled the bearings the same way as the old ones that I removed. I reassembled and found that the 'rock' was still there. I'm now wondering if the old bearings had in fact been fitted wrong and so I replicated the mistake? None of the online diagrams that I can find show the correct assembly clearly, hence my question.
PS long time 900SS owner but I've never had trouble with these bearings before... just had a thought. If no-one can help me here I'll take a look at the SS clutch. But hopefully someone can save me the trouble.

Cheers
Chas.

chas b
Cucciolo - the Lil Pup
Posts: 21
Joined: Thu Aug 12, 2010 2:57 pm

Re: Clutch basket bearings.

Post by chas b » Wed May 16, 2018 2:39 pm

Well I checked the clutch drum from my SS, I have fitted the bearings correctly. So am at a loss to explain the excessive movement.
Ideas anyone?

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Craig in France
Cagiva Elefant
Posts: 833
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Clutch basket bearings.

Post by Craig in France » Wed May 16, 2018 11:17 pm

Hi Chas,

Can you just please clarify which piece you're referring to?
Clutch.jpg
In the scan above, the "clutch drum" is item 34. But this has no bearings in it. It's a fixed non-rotating piece, splined on to the gearbox shaft. If this is rocking on its shaft, then you have wear in the splines.

The piece with bearings is item 30, the clutch housing or basket. But this is engaged with the gear on the crank. So can't really rock.

Or am I missing something?

P.s A thought. If your plates are out, and you have the bike in gear and you find that the clutch drum (piece 34) and its shaft are rocking, don't worry. That's just the normal take up in the gear box.

Ciao

Craig

chas b
Cucciolo - the Lil Pup
Posts: 21
Joined: Thu Aug 12, 2010 2:57 pm

Re: Clutch basket bearings.

Post by chas b » Thu May 17, 2018 12:14 am

Hi Craig, thanks for taking the time to answer. I've always used the term 'basket' or 'drum' to mean the same part so I've learned something. I really mean part 30 with the two bearings in it. I have replaced these with new ones and refitted the thrust washer,basket,drum, tab washer and tightened the centre nut to correct torque. Holding the basket I can rock it and see it move independently of the drum, I am not turning it but pulling and pushing on it directly as you look at it(I have not refitted the cluch plates at this stage). Surely it can only be slack in the bearings but why?

wdietz186
888
Posts: 677
Joined: Sun Sep 10, 2006 4:40 pm

Re: Clutch basket bearings.

Post by wdietz186 » Thu May 17, 2018 7:12 pm

It's been a while and I don't have one handy but I recall a shim or two between the bearings in the basket and only 1 locating lip in the basket. That might be the source of the play if the fit of the bearing isn't tight in the basket and the bearings aren't butted together with the hub tight. OR the shaft end play is way loose. How much play is there? Does the hub move in and out? I think the shaft end float is supposed to be about .008"-.010"

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Craig in France
Cagiva Elefant
Posts: 833
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Re: Clutch basket bearings.

Post by Craig in France » Thu May 17, 2018 10:39 pm

chas b wrote:
Thu May 17, 2018 12:14 am
I really mean part 30 with the two bearings in it. I have replaced these with new ones and refitted the thrust washer, basket, drum, tab washer and tightened the centre nut to correct torque. Holding the basket I can rock it and see it move independently of the drum, I am not turning it but pulling and pushing on it directly as you look at it.

Surely it can only be slack in the bearings, but why?
Ok, Chas, that might help.

Here's what should be in your clutch. From what you say, it seems you are missing either part #38 or #55. This would explain the slop in the fit.

[URL=https:///]Image[/URL] image upload

HTH

Craig

ducadini
750 Sport [BEVEL]
Posts: 225
Joined: Sat Jul 31, 2004 8:54 am
Location: Antwerpen

Re: Clutch basket bearings.

Post by ducadini » Thu May 17, 2018 11:01 pm

We all know that manufacturing in those wasn't Always upto the standard we use today.
I think it is plausible that with a crankgear a bit worn, a drumbasketgear a bit worn and the distance between crank and inshaft a tad to the maximum tolerance and a set of not too fresh bearings, the drum could be made to swivel a bit.
Perhaps Earlier in its life, one of the bearings seized, was replaced and the shaft was "repaired" with a bit of sanding of the grooves. A bit more free play and the road is set.

I know that while doing sprints uphill, I found traces of the drum of the clutch getting out of line (due to the helical gear and the force it apllies) and touching the crankcase. All parts were standard BUT virtually never original sets.

Don't forget we're talking 30+ years old stuff here that wasn't meant for cruising.

ciao
ducadini
Nego i ricordi peggiori
Richiamo i migliori pensieri

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