Grabbing clutch

Hi - there seems to be a lot of info scattered around the forum about various clutch problems over the years from faulty clutch basket rivets to oil grades and replacement parts but it does seem to be a significant problem for a lot of owners and could do with pulling together in a structure somewhere.

While we muse on that my immediate issue is that after nearly 10000 miles in just over 2 years my 2017 CR clutch started to very occasionally make what can only be described as a loud mechanical squawk when moving off. Not always and not repeatable. This has got steadily more frequent and now seems to be associated with an abrupt grab and several near tail-enders into the car in front. The rest of the time it is sweet as anything and always has been so I am loath to start stripping down in case there is a part needed which is not available and the bike is totally out of action. I am using the standard semi synth which was recently changed and the lever action feels fine so along with the mechanical noise I don't think its the slave cylinder sticking. If it is associated with plate wear I would happily replace the complete assembly but nobody seems to have a definite answer on spring and plate compatibility.

Any suggestions?

This problem does sound familiar doesn't it ? Others have had this I know I read about it right here on this forum. The good thing is that the clutch plates are immediately available after removing the primary case cover . Nothing else need be disturbed . In this case a replacement of the steel plates was necessary , and also look for notching on the basket , hub and other friction plates . I just purchased a set of the CK2255 friction plates and CSK126 spring set of 6 . They look correct but have not tried them , just based on RoadRocket's findings from EBC .

Ok thanks for this info - do we know that the clutch baskets through the years take the same plates? And if there is a problem with the basket can another be adapted? Let me know how you get on - at the moment I am torn between opening it to make sure nothing is going to cause more damage, knowing I am a bit of an automotive hypochondriac, and at least now it is useable with a bit of caution.

The notching is a possibility - plates sticking and rattling together????

Is it always upon the release of the clutch that you see the problem ? Never on the engaging pulling lever in ?

TonyA said:

Is it always upon the release of the clutch that you see the problem ? Never on the engaging pulling lever in ?

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Never. The squawk happens as I'm actually pulling away and moving so there is quite a bit of bite at that point. I seem to remember one post a few years back from Richard CNW relating to a shim/spacer being loose between the bearings in the clutch and they were going to put together a kit for Ollie to distribute. Could be a combination of problems?

I hope not for your sake because there is more disassembly then. There is already a OD circlip and spacer in there separating the two bearings.

This is my dilemma - I'm assuming that could wait for the winter without any real damage. Maybe as you say inspect the basket and plates. As I have a queue of bust things to fix when I strip something down within reason I just spend the money and replace parts to avoid having to go in again.

Clive said:

Never. The squawk happens as I'm actually pulling away and moving so there is quite a bit of bite at that point. I seem to remember one post a few years back from Richard CNW relating to a shim/spacer being loose between the bearings in the clutch and they were going to put together a kit for Ollie to distribute. Could be a combination of problems?

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Hi Clive, I have the same problem with the clutch noise does not do it all the time only if you slip the the clutch a bit more when taking off. Checked the clutch slave cylinder and thrust bearing, stripped the clutch plates out and cleaned and clean oil. I am laid up at the moment so might have another look at it. Could be a gear box thrust bearing other side of the clutch basket ! Good clutch action otherwise.
2016 Sport

After speaking to David C. today he said should be ok (safe) to drive for now. But may be the rear cush springs on back side of basket loose or sagged (these should be tight upon inspection) . He stated that the bearing spacer problem caused a unwanted side load on the bearings inside basket . After tightening the center hub nut too much side load on the bearings resulted and premature bearing failure. I would think with 10,000 miles on your bike this is not it.. He said his bad bearings occurred within 2,000 miles . He said the "squwak" should be quick when you take up the lash in the clutch basket springs / hub upon take off . Does this sound like what you are hearing ?

Something simple to check, with no parts required, would be the lubrication of the ball bearing located between the clutch slave cylinder and the actuating rod. 3 bolts holding the primary drive cover, care required as spacing washes the ball bearing will drop out when you remove the cover.
Clean everything, check your sprocket whilst your there and get a dollop of grease on the end of the rod to hold/lubricate the ball bearing.
If nothing else it will keep you amused for an hour during the lockdown! But I hope it helps.

TonyA said:

He said the "squwak" should be quick when you take up the lash in the clutch basket springs / hub upon take off . Does this sound like what you are hearing ?

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Sounds just like it. Thanks so much for this valuable advice - I will have a look in the manual for these - I assume these are going to be tricky to get hold of at moment so shall delay the strip down. I would probably get all the parts together I can replace and do them all. Not a very scientific way to isolate the cause but less strip-downs.

DODGY DEN said:

Hi Clive, I have the same problem with the clutch noise does not do it all the time only if you slip the the clutch a bit more when taking off. Checked the clutch slave cylinder and thrust bearing, stripped the clutch plates out and cleaned and clean oil. I am laid up at the moment so might have another look at it. Could be a gear box thrust bearing other side of the clutch basket ! Good clutch action otherwise.
2016 Sport

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Hi - yes as I always say with these things - if you've got the problem so have many others. I assume nothing notchy visual on clutch basket to cause sticking? Interesting comment from TonyA on springs.

StuartSF2015 said:

If nothing else it will keep you amused for an hour during the lockdown! But I hope it helps.

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No fun like half a day looking for a lost ball bearing on the garage floor! Yes the easy things are worth doing thanks.

TonyA said:

After speaking to David C. today he said should be ok (safe) to drive for now. But may be the rear cush springs on back side of basket loose or sagged (these should be tight upon inspection)

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Been looking on CNW and Norton manual but can't seem to see these springs...

This is the iffy looking spring from my clutch basket that had the end broken off & went for an excursion all round the primary side & gearbox, & damaged the balence shaft & 4th gear SO YES check it out throughly!

Hello Richard . Thank goodness that you got it fixed before Norton went under ! And they did a good job and for a reasonable price correct ? There were some very good people working there and its a shame this bad stuff had to happen at all . Do you think that Jinlaing or whoever will get rolling on parts for these bikes ?

Yes Tony , dunno wat I would of done if it happened now , couldn’t even ship over to Richard 7 & dad , the bike was at factory for almost 8 weeks,& there 7 weeks before they had a chance to look at it,when I picked it up it was Rob Jameson’s last day , Ashley mechanic had done the repair , at the time I got the gut feeling of the saying they have in cricket ,” we’re batting as well as can with the bowling we’re being given “
There didn’t seem enough people to fix things , & we know why now , Ashley left the month after I believe.

Was there ever a determination as to why the spring failed?
Clutch assembled improperly, substandard spring material, etc...?

It was at 16,000 mile & one of the highest miles they seen at the time , & bad luck/one of them things basically!

BLIGHTYBRIT/SF said:

This is the iffy looking spring from my clutch basket that had the end broken off & went for an excursion all round the primary side & gearbox, & damaged the balence shaft & 4th gear SO YES check it out throughly! View attachment 15315View attachment 15317

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It would be interesting to know before your failure were you getting the clutch noise when the clutch was released which some of us are experiencing.