Clutch plate thickness problem

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Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Clutch plate thickness problem

#1 Post by Hooligan » Wed Apr 12, 2017 8:05 pm

So, I am part way through replacing the entire clutch pack (steels and fibres) on my F2 RZ and have run into a slightly strange problem.

First I only replaced the fibres with a set of EBC heavy duty plates. Sadly the steel plates seem to be warped as it is impossible to adjust the clutch so that it is free with the lever pulled in and also doesn't slip at high rpm. I can choose one or the other but not both.

So I ordered a set of steel plates from Yambits. Not really sure who actually makes these plates.

When I installed the new steels with the EBC fibres and screwed down the springs I discovered and interesting problem. The clutch couldn't be pulled at the lever. It was like something was badly jammed. I pulled everything apart to confirm it was all together properly but the problem persisted.

When I backed off all 6 springs a few turns, suddenly the clutch worked fine. :smt017

It took a bit of thinking and had to measure up a few things but it turns out the new clutch pack is too thick. This causes the pressure plate to sit slightly further away from the basket fingers. The practical result being the springs are completely compressed when their keepers are screwed home.

In a stock clutch, the distance between the bottom of the pressure plate recess and the top of the basket fingers is roughly .920". The clutch springs are fully compressed at .800". When I measured up my new clutch, this distance was .810". Thus the springs were already fully compressed and the pressure plate could not move at all to release the clutch.

I called up the RZ Oracle, Rory to ask if he'd ever run into this issue and he was of no help at all. :smt012 My solution is actually fairly simple. I will run off a set of .120" thick washers to sit on the spring keepers and fit inside the springs. This will move the pressure plate away from the basket enough to allow the clutch to operate as it should. Benefits of having my own lathe. :smt023
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

User avatar
OldTZracer
Posts: 240
Joined: Thu Aug 05, 2010 2:21 am
Location: Alberta Canada

Re: Clutch plate thickness problem

#2 Post by OldTZracer » Sat Apr 15, 2017 12:20 am

Make sure you check your clearance to the inside of the clutch cover's ribs & protrusions...
"...its a 2-stroke ya twit - Its supposed to smoke..."

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#3 Post by Hooligan » Sat Apr 15, 2017 12:59 pm

OldTZracer wrote:Make sure you check your clearance to the inside of the clutch cover's ribs & protrusions...
Done. No contact. :D
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Clutch plate thickness problem

#4 Post by Bare » Tue Apr 18, 2017 12:49 am

Are you using RZ steels?
Other Yama Steels fit / seem identical.. but are significantly thicker.
Strange that a steel is allegedly bent .. Checked it with a straight edge and feelers?
OEM yama steels are a whole world better quality than Aftermarket ones.
Even recycled yama steels are preferable
Best have genuine reason for replacing them.. unless you like repeated clutch work.

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#5 Post by Hooligan » Tue Apr 18, 2017 1:04 am

I ordered RZ steels from Yambits.

The problem with the old steels was that clutch could not be adjusted to disengage properly and also not slip at high rpm. I had to choose one or the other. Also the clutch engagement point would change dramatically as it warmed up from being ridden. Something was seriously wrong.

Now it has new steels and new fibres so it should work properly.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Clutch plate thickness problem

#6 Post by Bare » Fri Apr 21, 2017 12:28 am

Shame... Fair chance the Yambits steels are not actually made of Steel :-) Unless in sealed Yama baggies?
Again: Steels, unless Bent or Blued or both are Lifetime parts.
My guess is that your frictions were Faulty and /or an ahem... mistake occurred on assembly.

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#7 Post by Hooligan » Tue Apr 25, 2017 7:53 pm

Bare wrote:Shame... Fair chance the Yambits steels are not actually made of Steel :-) Unless in sealed Yama baggies?
Again: Steels, unless Bent or Blued or both are Lifetime parts.
My guess is that your frictions were Faulty and /or an ahem... mistake occurred on assembly.
The original clutch was fooked. I replaced the fibres and it did improve somewhat but was still generally fooked, especially when the clutch heated up from use.

Thus far the new steels seem to work fine although I've only ridden around the block a few times to make sure there were no major issues. At least now the clutch properly disengages when the lever is pulled in.

Assembling a clutch isn't exactly rocket science.

If not steel, what would you surmise the Yambits steels are made of? There are only so many materials that "steel" clutch plates could be made of. They most certainly are not aluminum or cottage cheese for that matter. :smt003
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Clutch plate thickness problem

#8 Post by hondaror » Fri May 19, 2017 6:59 pm

Oh, Peter, I have to retort. First off, I am not the RZ Oracle, I happen to own just more than two handfuls of RZs, of which I'm starting to get aquainted with. Secondly, like Brian (OldTZracer), I told you to watch for case interference on the three internal nubs. Then I told you that, I believe the RZ shares the same clutch case as the RD/LC, which you confirmed that I was right. Nuff said. Very glad you got it all sorted.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#9 Post by Hooligan » Fri May 19, 2017 9:20 pm

Rory, don't sell yourself short. You've had an answer to every question I've asked so if that doesn't fit the function of an oracle I don't know what does? ;)
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Clutch plate thickness problem

#10 Post by hondaror » Sat May 20, 2017 2:01 am

You are very kind dear sir!...and extremely devoted to your cause with regards to your bikes. Admirable!
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Bare
Posts: 1196
Joined: Sun Jan 29, 2006 2:18 am
Location: vancouver

Re: Clutch plate thickness problem

#11 Post by Bare » Sat May 20, 2017 11:23 pm

Hooligan wrote:
Bare wrote:Shame... Fair chance the Yambits steels are not actually made of Steel :-) Unless in sealed Yama baggies?
Again: Steels, unless Bent or Blued or both are Lifetime parts.
My guess is that your frictions were Faulty and /or an ahem... mistake occurred on assembly.
The original clutch was fooked. I replaced the fibres and it did improve somewhat but was still generally fooked, especially when the clutch heated up from use.

Thus far the new steels seem to work fine although I've only ridden around the block a few times to make sure there were no major issues. At least now the clutch properly disengages when the lever is pulled in.

Assembling a clutch isn't exactly rocket science.

If not steel, what would you surmise the Yambits steels are made of? There are only so many materials that "steel" clutch plates could be made of. They most certainly are not aluminum or cottage cheese for that matter. :smt003
Yambits stuff is often of bottom feeder quality. Regardless of Brochure babbles.
Was being facetious out of deep disrespect for all things "yambits'.
Again: unless visibly damaged there is NO substitute or need for replacing OEM yama steels... period.
Clearly you've now sorted your problem.
Reads as if it was of the user created variety or ?
G'luck.

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#12 Post by Hooligan » Sun May 21, 2017 1:17 am

I have not had that kind of experience w Yambits stuff. Been quite happy with majority of things I've purchased from them.

Once again, assembling a clutch isn't rocket science. I've done lots of them and never had this kind of problem. Condition persisted until I replaced the steels.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Clutch plate thickness problem

#13 Post by hondaror » Sun May 21, 2017 12:59 pm

Bare wrote:Shame... Fair chance the Yambits steels are not actually made of Steel :-) Unless in sealed Yama baggies?
Again: Steels, unless Bent or Blued or both are Lifetime parts.
My guess is that your frictions were Faulty and /or an ahem... mistake occurred on assembly.
I find that to definitely not be the case. I've pulled apart more clutches than I can count with toasted steels. What gets me, is how they got to that point. My LC, I replaced springs twice. The second time I used TZ250 springs, because I had them from my TZ. Never replaced them again after that. My bike had over 100,000 kms, with a Barnett friction replacement about half way. I always ran 1000ccs of tranny oil, not the 1500 it called for. No baked clutches, and I drag launched from a lot of lights, front wheel in the air using major slip. I guess it's all about how you ride, and whether or not you're in tune with the bike. So many people have no idea.
My steels were original, but seen so many wharpped and blue ones.
Last edited by hondaror on Sun May 21, 2017 5:48 pm, edited 1 time in total.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Hooligan
Posts: 1966
Joined: Mon Aug 20, 2012 1:37 am
Location: Calgary, Alberta

Re: Clutch plate thickness problem

#14 Post by Hooligan » Sun May 21, 2017 2:26 pm

In the case of our bike, the clutch engagement would change drastically from a cold motor to a hot motor. If this is not an indication of warped steel plates then I don't know what would be. Replacing the steel plates made this issue go away, which would highly suggest it was the steels causing the issue.
'82 RD350LC in '81 colours, OEM pipes, UNI filters
'85 FZ750

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