Clutch dragging

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carrapi

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Hi all.

My new to me 99 gen 1 with 30k miles had a slipping clutch, so I took the cover off to take a look inside.

Everything was stock. The friction plates are still in spec (barely) and I scrubbed the steel plates. Also did an oil change.

Slipping stopped, but now it seems the clutch is dragging, specially at low speed, with noisy gear shifting, and I have a very hard time setting to neutral while stopped, with the shift pedal very stiff.
The problem is worse after ridding the bike for a while.

There were some dents in the clutch basket and boss, so I think that's what causing the problem.
IMG_20211218_144904.jpg

IMG_20211218_144818.jpg

Is this fixable with some sanding, or should I start looking for replacements?
 

desert_max

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I’ve seen worse that didn’t drag. If that is the cause of dragging, I would imagine that scuffing those sharp edges might prevent the plates from hanging. Certainly couldn’t hurt to try, beats buying another basket.
 

carrapi

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I’ve seen worse that didn’t drag. If that is the cause of dragging, I would imagine that scuffing those sharp edges might prevent the plates from hanging. Certainly couldn’t hurt to try, beats buying another basket.
Can it be done using some sand paper, without removing the basket from the engine? Or should I remove it to prevent filings from entering the engine?

Is there anything else to check that could be causing the stiff gear pedal?

I am with desert max but if you end up wanting a replacement I have them. [email protected]
👍
 

MaxMidnight

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Can it be done using some sand paper, without removing the basket from the engine? Or should I remove it to prevent filings from entering the engine?
Is there anything else to check that could be causing the stiff gear pedal?
I would be vary wary of anything that could leave an abrasive residue and certainly would not use sandpaper.

Any burrs could be dressed back with a fine file which, if done carefully, will keep the edges of the clutch basket flat. Again, you would need to be careful that the filings are all collected and don't get into the lubrication system.

If the clutch was clearing OK before disassembly then that would suggest the issue is not external to the basket but relates to what was done inside it.
One other thought, when you re-assembled the plates did they go back in as per the manual? (pp3-68 & 69 refer)
 

carrapi

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If the clutch was clearing OK before disassembly then that would suggest the issue is not external to the basket but relates to what was done inside it.
One other thought, when you re-assembled the plates did they go back in as per the manual? (pp3-68 & 69 refer)
I followed this Lvlhead's Vmax - Into The Clutch .
Looked at the manual, and it's much more detailed. Maybe I missed something...
I'll take a look as soon as possible!
 

MaxMidnight

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That's a good write-up but we have all probably inadvertently introduced faults when doing jobs so it's always best to go back over what's been done.
Good luck and let us know how you get on.
 

carrapi

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So I disassembled the clutch, and everything was installed correctly, with all the notches in the right places.

However, the inner friction plate, the last before the half plate has the tabs scratched
IMG_20211231_161741.jpg

I'm pretty sure that the plate wasn't like this before. What could be causing this scratches?
When I first reassembled it, I didn't used the same order for the frictions disk, don't know if it's relevant.

Anyway, I already order a new set of friction plates.
 

MaxMidnight

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I can't think of a reasonable explanation for that but looking at the tabs they appear worn down the edges? May be wrong as I don;t have a new plate to look at.
As you say the friction material is just within spec my inclination would be to change them to save the effort of another tear down in the near future.

When mine started slipping at a similar mileage to yours they were also just within spec. New plates sorted the issue.

While you are at it you could also replace the half plate with a full one but this would be at the expense of a noisier clutch at idle and a more clunky gear change.
Also I suspect the benefit is minimal, if anything, on a standard motor.
 

Parminio

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So I disassembled the clutch, and everything was installed correctly, with all the notches in the right places.

However, the inner friction plate, the last before the half plate has the tabs scratched
View attachment 81910

I'm pretty sure that the plate wasn't like this before. What could be causing this scratches?
When I first reassembled it, I didn't used the same order for the frictions disk, don't know if it's relevant.

Anyway, I already order a new set of friction plates.
The strangest thing to me about that picture is how much further down the tab on the left is worn than the tab on the right.

The tab on the right barely makes it to just short of half way while the tab on the left looks to have made it 2/3rds the way down the tab.

That would lead me to think that plate was moving back and forth - wobbling in fact. Or whatever it was rubbing against was moving back and forth.

Or maybe that plate is bent somehow?
 

carrapi

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I can't think of a reasonable explanation for that but looking at the tabs they appear worn down the edges? May be wrong as I don;t have a new plate to look at.
The edges are indeed worn, one more reason to change them

While you are at it you could also replace the half plate with a full one but this would be at the expense of a noisier clutch at idle and a more clunky gear change.
Also I suspect the benefit is minimal, if anything, on a standard motor.
I ordered a EBC plate set with spring, and I think it comes with the half plate. Like you said, my bike is all stock, so don't plan on replacing it for a full plate

Or maybe that plate is bent somehow?
Forgot to check that. I had very little time to tear down the clutch and put it back together, because for now the bike is my only way of going to work...
 

Radioguylogs

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You worried about this in your original post....Could the friction plate tabs have been catching on the worn "steps" in the clutch basket? Then it might become crooked and rub the tabs?

If this happened, that friction plate might even become bent.

Like Desert_Max said, I have seen nasty wear on the basket that didn't cause problems, but your evidence is so unusual.
 

carrapi

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The new friction plates have arrived, and they are soaking in engine oil before installation.

As I thought, it comes with the half plate.

It also comes with a new spring, 6% stronger than oem, according to EBC's website. I want to try the dd mod, can it be done with the half friction plate, or should I pick one of the old full friction plates?
 

Fire-medic

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I wouldn't bother with the DD unless you're drag-racing. I also would use a full-width inner friction disc instead of the half-width disc.

The used diaphragm spring and the one you have from EBC, would be a better DD mod than two BNIB diaphragm springs. Why? If you ever do two new diaphragm springs as a DD mod, and get caught in a traffic jam, you'll discover why. A used diaphragm spring loses a bit of tension over-time.

The half-width friction disc is how they eased the clutch-load when making ham-fisted downshifts by an owner. Look at it this way: you're gaining 6% more 'stiffness' from the EBC spring. You're going to gain about that much-more friction disc surface area from substituting a full-width friction disc for the OEM half-width friction disc. Maybe that's good-enough to satisfy your need for 'more-grip' from your clutch, without going to two diaphragm springs and the tiresome clutch-pull awaiting you.
 
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MaxMidnight

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I tend towards the 'if it ain't broke don't fix it' point of view.
IMO the OE clutch set-up in good condition works fine in a standard engine. As you have a new diaphragm spring I'd use it but retain the half plate.
The transmission will be quieter (doesn't rattle) at idle and the shifts will be smoother.
In the very unlikely event you still have clutch slip the full plate remains an option.
 

Ross L

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If it matters. I also have 30k miles on stock clutch. Started slipping( 4 th gear) after I added synthetic( yea I know) . I did the DD mod, didn’t touch the plates. Zero slip now. Only engine mods are ufo exhaust and jetted. I also don’t mind the increased lever pull. Good luck!
 

carrapi

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I installed the new friction plates, with the half plate. Only did a small ride around town and everything seems to be working fine.

Later this week I'll go for a long ride, and see if the slipping and the stiffness in the gears are gone.
 

DreamV4

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This is exactly what happened to one of my old GoldWings: discs wore out aluminum drum and everything was fine because they had their sliding spaces. You removed discs and installed them in different order, so worn out channels didn't match discs anymore. I would still pump clutch fluid before replacing drum.
 

carrapi

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You removed discs and installed them in different order, so worn out channels didn't match discs anymore
Also my guess.

Whit the new friction plates the clutch is working as it should. Still haven't tried the DD.

Thanks for all the help
 

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