Replacement of Clutch Springs/Plates

[Tat2demon]

Well, you got a good winter project then, there is a tech tip on converting the XS11 to a hydraulic clutch.

http://www.xs11.com/forum/showthread.php?t=13345

[BA80]

Castrol 20w50

If everything is in spec and it has new Barnetts it certainly should not be slipping.

Maybe the adjustment isn't right. I've struggled with adjustment before.

[Tat2demon]

If everything is in spec and it has new Barnetts it certainly should not be slipping.

Maybe the adjustment isn't right. I've struggled with adjustment before.

Not trying to detract from the OP post but as far as I can tell the adjustment is right. The plates were burned in a couple small spots so may just be time for new ones.

[BA80]

No one is detracting from the OP, simply discussing and elaborating on it.

There would have to be smoke billowing out of the crank case for the clutch plates to get burned in a wet clutch system. A slipping clutch can be caused by any number of things the least of which is worn or burnt frictions in this type of system.

In most cases a slipping clutch isn't cured by replacing the frictions but by the other things discussed here.

Just saying. No sense replacing parts unnecessarily.

[Rasputin]

One thing to note is that if you soak the steels over night in e-vapo rust they come out looking like factory. It will not remove blueing but, man it cleans them up nice, with no sand paper or stuff like that. I posted it a long time ago, showed pic's and all that but it escapes my old fart mind right now.

[IanDMacDonald]

Thanks for the evapo-rust tip Ras. I may do just that. The hydraulic mod looks fun, and it's something that has always intrigued me. I'll be okay without it though. Barnett springs as suggested by Greg and the rest will work great. Thanks fellas.

[Dan Hodges]

Spring Tension

Yeah, I've read through many posts regarding the EBC springs (including Nate's above), and was advised to stay away from those. They come too short, and are weak. I'll be going for some Barnett springs. Not sure I want HD springs though, as I hate a still clutch, and love the hydraulic clutches on my other bikes.

How was the tension of the available springs determined, mathmatically, guestimate or by a spring checker?

The stock clutch springs, Vesrah and EBC springs all have the same wire diameter, spring OD and are the same height however the stock and Vesrah springs have 10 coils while the EBC springs have 9 _guess which is the stiffest?

The only sure way to determine the tension of a spring is to test it on a spring tension tester because although springs may differ in the number of coils, type of wire and so forth only a test will be exact.

Some of these super stiff springs everyone talks about are designed for a diaphragm clutch which of course our XS doesn't have however it's true that a worn out clutch will slip but with enough spring tension it might not.

[jetmechmarty]

How was the tension of the available springs determined, mathmatically, guestimate or by a spring checker?

I got this at 650Central.com:


Heavy Duty Clutch Springs
Fits all XS
Set of 6, 14% stronger than stock
Spring free length is about 1.67".


Heavier Duty Clutch Springs
Fits All XS
Set of 6, 27% stronger than stock
Spring free length is about 1.61".


Heaviest Duty Clutch Springs
Fits all XS
Set of 6, 43% stronger than stock
Spring free length is about 1.50".

And that is what I know about clutch springs. It's blind trust for 650 Central.

[trbig]

Some of these super stiff springs everyone talks about are designed for a diaphragm clutch which of course our XS doesn't have however it's true that a worn out clutch will slip but with enough spring tension it might not.

That's an incorrect assumption, Dan. With Vesra and EBC, I was going through at least two sets of springs, and sometimes three in a riding season. Of all the clutches I've had apart and mic'd, I've only personally seen one friction plate slightly out of spec. and never seen an out of spec. steel. That in no way prevents them from slipping though. These other springs lose their tension quickly and the clutches will slip even with everything else adjusted right and in spec. Vesra and EBC will usually work for a little while and fix a slipping clutch, but they don't last. I've had these Barnett springs in for at least three full riding seasons now with lots of stoplight launches and wheelies without a single hint of a slip. You say they aren't designed for our clutches, but they are apparently exactly what these clutches need. They work, they work well, and they continue working long after the others fail.

[skids]

I have had Vesrahs in one of mine for a very long time (more than a decade). No problems with them. I will admit this is my naked bike, so it doesn't get as much use as the others and my riding time is split between 4 bikes.

[Dan Hodges]

That's an incorrect assumption, Dan. With Vesra and EBC, I was going through at least two sets of springs, and sometimes three in a riding season. Of all the clutches I've had apart and mic'd, I've only personally seen one friction plate slightly out of spec. and never seen an out of spec. steel. That in no way prevents them from slipping though. These other springs lose their tension quickly and the clutches will slip even with everything else adjusted right and in spec. Vesra and EBC will usually work for a little while and fix a slipping clutch, but they don't last. I've had these Barnett springs in for at least three full riding seasons now with lots of stoplight launches and wheelies without a single hint of a slip. You say they aren't designed for our clutches, but they are apparently exactly what these clutches need. They work, they work well, and they continue working long after the others fail.

With a stock motor the stock Yamaha clutch works as intended however the stock clutch and springs will slip on the dyno once you get into the mid 90's horsepower range.
I bought all the springs I could find and benched them and eventually finished my dyno sessions with new Yamaha disk and EBC springs and all was well.

I don't know what type of wire the Barnett springs are wound from but the Veshra, EBC and stock springs are wound from Oteva wire which is good stuff but it does and will lose some tension given enough abuse however I've solved the problem and have moved on to the final solution

[natemoen]

however I've solved the problem and have moved on to the final solution

Way to leave us hanging Dan......

[Dan Hodges]

With a stock motor the stock Yamaha clutch works as intended however the stock clutch and springs will slip on the dyno once you get into the mid 90's horsepower range.
I bought all the springs I could find and benched them and eventually finished my dyno sessions with new Yamaha disk and EBC springs and all was well.

I don't know what type of wire the Barnett springs are wound from and stiff they are but the Veshra, EBC and stock springs are wound from Oteva wire which is good stuff but it does and will lose some tension given enough abuse however I've solved the problem and have moved on to the final solution.

I have since begun using the inner spring from a set of KMotion valve springs which are about 15-20 percent stouter compressed than the EBC/Vesrah/OEM stuff however the KMotion springs are made of H-11 tool steel and do not lose tension.

I learned long ago that when it comes to mechanical things one can sometimes find more than one way to solve a problem and so it is with clutch springs.

My naked Special is a stout piece but I seldom do wheelies on it for the sake of wheelies or charge away from traffic lights like a man running from his sx-wife but I do like to race but on the Interstate where I can get it on with something that's worth racing and there is no point in racing my XS against a Busa or a Harley because a Busa would kill the XS and the Harley is out to lunch.

It is in my humble opinion that Yamaha was savvy enough to put enough clutch in the XS however if you add a bunch more power add a bunch more weight or both the clutch might need strengthening depending on the person sitting in the saddle and of course there are those who walk among us that could break an Abrams tank.

[BA80]

there are those who walk among us that could break an Abrams tank.

Yeah, I know someone in a little place called Ada that fits that description to a T.

[James England]

I would clean the driven plates with fine wet and dry. I've used it lightly on the friction plates too, in the past. Check the clutch basket and file off any ridges in the 'legs'.

Put new springs in. And a new clutch release bearing.

Re EBC springs....the problem with any forum is that someone may have a bad experience with something, posts about it, and it becomes carved in stone thereafter. One person says " don't us XXXX" and someone else quotes it and before you know it does the rounds and becomes 'true'. Clutch slippage on the bike originally the subject of the EBC post, could have been caused by several other factors.

As a matter of interest, does anyone have any actual evidence re these springs being "weaker" or less durable? Like a compression test? Or is it all anecdotal evidence?

Re hydraulic clutch....my XJR has one....the slave cylinders are notorious for leaking! I've already had to do mine....