I thought wet clutches were Indestructable.....

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Neither high engine speed/RPM nor high motorcycle speed will overheat the clutch. Slipping overheats the clutch. Holding the RPM , slipping the clutch and riding the brake will overheat it. Putting the bike in gear and riding off normally should not slip the clutch and riding along will cool the oil. This will lower clutch temperature by giving it time to dissipate the heat and let cooler oil circulate thru it. The heat in the oil that has been generated by slipping will dissipate and cool down along the outside of the oil pan where air circulates and where the oil can dissipate heat to the coolant and in the cooler. Riding it slow or fast could work but a nice clip will blow more air past the engine and oil coolers and cool the clutch down faster.

In the case mentioned sounds like the clutch was being slipped to ride ultraslow while keeping the RPM up to obtain instant torque if required and the speed was being controlled by riding the rear brake. Fine for ultra slow competitive conditions but too much too long will overheat the clutch. If you just need to ride slow "normally" in a parking lot or u-turn riding the rear brake will not hurt a thing....just give it throttle to stabilize the engine and don't slip the clutch since you don't need to go THAT slow.

Sounds like if the clutch failed due to this singular even then it is a safe bet that just the clutch plates themselves are affected. There might have been enough heat to affect the steel plates and the spring so it is the safe thing to replace them too. But you could probably get away with just the clutch friction plates.

Definitely soak them and use copious amounts of oil on them at reassembly.

If you reuse the steel plate you might want to burnish them lightly with 600 wet-or-dry sand paper.

Replacing the spring is the safe thing if you only want to go in there once but unless it is turned blue or discolored by heat it is probably OK.

Since the clutch has that many miles on it it might have been wearing anyway and did not have that much capacity anymore and the final friction-point exercise finished it off.

Definitely check the fingers of the clutch basket for notches or grooves worn by the clutch plate taps. Lightly dressing them with a file is usually fine unless it is severe.

As long as it is not slipping while you ride conservatively it will be fine and you will probably find that it will regain some capacity as you ride. You could still ride it forever unless it starts to slip under normal acceleration or road load then it would certainly fail completely very quickly.

However, I would recommend changing the oil IMMEDIATELY as you have obviously gotten the oil circulating thru the clutch quite hot and likely filled it with clutch material wear particles. A filter and oil change is an immediate requirement while you can order parts and replace pieces in the clutch much later in the game.

 
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The Wingsters that were active in drill teams and Top Gunn competitions were always at risk of frying their clutches (wet clutches, too). Sometimes it was simply glazed. You might want to check it out to see if they mic withing tollerances and if a simple scuffing of the friction plates will fix things up.

 
I've replaced lots of clutches in my day. Hopefully I can give you some shortcuts.

90% of the clutch failures I've seen are because of steel plate warping. When you pull the whole clutch apart, you'll see blue or black hotspots on the steels.

Generally, the fiber plates are still fine. They tend to resist warping.

Fiber plates have oil release slots in them. "Tread" if you will. If the slots are still visible, then the fiber plates are still useable.

I sand the fibers on a flat plate just to eliminate any glazing. Then I replace the steels. The steels are the trick.

Obviously you can replace the entire plate package, both fibers and steels, but in a couple of decades of racing and wrenching in the aftermarket, the method above has always worked.

YMMV.

 
Skooter needs a Harley! :rolleyes:
What do you think I sold to buy my FJR, you crazy la-la land hippy?

She sure was puuuurty, though....................

Harley-RightRearview.jpg


 
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Like others said the clutch job is easy. Make sure you stack all the frictions and steels up in one stack and check the overall thickness to make sure it is in spec. while they are dry. Many times the friction plates can differ by just enough to make the whole stack to thick.

Before you install them, put the fibers in a ziplock with some clean oil that you use in your engine. It pre-conditions them to being in oil. Also, you will want to check the stack again and make sure it didn't swell too much and go out of spec and be too thick.

Ran into this many time with the race bikes. If it is too thick, you may have to find the the plate (or plates) that are thicker then the others and take them out of the stack and re-use one or two of the old plates that are still flat and don't look overheated to get the stack in spec. Only had to do this a few times on a race bike.

If the stack is not within spec the clutch will not engage or disengage properly.

 
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I thought wet clutches were Indestructable.....
Uhm...Eye heered the nuthin wuz un-dee-constructed-able iffen summon wuz reely reely motorvaitid tuh roowin et. Souns lak yewer testin thangs purdy good win yere sippy-slidin thet dang ol' thang fer ours. Wutcha thank, ets a dang ol' lektric clutch er sumpin? Sheesh! :eek:

Eye betha thet dang ol' dry slippity clutch uh thet torky V-twin woods bin purdy well dun, tew. Thet's iffen yew kudda pulled thet lever fer ours, :D

 
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She he sure is shiny and gay purty! That bike come wid chaps or didya have ta buyem extra? :)
Hell, he had those chaps already. That's Skoot, there, fifth from the left. Those other fellas are his "friends."

Village-People-012.jpg


 
Skooter needs a Harley! :rolleyes:
What do you think I sold to buy my FJR, you crazy la-la land hippy?

She sure was puuuurty, though....................

Harley-RightRearview.jpg
O.

M.

G!

That has to be the gayest paint scheme ever!!! Please don't tell me you had matching beanie helmet and chaps to go along with that, that thing! Oh well, I guess rainbow boy's gotta make a statement.

:lol:

 
Skooter needs a Harley! :rolleyes:
What do you think I sold to buy my FJR, you crazy la-la land hippy?

She sure was puuuurty, though....................

Harley-RightRearview.jpg
Hey Admin, did your thread get hi-jacked? :unsure:

EDIT to return to thead:

I've replaced many clutches in various dirt and street bikes. It isn't all that difficult. You can buy aftermarket clutch basket holders for far less than factory parts. Good luck Skoot!

 
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