clutch pad thickness before replacing?

spunout

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i honestly did my best to search the topics before resorting to post a new one, here: http://www.motoredbikes.com/viewtopic.php?t=939
http://www.motoredbikes.com/viewtopic.php?t=1202&highlight=clutch+pads
and couple others, but i still have two questions...
1-how thin can pads get before they have to be replaced?
2-can just the pads be replaced, or do i have to get them with the gear they're on?

here's mine
1152_clutch_1.jpg

for some reason the shadows make it look like the pads are all fat-n-sassy, but they're actually a little less than 1/8" thick. I know they're smooth, and im going to use the advice i found in those topics to rough them up and give the pressure-plate nut a couple extra turns. but my main deal is those two questions. thanks

Pressure plate front
pressureplate.jpg
 
spunout...you've taken this to a much better techie level, the right questions should get us the right answers 8)

excellent pic! any chance you can spare one of the pressure plate, too? edit: thanks man :)
 
Those friction material pads look good to me.

Things I might do.
Place a straight edge across the pads and measure by feeler gauge how much clearance there is from the center hub. As long as there is about .015" I would hold off on repair. (I think that is where the pressure plate will hit and cause clutch slippage.)

Next I would trim, by knife, the bits off the outter edge of the pads. That little ledge, it does nothing. Do not grind on those pads because being from China it just might be asbestos, a very good clutch 'n brake material but a real health hazard when inhaled.

Next I would break the surface of the pressure plate by lapping it on a sheet of 220 wet or dry. Use a flat 12"sq flooring tile or thick piece of glass. Lay this flat piece on a very damp towel next to a sink filled with warm soapy water and have at it. Back and forth is OK, just rotate it every once in awhile. Keep the wet or dry wet. Do it till 80+% of the surface is dull looking. It any of the edges are a dead 90, chamfer them because they will squeege away the important soapy water that aids in the cutting action. Use light hand pressure, do not force the plate into the wet or dry.

To change the pads. Someone here needs to find the right thickness of woven friction material. Generally it is asbestos (illegal) woven with lots of brass threads in it.
I would remove this gear, place it flat on the bench, use a very sharp chisel to break off the old pads a piece at a time, clean the surface as best I could (a little roughness won't hurt), then bond on new pads with JB weld. JB weld transfers heat well and is good to about 450F.

I would put the JB on the new pads, set them in where they belong, place the pressure plate on top of them, then clamp the plot together for 36 hours. Less if it is very warm. Do not use heat or direct AZ sunlight to quicken the set-up time as it may weaken the ultimate bond.
Leave this clamper together, facing up because JB is low viscosity. Leave it alone, do not even look at it for 36 hours. :)

A newly surfaced pressre plate will offer a very quick lock-up. Do not abuse it. Snap clutch starts with these motors is a fools game. (I did ride old British bikes.)
To clean off oil or grease, nothing is better than aerosol brake clean, you guys know that. But you may not know that it will get grease out of your darling's carpet. Test first in a hidden area, like inside the closet before using on any main area of the rug. This has saved me more than once. :cool:
 
Run it until it won't grip any more, then replace the plate, they aren't that much money and pretty quick to replace compared to the above method. :)
 
I was not trying to be technical.
spunout PMed me into this thread. :cool:

If I had a quiet gear set that broke-in well, I'd be hard pressed to give it up and would venture into relining it myself, before replacement.
We used to be able to buy that friction fabric for real cheap.
 
clutch

I (and probably others) sell just the buttons, press them out with your thumb, pusn new ones in same way, Mike
 
Augi with super happy time its super insert pads that make happy time :devilish:

Are those clutches as durable as the centrifugal clutches?
 
SlicerDicer said:
Augi with super happy time its super insert pads that make happy time :devilish:

Are those clutches as durable as the centrifugal clutches?

In a word...NO! Because the operator can dump the clutch trying to "peal-out" or slip the hell out of it when the engine bogs. But a manual clutch is more fun.
 
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