I am probably going to replace steel drive plates and friction plates.   Not sure about the rubber cushions yet if they are even needed, but the lil guy shifts 
so smooth since I rebuilt the trans I almost want to replace those too.  

Was looking at Barnett for now.   

update: Barnett has discontinued the plates and it appears partzilla does have them in stock.  $285

Pabdt, unless the steel plates are really warped I personally would not replace them. I would keep the rubber cushions.

Im running this china clutch in my ct3. 150 miles so far. im not running the cushions for now and just hit he steels with some scotchbrite.

5pcs Clutch Friction Disc Set For Yamaha AS2 AT1 CS3 CT1 DT100 HS1 LT2 MX175 YA6 | eBay

I'm still using original from 1970 haha. Cover never been off.

DVM, when I got this bike, the orig engine was in a box with 2 other clutches, so plates are gone. However, I do like those weighted plates. My DT125A is smooth as glass w/them.

I think I may experiment by adding another drive plate (if it fits) to tighten stack or a washer to shim the flywheel bolts possibly both unless the friction plates are worn/poor shape.

84PRERUNNER, thanks for the reference.

RT325,that’s impressive—50+ years and still untouched! at this point, opening it would feel less like routine maintenance and more like an archaeological excavation.

All 177.60cc of engine and an apparent good tune have put the clutch setup on notice. I'll report back on the repairs.

NEXT UP, I SAY AGAIN, NEXT UP!

Going to buy an EXTRA pipe and modify it w/the cone. DVM, did I not see you once post a how to? I'm guessing, remove rear baffles, add cone over silencer pipe? Tack weld for testing.  I can't find the instructs online.  I think this particular bike is a good subject because it runs well, so just a matter of testing the pipe, checking plug.

PABDT,
If you are planning to to put a cone into a CT remove the spark arrestor, make an opening in the rear of the pipe, remove the two baffel plates. Make a cone that will fit correctly as far back in the pipe as you can. I brazed the cone in place and then welded the cover back in place. When I first did this on my CT3 I cut way too large (from the rear toward the front). On later CT pipes I made the opening just large enough to place the cone in and have working space to braze the cone in place.
I sent my complete write up with photos to this site quite a while back. I thought it was posted somewhere.

yamaha-enduros.com/index.php/forums/perf...inning-by-dvm#168340
 

About 4 years ago when I got my CT1 going, I put in cheap eBay friction plates, and they always slipped. The springs were just slightly under spec, so I got new stock springs, but they still slipped. A year or so ago I finally got some OEM friction plates, and they happened to be on sale for $11 each. I also buffed the steel plates with 320 grit sandpaper, and it's been working beautifully ever since. I can't even make it slip.

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