2 STROKE WORLD .net

The 2-Stroke Garage => Turning Wrenches => Topic started by: jetta90 on January 18, 2021, 12:57:29 AM

Title: Clutch question
Post by: jetta90 on January 18, 2021, 12:57:29 AM
I've been reading up on the DS7/R5/RD250/RD350 clutch differences.  The write up by SUPERTUNE is fantastic - thank you for all the work and effort on this.

I have a 73 RD250 project that is turning out to be a mix and match affair when it comes to the clutch assembly.  I seem to have the correct later style clutch hub, metal plates, fiber plates, thrust washers, to be able to install the later 7 fiber plate clutch but I do not have a later pressure plate....I have the early clutch plate available only.

Would the clutch work with the old style pressure plate on the newer style clutch hub with the 7 plate set up?
Title: Re: Clutch question
Post by: rded on June 11, 2023, 10:21:17 AM
I have this same question. It seems that the older style p p needs the steel as the last plate to help support the non reinforced p p. I replaced the clutch plates on my R5 and ended up having a friction against the pressure plate. It seems to work fine. I am concerned about the p p failing.

There are thinner steels 1.1mm vs the stock 1.5mm that should allow the spacing to add the final steel plate. My kit from Yambits had 7 friction and 7 steel. but the steels are the 1.5mm.
Title: Re: Clutch question
Post by: m in sc on June 11, 2023, 10:35:00 AM
i wouldn't nec recommend using the older 'not splined' pressure plate, but you can. ive done it.  however, be aware you will need a steel under that 1st which may make the stack height tricky. thinner steels will allow you to def stack more in there.   :twocents:
Title: Re: Clutch question
Post by: rded on June 11, 2023, 10:38:02 AM
Do you know where the thinner steels are available?
Title: Re: Clutch question
Post by: m in sc on June 11, 2023, 10:42:35 AM
banshee ones will work
Title: Re: Clutch question
Post by: rded on June 11, 2023, 10:44:15 AM
:thumbs:
Title: Re: Clutch question
Post by: rded on June 13, 2023, 04:31:48 PM
OK, so I opened up the RH cover again and removed the pressure plate that I had the friction against. I was able to use one of my old steels and it stacked in there. Adjusted the clutch and all good now. So I have the thicker steel on first against the spider gear inner hub and alternating friction steel and ended with the steel.  :righteous:
Title: Re: Clutch question
Post by: m in sc on June 13, 2023, 08:40:07 PM
there you go. ive done that myself.  :olaf:
Title: Re: Clutch question
Post by: SoCal250 on June 14, 2023, 12:48:56 PM
There is a Yamaha Tech Bulletin with info pertinent to this. See number 312 (attached).
Also I have posted quite a bit of clutch info in the Tech Library, including different steels and their thickness.