OzVMX Forum

Marque Remarks => Yamaha => Topic started by: firko on April 07, 2012, 01:35:05 pm

Title: Yamaha clutch question.
Post by: firko on April 07, 2012, 01:35:05 pm

Even though I've been fiddling around with old Yamahas for way too long I've got a question that's probably dumb but I need to get some opinion on.

I'm about to fit a Barnett Kevlar YZ 250A/B clutch kit to the RT1 clutch destined for the 360 in my Cheney and upon pulling what appears to be a very lightly used RT1 clutch apart find that it's still got the original rubber clutch cushion O rings between the fibre and steel clutch plates. All of the Yamaha clutches I've used over the years haven't had the O ring fitted, in fact, I've never dealt with them before. It seems that most DT1/RT1 punters must have removed them back in the day. My questions are.....

Are there any advantages in leaving the O rings in place with the Barnett (or stock) plates?
Are the O rings only fitted to the street (enduro) versions, presumably to smooth out the operation?
Am I in for a world of worry if I leave 'em out?

An hour later......
I just checked the clutches on my bone stock DT2MX and restored '68 DT1 Enduro and they're identical to the RT1 item except for the lack of rubber O rings. I've been doing these clutches for years but this one having the O rings has got me a bit freaked.
What's the scoop, Yamaha afectionados?

Title: Re: Yamaha clutch question.
Post by: VMX60 on April 07, 2012, 08:25:22 pm

Hi Firko

Good to have you back in the shed

That must be a real early RT1 with the Oring  still fitted

The reason for the oring was to separate the plates to stop the clutch drag when cold using the old motor oil of 1971 sae30 plus a little anti rattle

Leave them out  with the Barnett or std plates

Cheers

Title: Re: Yamaha clutch question.
Post by: pancho on April 08, 2012, 11:08:04 am

 Hi Mark, my RT1 still has the O rings between the plates, it was the first ime I had seen that idea and I liked the look of it so they are still there,
 cheers

Title: Re: Yamaha clutch question.
Post by: Iain Cameron on April 08, 2012, 12:37:40 pm

I still use them in my DTs and RTs

Title: Re: Yamaha clutch question.
Post by: firko on April 08, 2012, 02:06:28 pm

Thanks fellas. The clutch is indeed from a very early yellow stripe RT1 that had been run over by a car when almost new. I bought the engine from the original owner and it's now the engine in the Cheney, original bore and all. I'll sit and think about whether I use the O rings or not in the shed this arvo while I'm doing some fork rebuilding on the Hindall with the footy on the radio and a Easter Bunny delivered chocky egg at hand for a munch.......It's indeed good to be back in the shed. ;D

Title: Re: Yamaha clutch question.
Post by: bazza on April 08, 2012, 02:11:24 pm

Firko sent you test email

Title: Re: Yamaha clutch question.
Post by: Iain Cameron on April 08, 2012, 02:30:30 pm

Have fun in the shed Mark

Title: Re: Yamaha clutch question.
Post by: Freakshow on April 10, 2012, 12:42:54 am

put one on the first plate and another on the last.  put th erest in the box marked spare parts