Author Topic: Yamaha clutch question.  (Read 1940 times)

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Offline firko

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Yamaha clutch question.
« 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?
'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha

Offline VMX60

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Re: Yamaha clutch question.
« Reply #1 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

Offline pancho

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Re: Yamaha clutch question.
« Reply #2 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
dont follow me i'm probably off line!

Offline Iain Cameron

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Re: Yamaha clutch question.
« Reply #3 on: April 08, 2012, 12:37:40 pm »
I still use them in my DTs and RTs
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline firko

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Re: Yamaha clutch question.
« Reply #4 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
'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha

Offline bazza

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Re: Yamaha clutch question.
« Reply #5 on: April 08, 2012, 02:11:24 pm »
Firko sent you test email
Once you go black  you will never go back - allblacks
Maico - B44 -1976 CR250- 66 Mustang YZF450,RM250
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Offline Iain Cameron

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Re: Yamaha clutch question.
« Reply #6 on: April 08, 2012, 02:30:30 pm »
Have fun in the shed Mark
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline Freakshow

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Re: Yamaha clutch question.
« Reply #7 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
74 Yamaha YZ's - 75 Yamaha YZ's
74 Yamaha  flattracker's
70  Jawa 2 valve speedway's

For sale -  PRE 75 Yamaha MX stuff, frame, motors and parts also some YAM DT1,2,A and Suzi TS bikes and stuff