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The 2-Stroke Garage => Turning Wrenches => Topic started by: gargantua350 on December 07, 2023, 09:47:50 AM

Title: 7 plate clutch
Post by: gargantua350 on December 07, 2023, 09:47:50 AM
Hello All,

I have an early rd350 motor and I am going to upgrade to 7 plate clutch.  The thrust washer shows 2 different part numbers on the breakout manual.  Is ok to go with either or?  It looks like the 278 part number is the washer with the bevel.  I was able to source a clutch hub and basket and all the steel plates.  I have new friction plates and springs.  Has anybody used the 278 part in a 7 plate clutch upgrade?

thanks

Title: Re: 7 plate clutch
Post by: m in sc on December 07, 2023, 10:06:48 AM
one is a stepped washer with a bigger OD than the other (r5/ very early rd350). IF you have the 3 bolt input retainer on the cases, you need the smaller diameter one or you will hit the bearing retainer. thats what matters the most.


the one i am referring to bolts here (see pic)

this is an early 351 (rd350) set of cases that did NOT have the bearing plate bolted in, nor were the holes tapped for it. I had to tap them in and use a spare plate i had. IF that is there, use the second part number as this one below wont fit if it IS there

 


Title: Re: 7 plate clutch
Post by: gargantua350 on December 08, 2023, 07:42:11 AM
thanks Marc. 

Mine doesn't have the bearing retainer in the cases.  Is the bearing retainer needed?

Title: Re: 7 plate clutch
Post by: m in sc on December 08, 2023, 08:13:02 AM
no, not needed and therefore you can use the stepped washer. I added one but this is going to be a very high strung motor.
Title: Re: 7 plate clutch
Post by: Jspooner on December 08, 2023, 08:05:01 PM
Quote from: gargantua350 on December 07, 2023, 09:47:50 AMHello All,

I have an early rd350 motor and I am going to upgrade to 7 plate clutch.  The thrust washer shows 2 different part numbers on the breakout manual.  Is ok to go with either or?  It looks like the 278 part number is the washer with the bevel.  I was able to source a clutch hub and basket and all the steel plates.  I have new friction plates and springs.  Has anybody used the 278 part in a 7 plate clutch upgrade?

thanks



Do you have the pressure plate and bolts for a 7 plate? Pretty sure you will need those as well.
Title: Re: 7 plate clutch
Post by: gargantua350 on December 09, 2023, 10:08:01 AM
Hi Joe,

Yes I have all the necessary parts including the pressure plate and bolts

thx
Title: Re: 7 plate clutch
Post by: gargantua350 on December 10, 2023, 05:08:16 PM
Hello there,

So it turns outs that I have the wrong pressure plate.  It does not seat all the way down. I bought the clutch assembly thru offer up.  It seems to hit the webs on the inner hub before it seats down all the way.  It looks different from the other late rd350 pressure plates.
Title: Re: 7 plate clutch
Post by: SoCal250 on December 10, 2023, 06:15:45 PM
That plate does look slightly different than RD350 (or even RD400/350LC).
I  see some faint numbers, but have you found any numbers/letters cast into the part? Almost looks like "390"? If I flip the pic 180* it looks like it might be "0G2" but hard to make out. Might just be a prod date code. On many Yamaha parts there's a 3-character alphanumeric code for the model family. That should help determine what it's for.
When you test fit it were the arrows lined up between plate vs hub?
Title: Re: 7 plate clutch
Post by: m in sc on December 10, 2023, 08:12:13 PM
you did try every rotation as well?  bummer if it won't drop
Title: Re: 7 plate clutch
Post by: gargantua350 on December 10, 2023, 10:26:39 PM
Hello again!!

Well I figured out what the problem is.  I done a reverse image search on the pic above and found out it is a pressure plate for a DT400.  It was an honest mistake...I think.  He showed me a DT400 he's restoring and probably got the parts mixed up.  These images were snipped from ebay.
Title: Re: 7 plate clutch
Post by: gargantua350 on December 19, 2023, 11:31:38 AM
Just an update...I found another pressure plate from ebay and now everything went together like it should.  Works great no problems with drag or slippage.  Thanks for the help everyone.
Title: Re: 7 plate clutch
Post by: 85RZwade on December 19, 2023, 03:34:10 PM
This is good news