Author Topic: F model clutch springs  (Read 220 times)

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Offline Afterdarkmark

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F model clutch springs
« on: March 09, 2019, 04:53:57 AM »
My 79 RD400 has a very heavy clutch action compared to the 77 model I owned until recently. I typically use just two fingers for clutch since my motocross days but this clutch gets pretty tiring after a while.

I have no idea if the springs are original equipment. The bike has been raced at some point in the past, so I assumed they were some kind of heavy duty springs the previous owner had installed. I recently replaced them with an EBC spring kit I bought on Ebay, but those were just as stiff (slightly stiffer actually). The clutch lever, cable, and clutch cam all move freely with little resistance when I remove the left engine cover i.e. disconnected from the clutch itself.

Was it normal for the 79 to have a heavier action than the older models?
Maybe I need to find some original Yam springs.

Offline mervin

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Re: F model clutch springs
« Reply #1 on: March 09, 2019, 07:04:08 AM »
Check the worm drive is not dry or worn . I had the same on my D changed springs still heavy. Changed worm drive for a new one and it was much better.  Also make sure the lever on it is as near to 90 degrees to the cable as possible. If the lever is to low an angle it can do that to

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Offline betty foRD

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Re: F model clutch springs
« Reply #2 on: March 09, 2019, 01:47:58 PM »
Probably the worm like Merv said but always worth checking the ‘obvious’ , ie the cable itself. Might seem free when no tension but easy for them to get dry or generally fecked !

« Last Edit: March 10, 2019, 06:57:27 AM by betty foRD »
Rev 'em till they rattle

Offline Afterdarkmark

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Re: F model clutch springs
« Reply #3 on: March 10, 2019, 03:04:02 AM »
Thanks for the advice, I'll check it out.

Online 5port

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Re: F model clutch springs
« Reply #4 on: March 10, 2019, 11:15:43 AM »
Mate, the standard Yamaha clutch springs should be good.  They are the same throughout the RD250/400 and 70's TZ250/350!  No need for heavy clutch springs if clutch in good condition and you use the MA2 wet clutch compatible gbox oil.  Agree, worn actuator can be a problem.  Cheers

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