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Twinshock Clutch Plates Query...

Featured Replies

The Frontera uses different plates from the Sherpa, they are thinner which is why there are more

 

Be careful how much you back the nuts off as they run very close to the inside of the casing and can catch when the motor is running, even if they appear to have clearance when setting up. I reduce the depth of the adjuster nuts on my bikes to about half their original depth so that there is no issue with clearance when backing them off

 

good tip woody, do you still wire them?

No, never have.  I know others will have a different opinion from this but I've never had one come undone

  • 2 months later...
  • 8 months later...
  • Author

To return to this rather old topic...

 

In the end I used friction plates from some sort of generic Jap 125 and they worked a treat (though I did gave to file down the tangs a bit to fit the basket).

 

Problem is, I now also own a 350 Sherpa trials outfit with a slipping clutch and am considering the same mod but... Can't remember which Jap 125 plates I used.

 

Anyone got any idea?

Don't know that one, but do know that Honda CR125/MT125 friction plates fit into Montesa Cota 348 clutch baskets, if you remove every second tang

The plates you need were used on lots of different Japanese bikes eg. 98 - 01 KX80, Honda VF500C and VF500F, 86 - 94 CBR250RR, CRF150, XL200, 81 - 82 CR125, CB125, 01 - 15 KX85 and many others. You just need to file the lugs a little narrower. I like the CBR250R version best as it has a bigger ID and a narrower contact ring - less drag, more grip with the same or less spring pressure.

 

There's a commonly held belief that Type F ATF is the best oil to use in a Bul clutch. My testing showed it was no better than any other ATF, and all of the ATFs gave less holding capacity than a non-friction-modified engine oil. The best I tested was Castrol Power 1 4T 5w-40.

Edited by oldjohnno

  • 6 months later...

I've noticed these plates are listed as 110mm dia but the hub measures right at 110mm inside dia.  these plates will fit in the bultaco drum?(after filling the tabs)

10 hours ago, bgeacook said:

I've noticed these plates are listed as 110mm dia but the hub measures right at 110mm inside dia.  these plates will fit in the bultaco drum?(after filling the tabs)

Which plates are you talking about?

the Japanese bike plates (kx80, vf500, etc) that user oldjohnno lists

 

 

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