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Ossa Mar Clutch

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Hi All

I have a 250 MAR 1976 mk3, I have purchased a clutch for it (Surflex part number S1202)

The clutch in the bike (and one I also have from another 1976 mar) has one thick steel plate, Five friction plates, four thin steel plates and the pressure plate has a plate attached to it.Also all the steel plate working faces are dimpled to allow the oil to flow (I guess!)

The set supplied has Five friction plates and Six plain "undimpled" steel plates.

Looking at manuals I can find slightly earlier engines did use Six undimpled steel plates (one is thicker mind you) with the last steel plate going in last. And I recon the pressure plate does not have a plate attached to it, Can anyone confirm this?

I have also found a gripper manual and this looks like what I have, Can anyone confirm this?

Surflex do market another OSSA clutch (S1203) but can find no technical or even which machine this or the S1202 is for. My feeling is that the S1202 is for earlier bikes and S1203 for 1975/76 on, Again can anyone confirm this?

I have contacted the dealer who supplied the clutch and he was very sympathetic and said he will help if necessary but explained that he has found very difficult dealing with Surflex in the past as he has to go through another company and a translator etc (surflex are Italian BTW). The dealer is also OK with me asking you guys for advice and input which may help others with similar issues.

After all that I may just fit the friction plates (which are all the same as far as I can tell) as they are the parts that are worn! However I would still be Interested in information from people with more OSSA experience than me.

I think you have been sent a set of gripper plates, the later bikes (grippers) and the mxers had six plates fitted. Try Barnett kevlar plates and springs from Rex Caunt Racing. :D

Never knew Rex Caunt did Barnett plates, they aren't mentioned on his website. I bought Barnett friction plates from the States and although I've only tried the bike once, as I then broke it, the difference with the clutch was impressive. I used original steel plates and springs with the Barnett frictions and putting it into gear you'd have thought that there was no chain on the bike, no clunk or anything, perfect disengagement. When riding, same result, immediate disengagement whereas previously it may have disengaged by the time the next trial came along....

As far as I know all MAR models and Gripper have 5 steel/friction plates but it's been a while since I've been into a Gripper engine so can't be sure. I've also got a distant recollection that the motocross drive plates are alloy, or is that the Bultaco - can't remember. Again, as far as I know the pressure plate acts as a 6th steel plate as it is next to the last friction plate. The inside steel plate is the thickest.

Hi Woody,

Sorry for the confusion Rex Caunt only does the springs, Igot my Barnetts from the USA,as you did.

Regards

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