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Upgraded clutch springs

Motorhead

CB750 Enthusiast
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Hi all, hope you're all well!

After a lot of miles on it, my clutch started slipping under hard acceleration and it looks like friction plates and springs replacement is due.

I intend to use OEM friction plates, as I always did.

Would you recommend installing stronger clutch springs, like Barnett? Also, EBC say their springs are 7% or something stiffer than OEM.

Opinions?
 
It can help..........one other thing that can help is to remove the OEM riveted double 'cushion' plate and simply replace it with 2 normal steel plates, it gets rid of some of the give that comes from having too much cushion in the clutch OEM. Why if you really slip the clutch for a fast takeoff you feel the clutch lever tight then loose repeatedly, the clutch winding up then unwinding, a spring effect there.

Besides that the riveted plate is well known for coming apart in normal use to spray broken pieces of rivet all over the place.

The clutch on these is sprung at the primary gear, the clutch hub/primary driven gear, and the rivet plate, really too much give there and one reason why the bikes performed crappy in drag testing back in the day, the clutches are simply too unpredictable when loaded hard.
 
Thanks amc49,
Look here, http://www.dynoman.net/engine/clutch/barnett.html

Complete sets from Barnett, with their springs, friction discs, and steel plates albeit only 6 steel plates. They probably assume I keep the OEM double plate.
Maybe I should order the sets and ask for 2 extra steel plates?

All that said, I don't race the bike, just ride it a bit harder occasionally. Mostly (and a lot of) commuting.
Is the double plate THAT prone to disintegrate?
And wouldn't these changes we're talking about compromise anything else? Like cause premature wear of the basket, of the gears or any other components? I thought all this cushioning (and that of the primary shaft damper) is supposed to protect the gears at engagement.
Thanks again
 
Driven normally the springs alone will hurt nothing. The discs may if may like the Barnett ones which use a thinner steel core plate under the friction material, the thinner steel tabs then eat into the basket fingers much quicker than wide tabbed discs do. Asking for extra plates makes that only worse, the extra plates automatically ensure the thinner tabs as you are working with a set clutch distance in there that has to be maintained to work right. Haven't bought Barnett in a while but the 6 plate thing may be them reacting to complaints about basket wear over the years, they could ruin basket in a year or less. You need to run discs that have tabs as wide as the OEM ones.

The stock rivet plate rivets impact at the clutch working and doesn't last forever even on dead stock bikes. seen many with that broken, it being a weak point.

WHAT gear 'protection'?, the clutch ceases to exist in essence at trans gear engagements, how every clutch on the planet works. The gears have to engage with both sides of the drive disconnected, it's the only way they can engage. The gears are otherwise all loaded and running at different surface speeds, the breaking in two of the power train is what allows both sides to change speeds to equalize each other or they never mesh together. What the clutch does, even with all that cushioning missing the clutch itself is a cushion. The primary shaft cushion is as much a harmonic damper for the crank as much as a driveline damper, cranks often break with no damping and these can do it on occasion but usually on the bigger engines.

I forgot the split primary gear which is a cushion as well.

Most of the cushioning is for delicate people complaining about harsh shifting and such, much of the problem being their own technique for doing it. Past that it's NVH issues. (noise, vibration, harmonic)
 
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