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What heavy duty clutch springs for turbo ZX9r enigne?
dave_424 - 13/5/13 at 11:23 PM

Hi, I am trying to figure out what clutch springs to put in my ZX9 as I am building it. I can get the 10% heaver EBC springs, or barnett springs that don't say how much heavier they are, price is around the same.

What are your thoughts?

imp paul - 14/5/13 at 05:49 AM

hi i would look at muzzy, or ape racing, or Ryan schnitz racing, but also think of the clutch basket and fit genuine plates

mark chandler - 14/5/13 at 10:35 AM

When I stuck a turbo on my blade engine HD springs were not enough, you need to look for lockup clutches

dave_424 - 14/5/13 at 11:06 AM

Since this engine is powering a sub 400kg RWD buggy off road, I get monumental amounts of wheel spin as is, so that isn't really the issue, I am just thinking when I have the buggy on the dyno I don't really want clutch slip to ruin the mapping.

I doubt I will be going lockup due to the massive price, unless I machine one myself....

mark chandler - 14/5/13 at 11:21 AM

My blade with HD springs slipped once I got over 175bhp, the car span the wheels but once you get up the gears started spinning the clutch instead which if you blue the plates and do the driven plates in will cost a fair bit, if you can make yourself they do not look that clever so would be a DIY proposition.

I would suggest a lathe which you can index the holes be a good start

imp paul - 14/5/13 at 12:46 PM

quote:
Originally posted by mark chandler
When I stuck a turbo on my blade engine HD springs were not enough, you need to look for lockup clutches



im with mark on this, its a must need part for turbo bike engine, or it looks like you will have a big stack of dead plates lol

dave_424 - 14/5/13 at 01:05 PM

I think I will go with HD springs and get it mapped to as much as the clutch will take, then look into a lockup.

imp paul - 14/5/13 at 01:45 PM

O well we did tell you so, bang goes the clutch basket, and then it will murder the motor. enjoy the rebuilds
power costs money how fast do you want to go today

dave_424 - 14/5/13 at 02:09 PM

People out there on turbo zx9's run a mix of OEM and muzzy clutch plates and muzzy springs, 15psi street and 25psi race with no clutch slip.

Someone also runs a stock motor zx9 just with forged pistons, makes over 300whp with stock trans, stock clutch just hard springs.

I know it is very different trying to push a bike than a car, but it can't be that bad. I have no clutch slip at the moment, it would probably slip with an extra 20-30hp, so a set of HD springs should see me safe up to a reasonable amount of power. Not all clutches are made equal.

I can band my clutch basket if there is a chance of failure there. One thing with lockups on the ZX9 clutch is that it will break clutch pullers constantly

Just asking what springs out there are the strongest??

twybrow - 14/5/13 at 02:51 PM

If you want more spring than the 10%, then just add washers to preload the springs more....

imp paul - 14/5/13 at 03:52 PM

Ok so if your doing it home brew locost put a band on the basket and some small drill holes to let oil pass in basket is common with ape springs see how it goes