Grabby Clutch

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tony.mon
Posts: 16022
Joined: Wed Jul 25, 2007 10:46 pm
Location: Norf Kent

Grabby Clutch

Post by tony.mon »

It's always had a grabby clutch, and although in practice you can ride round it by dropping the clutch early and using the torque I'd rather be able to slip the clutch and keep the revs up without it locking up unexpectedly with a huge inadvertant wheelie.

So I wondered why Storms often do this?

I've got a theory- i think it might be because the holes in teh master cylinder or at the clutch pushrod end are small and so when you dump the clutch to the bite point, intending to hold the bite point and match revs to it, the clutch cannot feed out as quickly as you move the lever.

This means that you feed the lever out and hold it, but then as the fluid flows through a fraction of a second later it seems to let more clutch out than you think you've got dialed in. Does this make sense?

In order to fix this I want to try a different master cylinder or lower cylinder. Top one should be easy- just swap for any other bike's cylinder and lever, but has anyone tried it?
It's not falling off, it's an upgrade opportunity.
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clayderman
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Location: Surrey

Post by clayderman »

I can't say I have an issue with mine but have you looked at the clutch actuating rod behind your front sprocket cover and cleaned out all the gunk?
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Stratman
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Post by Stratman »

It isn't a common problem or characteristic, so I would also suggest cleaning the rod etc and perhaps bleeding through with fresh fluid too.
Two bikes, still only four cylinders!

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Stormin Ben
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Location: Birmingham

Post by Stormin Ben »

Tony,

The clutch woes are caused by two things

1. Main cause -clutch springs made of knicker elastic
I fitted a set of EBC ones (£8 from Demon Tweaks) and mine was 100% better

2. Notches on clutch basket
Where the clutch plates engage on the basket they can cause slight dips in the teeth. This then means they dont slide along it smoothly.
While I was fitting the springs I filed them gently


Ben
I've got an inferiority complex
But its not a very good one!
tony.mon
Posts: 16022
Joined: Wed Jul 25, 2007 10:46 pm
Location: Norf Kent

Post by tony.mon »

MMMmmm. Might just be the way i dump the clutch to the bite pint when taking off hard.
Seems like the clutch takeas about 1/2 a second to finish feding the lever movement in, so just when I'm balancing the revs by holding the clutch in a bit while opening the twistgrip it locks solid and laaaarge wheelies result.

So to find out for sure I bought a low-mileage secondhand clutch, fitted it yesterday and it seems lots better.

But I'm off to the Bulldog Bash on Thursday and will run it up the dragstrip to make sure. :twisted:

If it still does it, then all that's left is the bores in the mechanisms in the hydraulic clutch not being able to flow the fluid quick enough to keep up with me.

If that seems likely, I'll replace one bit at a time to see where the problem is and report back on this forum.


Thanks for your comments, though.
It's not falling off, it's an upgrade opportunity.
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