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Heavy clutch
Trigger1 - 20/10/18 at 08:01 PM

Is it normal to have a heavy clutch on a bike engined car (919 Fisher Fury).

I've only ever driven one other bike engined car and I can't remember if that was heavier than a normal car clutch or not?

Is it normal to have a slightly heavy clutch on a bike engined car, the Fury has uprated clutch springs if that makes a difference?


CosKev3 - 21/10/18 at 09:31 AM

No totally the opposite,bike clutches are usually very light in a car using a foot pedal,as the biker would have just used his hand to pull the clutch in!

With standard bike engine springs in my experience the clutch is way too light in a car with a lack of feel when letting it out,even with uprated springs it improves the feel a lot but it's still way lighter than any car engined clutch.

Any pics of your cable and routing of it?

[Edited on 21/10/18 by CosKev3]


adithorp - 21/10/18 at 04:18 PM

Ive come across a couple like that. It depends on the leverage at the pedal. Get it wrong (ie, cable attachment too far from the fulcrum or too big a master cylinder diameter) and you get a heavy clutch. The other negative effect of that is a very binary bite point; either on or off and nothing between.


Trigger1 - 21/10/18 at 10:26 PM

Thanks both, I'll see if I can get some pics, but sounds like I need someone who knows these better than me to point me in the right direction.


40inches - 22/10/18 at 08:09 AM

You need to get the cable clevis as near to the pedal pivot as possible. I managed to get 100mm of pedal movement to 25mm of clutch lever.


Trigger1 - 22/10/18 at 06:01 PM

quote:
Originally posted by 40inches
You need to get the cable clevis as near to the pedal pivot as possible. I managed to get 100mm of pedal movement to 25mm of clutch lever.


Do you mean this bit?

https://flic.kr/p/2aVXvRe


adithorp - 22/10/18 at 08:11 PM

Yes. From memory (it was 11 years ago) on my Fury I cut the 2 forked bits off the bottom of the clutch pedal and ground it back to flat. Then drilled a new hole through closer to the fulcrum (pivot) and attached with a saddle on the end of the cable.


Trigger1 - 22/10/18 at 09:06 PM

quote:
Originally posted by adithorp
Yes. From memory (it was 11 years ago) on my Fury I cut the 2 forked bits off the bottom of the clutch pedal and ground it back to flat. Then drilled a new hole through closer to the fulcrum (pivot) and attached with a saddle on the end of the cable.


Thanks, makes sense to increase travel, but how does that have an affect of reducing the stiffness of the clutch?


adithorp - 23/10/18 at 07:30 AM

It'll increase the leaverage so the pedal will feel lighter to press and give more control of the bite point.

As well as moving the cables attachment point on the pedal you'll also have to raise the outer cable attachment position in the end of the pedal box to keep it inline.


Trigger1 - 23/10/18 at 04:33 PM

quote:
Originally posted by adithorp
It'll increase the leaverage so the pedal will feel lighter to press and give more control of the bite point.

As well as moving the cables attachment point on the pedal you'll also have to raise the outer cable attachment position in the end of the pedal box to keep it inline.


Now you've explained it, it makes perfect sense, thanks!


AdamR20 - 23/10/18 at 07:49 PM

As above; you want about a 6:1 ratio at the clutch pedal.