I didn't build my Fury I bought it ready built (was factory built but the first owner paid - not me!). Was sold as having a "R1 clutch with heavy duty springs" or similar which I took to mean a Barnett conversion as the 5PW has a diaphragm clutch as standard.

Its just starting to slip at the moment when doing full throttle clutches gear changes.

Popped the cover off expecting to find worn plates (new Yamaha plates at the ready) but to my surprise its running a completely standard clutch.

Measured the plates and they're not really showing any wear at between 2.95 and 3mm (the new - admittedly dry - plates I have measure 3mm!).

So guess its time for more clamping.

Options:

1) double up the diaphragm springs. Pro's: cheap (I already have a spare one), Con's: poor feel? Not as effective as a barnett conversion?

2) barnett conversion, Pro's: should solve the problem and give good feel, Con's: £115 (anyone know anywhere cheaper?), confusion over which springs to use (washers?).

3) AB Performance billet clutch - TBH I don't know much about this - is Mr Bates reading this? Or someone else who's got one?


Your thoughts experiences please gents before I press "BUY" on a Barnett clutch

Suppose I could just give the double diaphragm a go and see how I get on as I already have the bits. Then buy something else if doesn't work well or to my taste.

I have doubled up the diaphragm spring on mine. It does give more resistance to the clutch pedal, and slightly less feel but I had pretty much got used to it the last time I drove my car.

Before I fitted it the clutch was slipping from third upwards and the plates were within tolerance.

You should try the diaphragm spring anyway I think - shouldn't take more than 15 mins to put it in.

James

[Edited on 20/11/09 by james h]

Just a thought...........

Are sure it is slip and not wheelspin. I took my car round the block a couple of weeks back and was lighting the tyres up in the dry in 3rd until I got a bit of heat into them.

- Jim

Jim - valid point and I know what you mean this time of year but this was a couple of months ago with tyres up to temp and even shifts from say 4th to 5th.

I'd change gear and the revs would stay where they were for a moment before dropping down - felt like classic clutch slip to me. It was confusing the gear indicator as well - its wouldn't show the next gear selected until the slip stopped - which makes perfect sense as it compares road speed to rpm.

It is a little strange as the plates have plenty of meat. I guess as I'm getting used to the flat shift on track I'm giving it more and more welly. And a flat shift at high revs is probably quite heavy on the clutch.

I'm hoping its just a clamping force issue unless the plates can degrade without loosing much material?

I was planning on getting rid of the anti-judder as per Paul Rogers' suggestion.

To be honest I didn't realise that the standard diaphragm clutch could take this amount of abuse in a BEC.

[Edited on 20/11/09 by hobbsy]

I am pretty sure its not a degradation issue - there was loads of clutch slip before, then none whatsoever after adding the extra spring. I guess clutch slip is a factor of the car's weight and acceleration, weight obviously being much greater in BECs than bikes

Try 1)

If it doesn't do the job for you go 2)

3) is a non-starter as Andy himself fits 2) to R1 based cars - that in itself tells you what the best option is :-)

- Paul

I have a 5PW

I've used the 2 diaphragms with sucess booth on street and on track.

After completly trashing the clutch (actually it was way more bad driving than anything else, leading to plates breaking inside the clutch basket!) I went to a Barnett spring conversion (+ stock plates), as my intention is turboing.

If I were you, I'd go to double diaphragm.

Joao

I have a 5pw with double diaphragms no problems after about 1k miles

valid point on the wheel spin side of things I get lots of spins in 1,2 and 3

cheers

paul

im just running with 1 spring at the moment and have done over 3000 hard miles and no slip yet, but i would go for the 2nd spring then after that get some new yamaha clutch plates/steels
as someone else has said its a quick job so just give it a go and see

If your going just for double diaphragm springs would you fit longer bolts and is that it job done?

I don't think you need to bother with longer bolts as its not adding very much thickness and there is plenty of thread.

No need for longer bolts.
It's a 15 minute job.

2003 R1 5PW in mine.

Just about to finish fitting Barnett clutch converstion (courtesy of AP), gotta be the best way?!