JHP slipper clutch
 

Is there anyone running a JHP Bucci road and track slipper clutch? what does he charge for them? just sold a mountain bike (now have cash) so am looking at a slipper clutch of some description. STM, or JHP.

http://cgi.ebay.co.uk/ws/eBayISAPI.d...1436 277&rd=1

dont mess about get a pucka factory one ;)

My JHP is now fitted but not been road tested yet. Like the idea of being able to use nice and cheapish ST4 ali plates and any after market type outer basket. Easy to fit also, especialy when you have Jon giving you expert advise "Cheers Jon"
Ask away.
K

Got to agree. These also use standard plates if you want to. An Nick sells these with a full set.

TP and I have them fitted :)

As Mr_S says, you can use the standard plates, ally plates form ST4s etc - well worth it.

Mine is different to the one in the auction though.

Ah yes. TP and I have the 6 post ones. The auctions the later 4 post one which can be used with a locking tool for a starter thingy (looks like a mower with a wheel on, don't know it's proper name)

I think these later ones are made by STM.

The other difference being the 4 poster that I was offered was ramp only, no bearings. The 6 poster is a ramp and bearing setup.

thats why i wont go for it, i want the ball bearing type.

I didn't realise that the new type was not a ramp item.
I have the six post one and it works beautifully, the new ones are supposed to slip even more efficiently. (no bump starting)

Why?

quite a while ago I spoke to a guy at sigma who said the ramp type need regular greasing of the ramps for them to work effectively. He said the bearing type are far better, less greasing, not as harsh in operation.

ah, that will be dear old Neil Spalding .....

Nelly has a brand spanking one in that he'll do a deal on ... STM jobbie ..

Mines got balls !

not what yer missus says ....


Adam, if you really must have a 12 tooth one with balls and ramps then just call Sigma and get your moth eaten wallet out .....

The main difference is the maintanance intervals, a ramp and ball type typically needs a re grease at every 6000 mile service, where as the "pukka" Ducati Course type are designed with a strip check and re grease between meetings or every few hundred miles, with ramp only type being a bit longer, so it all depends on how offten you want to be checking it, if you are a road rider then obviously you dont want to be messing every other weekend or once a month.

Hope this helps Steve and I`ll see you at some circuits no doubt.:sing:

I think you might be confusing centre spring jobbies versus ball and ramp Weeksy.

It's still really only one type - it's just that the later STM Evoluzione ones use a single central (larger) spring rather than a number of individual posts with associated springs.

The idea of the single central spring (STM call it a diaphragm spring) is to allow them to make the engagement of the clutch more progressive and to give better feel. It also reduces the weight of the clutch components.

All of them use ramps to disengage the drive under backwards torque, and some combine the ramps with ball bearings to make this action smoother - note that you would not normally "feel" the ramp action in everyday use (ie, when pulling away or changing gear) as it only kicks in to stop the back wheel locking up.

You've then got various designs of clutch basket, from the stock 12 tooth basket to the STM like 48 tooth basket. This spreads the load of the plates over 48 faces rather than the standard 12, which in effect gives you only a quarter of the wear rate on the basket.

Basket materials also make a difference. Most aftermarket ones are alloy, sometimes hardened or anodized (which is not always the same thing...) and the idea here is to reduce rotating mass of the clutch and help things spin up quicker. The only problem this creates is the mismatch between basket material and clutch plate material can lead to increase wear on the weaker material - ie, an aluminium clutch basket with oem steel plates means more wear in the basket. This is another reason to match the basket material with the clutch plate material, for example the ST alloy plates.

As an aside, I have used both a stock and an early STM 6 post ramp & bearing slipper in the 748. I also have an STM Evoluzione sitting in a box for the last year that I have yet to fit!

There is a marked difference between riding a bike with and without a slipper clutch, in that it gives you so much more confidence to brake deeper into the corners without fear of locking the rear wheel.

It will be interesting to get the STM in the bike and see how that feels on the track, and whether it's a big improvement over the 6 post ramp & bearing one.

Antonye, are you looking to change your user name to Shazaam2?

[Edited on 17-3-2005 by Felix]

he's more likely to change his name to "Sharon" ..... :lol:

Lol - no, just got interested in the topic having started to lock the rear wheel on the road as well as the track, and read a whole load about the different types of clutch and the advantages/disadvantages of both.

It also helps to know what you're up against when you're trying to get the fugging thing off :D

PS. Dibble, I told you that was only at weekends!