Hi, my hyper has a JHP slipper clutch fitted and when I pull away from neutral to first there is a horrible jerky noise and quite often the bike stalls. When the bike is stone cold this doesnt happen. The millage of the clutch is just over 4000 miles, any idea whats wrong?
Is it when you select first at a standstill? Sounds like the clutch is dragging. Try it with the clutch lever at maximum span. If that improves things, bleed the clutch and go from there.
When I pull the clutch lever in it disengages fine. I bleed the clutch last week. Just from neutral to 1st when you have to slip the clutch it jerks as it slips and I end up stalling
My slipper clutch is very jerky as well, it is supposed to be a DP item although I somehow doubt it. I think it is just the nature of the beast with some of these clutches. Using alloy plates instead of steel makes a difference and also setting the stack height to spot on can help. I also have a Sigma slipper clutch on another bike and that is mostly fine but the design is slightly different.
I have a STM slipper on my 748 and that makes a right noise and vibration when making a spirited get away, if I drop the revs it is much better, I do strip and grease the ramps around ever 500 miles and that makes the overall operations much quieter. Steve
You may want to check your dished steel plates as they could have deformed and not be dished any more!
tried searching the for instructions for servicing the jhp slipper clutch but cant find anything. Does anyone have any to show how it comes apart, what points need greasing and stack height ,plate order etc thanks.
is it a six spring bobbie......if so remove the 6 screws and the springs then remove the pressure plate this may well bring the push rod out with it thats fine. before you take any plates out measure how far below the edge of the inner drum the final plate is..........then come back to us.
yes its a 6 spring bobbie. Measured with a verynear and the distance from the plates and the inner drum is 5mm, the distance to the outside drum is 3.5mm
so that distance to the inner drum you could get down to 4 mm by changing a couple of plates 1.5 to 2mm = the 1mm to get it down to 4mm. have all the plates out now but keep them in the order they are in you can check what you have got and check the dished plates they are the ones with the dimple on one side. if all your plates are now 2mm your friction plates are worn out.....if they dont look to bad you could change some of them to assist getting the measurement down to 4mm this will bide you over....
dont forget when you are putting them back in to put a friction in first........not a steel or it will go messy!
dont forget it is working hard above and beyond just in and out with the lever........it depends how hard its been used, how many times it has been readjusted, what quality the clutch pack is and so on........\ tell me how many 2mms and how many 1.5mm it has when you get it apart..........
So in theory the frictions are in good condition dont you have a magnet on a stick that does the trick.....
right got the plates out all the steel plates have a notch in them but none looked dished. What should be the correct stack hight be? Just phoned jhp Coventry up but the spare department is shut till Monday.
not notched........there is a dimple, looks like a dot punch mark on the working face if its a spring plate... If your measurement was correct at 5mm below the edge of the inner drum you need to replace two 1.5mm steels with 2 2mm steels that will give the pack 1mm extra height when you rebuild the plates in to the clutch so that measurement you took is now 4mm....
