jimc wrote:
I think you can judge the value for money by the way they push Malossi Kevlar Belts in their mis-translated blurb. Well don't buy them just because you think you are now getting a Kevlar belt - the Piaggio OEM belts are all very high quality Kevlar belts in their own right, and received wisdom over the years from both owners and dealers is that they usually last longer than any third-party ones.
Back to the clutch bits. The clutch, driven-pulley spring and spiral all need to be matched to the variator, so if using one of these perhaps one would want to add a Malossi variator. Hmm... There have been numerous threads on MV with stories of the Malossi rollers becoming mis-shapen well before one would expect the OEM ones to.
I can say that their performance parts provide huge fun for youngsters on their 50cc scooters, and keep dealers provided with a steady succession of broken bikes to mend.
Back to the strangled sea-lion. This occurs when the clutch bell and shoes have become somewhat glazed (as they all do with time) and the bike is ridden in slow-moving traffic for a while. The clutch will be slipping to some extent, especially if some rear brake is applied at the same time for full control at very slow speeds. The clutch heats up and its biting point becomes erratic. This can produce judder and squealing. It is more often found on heavier scooters or those with heavier riders.
Slow speed control may be more problematic with a clutch that has a more positive and immediate biting point (Malossi?), as they are designed for a fast take-off every time (e.g. on the track), not limping along in congested traffic. IMHO the best way to reduce clutch judder and noise is to change the variator end first. Either some slightly lighter weights, or Dr Pulley sliders, or perhaps the J Costa.
Just musings - feel free to tear to bits.
It seems that once your clutch bell has got the glazing, even if you attempt to remedy the problem, you should just resign yourself to the fact that the Sealion is here to stay.
The Dr Pulley HiT clutch and Clutch Bell (which has better ventilation slots which keep temps as low as possible) seem to be the way to go. I believe larry8 has some experience with them.
I think the sudden appearance of the Sealion on my bike (installed at 5000KM - now 6800 on the odo), is directly related to putting 13gm Dr Pulley sliders in the variator.
While the take-off is improved with the heavier weights, the engine revs higher for longer when you take off. Particularly when you are carrying a pillion. Add this extra revving up over 1000KM, and you would be getting significantly more friction heat generated than if you were using the OEM 11.5 roller weights.
So to balance out the equation, I think installing the Dr Pulley HiT clutch would equalise the friction by not letting the clutch spin so much during the initial revving phase of takeoff. The clutch would bite in harder to the bell, therefore reducing the spin and subsequent friction heat.
That's my theory anyhow.
Of course, loosing a bit of rider/pillion weight wouldn't hurt either JimC