slipping belt drive

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Hi there I have fitted a belt drive kit to my 1957 99 dominator(I know this forum is for commandos) but I'm sure problem would be the same ,After about a 5 mile ride if I accellerate hard clutch slips ,not just a slow increase in revs but it lets go completley,if i slow down then take off again alls fine I'm sure push rod is adjusted correctly IE 1 turn out, could I have a problem with my spring plate? any help appreciated
 
Check that belt can be twisted fairly easy to 90' as it get as tensed as a chain once everything ride heated. Might be tugging on basket alignment. That's about all that different from chain in what causes clutch slip, except the belt is best run dry for the clutch benefit. I've had TS main shaft nut back off for weird engagement and slipping.
 
I would take off the primary outer cover and check that the clutch nut is secure and the rotor nut too. If the belt is too loose it could slip as Hobot says. If oil comes out when you remove cover you have worrys too. Pop the cover and let us know.
 
NO NO NO, you can not run a belt too loose unless its just flopping loose to even stay on at rest. Belts work fine loose as a goose otherwise. Look it up if don't believe me. My post was warning not to get it TOO Tight when cold. Clutch slip has nothing to do with the belt itself, just same ole stuff us chain gang deal with too routinely.
 
Hehe, my 1st ever sense of clutch slip was on my 1st Combat, entering hwy steep with blinds each side so staying on good throttle to snick 2nd and heard chirps and hesitation in acceleration, finally realized it was tire spin not clutch at all. Second time was '74 850 in 3rd, which was the grimed plates. Third time was pre-Peel Combat with main shaft TS nut backing off. Forth time was the cable end lever slipping off ball pivot after a cable change. Fifth time clutch issue was the bolt/nut adjuster backing out then off. Sixth time with clutch issue was the center nut losing grip after chewing into the soft lock tab I've since tossed in a bin.

If belt too lose in Nortons what happens is it flops-rubs against the case bosses so obvious excess particles accumulates there then piles excess in bottom. If clutch not stable so belt rolls off, almost all of it will be found behind the crank pulley and in the alternator spaces : (

If clutch shaft not stable or grit gets in so front pulley side plates rubbed on significantly, belt edges fray apart fast so remains almost all compacted behind pulley and alternator spaces : (
 
I haven't seen a Dommi belt drive kit, but i would recheck clutch set up, is the cable the correct length - is there some slack in the cable at rest etc.
And check that the belt is loose enough - things get hot very quickly if there is too much tension.
If clearances are set a bit tight these clutches can start slipping when things warm up - i have one doing that at the moment due to temporarily running a cable scavenged off another bike and having no play at the lever.
5 miles is not very far though so it should be something obvious.
 
Hi there thanks for replies,I probably should have said slipping clutch not slipping belt drive as I'm sure belt is not slipping it must be clutch,I have since checked everything and found the following belt has 30mm of play up and down(as in instillation instructions suppied) Drive pully is on a keyway so that can't slip,clutch basket has lock tab still in place so that hasn't slipped and clutch cable has freeplay before clutch engauges so that leads me back to either plates slipping,but these look in good condition,to rule these out I cleaned with brake cleaner,and made sure they were placed in the correct sequence,only other thing I can think of is pressure plate hasn't got enough tension,I happen to have another here so will swap and try that. anyway if anyone has any more suggestions please reply. ps good to hear from another KIWI thanks Ian
 
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