Hitchcocks Forum

My 2005 Bullet Sixty-5 has a habit of stalling while idling - usually just as the lights go green! It has a high level trials exhaust with baffle tube and a VM28 Mikarb with a pancake air filter, 2.5 slide, 125 main jet, P2 needle on middle slot and 30 pilot jet. The carb to head rubber is new. The plug is NGK B8ES gapped to 20 thou and the coil and HT lead are new. It also has a Boyer ignition with the idle timing set using a strobe. I have stripped and cleaned the carb and tried setting the idle as per the recommended procedure, but adjusting the idle jet has very little effect. Sometimes it will idle for ages and other times not, the stalling being random. It also seems worse when the engine is cold. Is it possible I have the wrong jet/needle set up or is there anything else I might have missed ?
All suggestions welcome
Many thanks

Easy to do: Have you tried a BRAND NEW... ie not just cleaned-up spark plug?
It's worked for me in the past on Enfields and H*^das as well.

If the motor does not respond to idle air screw adjustment, odds are that the jet is obstructed, OR the jet is not the size correct?


The float level also has an effect on idle adjustment; 28mm.


No mention of uneven idle, or slow return to idle, so the presumption is that the pilot jet is too large. (30 is a large jet)


Pilot air-screw two or more turns out and an adjustment 'dead zone' of +/- 1 turn? Fit a smaller pilot jet.


Make sure that the choke is seating fully, and that the rubber seal around the choke shaft is in place.

My 2000 Bullet always stalled when the lights turned green, my theory is green lights suck electricity from the engine.

My 535 is timed with strobe light at just over half throttle at fully advanced std is 32deg btdc I set to 26btdc bigger carb 8.5 piston. I use boyer ign but if batt voltage is down a wee bit (mk3) system advances I would try a 27.5 pilot and try your timing on fully advanced, you can fine tune on road moving the back plate in dist if it pinks.

Many thanks for the above. I will check the float level and try a 27.5 pilot jet

If you manage to completely cure it Klutz, tell us how. Every Bullet I've know, British or Indian, has or had the habit of cutting out at the lights! I've always put it down to a quirk of big singles.

I think a lot of problems are caused by having the idle set too low to get the nice slow thumping idle open the throttle as the clutch comes in and stop, get it revving a bit before moveing.

Scotty makes a good point. It sounds nice to pull away at low revs on a big single but there's not a lot of torque at low revs. It's not a steam engine!

I'm sure he knows how to set off! I think it's the random stalling at tickover which means keeping the throttle blipping, just in case. Setting a high tickover has never cured it form me, even my old Yamaha SRX600 used to do it sometimes, and that was a right bugger to start again when surrounded by lorries!