Hitchcocks Forum

Good evening once more one and all, This is not a new problem, just one I've got used to and think it's about time to deal with. 05 Bullet 500 starts 1st kick from cold (assuming I don't lose focus), runs fine, starts 2nd kick from warm (with luck). But is very nervous about settling down to tickover if for example stopping at a junction/traffic lights. Typically she will tickover for a few seconds and then stall. I generally resort to blipping the throttle in stop/start traffic situations. I've lost count of the times I've set up the slow running in the workshop with a warm engine, only to go out for a spin and find she stalls at the first road junction. Could it be a partially blocked pilot jet?
Thanks in advance for any light thrown on the subject, Wilf.

Hi Wilf,
Had the very same problem on my 02 500 bullet, turned out to be a partially blocked fuel tap, this allows the bike to perform normally in every way except it wont tickover reliably. the plastic pipe that goes up into the tank gets broken at the base. Well worth a look before you disturb carb etc. Check fuel delivery system.
Hope this helps,
Regards Chris

Carburetor float height too low?

Yes.


Is the rubber seal around the choke shaft seated correctly, and is the choke fully closing/seating?



If attempts are correctly setting the air screw does not give you the result you seek, try setting it incorrectly to see which way makes the problem worse?


Try the Air screw 2 turns out, then only 1? Still no change? 3 turns v's half...

Hi Wilf, It might also be worth checking the bob weights and springs in the ATU, behind the points back plate in the distributor, assuming you are still using points and also check the cam is advancing and retarding smoothly, as wear and / or slop in this mechanism could cause the symptoms you describe. Cheers, Paul.

Its a long list of possible causes and could be all of the above, process of elimination i think..

Whether you still have the pulse air valve fitted or not, just check the blanking screw or plug in the carb inlet manifold.

If system still operational then check for split tubes and connections looking for vacuum/air leak which may well weaken the mixture at tickover..

Drained the petrol tank this evening and had a look at the plastic feeder tube cum filter, which was in good condition. The five litres of petrol took an age to drain and had a lot of air bubbles in it. About a quarter of an inch long, and one every inch or less. Curious. There was a very small amount of what looked like black iron filings, Perhaps a quarter of a mustard spoon, so I filtered the fuel back into the tank via a coffee filter. (Should be dried out by the morning, HaHa!) Started her up and found the pilot air screw a bit more responsive, though no cure as yet. Ticks over nicely for about ten seconds then dies. I checked the rubber on the choke plunger, and all OK. Points cam is working smoothly but yet to check auto advance weights. Bike is fitted with Eureka ignition by the way. I shall work my way through your other suggestions chaps, and report back over the next few days.
Thanks for all the helpful suggestions. Wilf.

It's a long shot but have you tried testing the fuel flow through the tap with the tank filler cap open? The air bubbles you mention remind me of the problem I had a few years back with a blocked filler cap vent, though my bike was just cutting out completely when riding at normal speed, nothing like your problem. (Don't ask me where the vent is - no one could tell me and I ended up drilling a small hole in the outer layer of my filler cap.) Might be worth a try just starting it and seeing if it will tick over with the fuel cap open. No smoking. And I wouldn't smoke while drinking this morning's filter coffee either...

Don't think it's that Geoff, I tried opening the filler cap whilst draining the tank. Made no difference to the bubbles or flow rate. Good thinking though. Cheers.

Oh well worth a try. Strip and clean carb next gets my vote then.