Hitchcocks Forum

A friend has a Meteor and a Super Meteor and wanted to change the timing chain on the Super. Up till then it ran fine. It has a maggy with a distributor. This has been overhauled by an expert and I have proved it works fine on the bench. Massive consistent spark. I helped Mike fit the chain and we lined up the marks as per the book and checked when the valves opened using a degree wheel on the clutch side. That showed the valves opening and closing at the right time. Mike is familiar with the ignition timing and we proved he had set that correctly. (1/32" before TDC). Now for the problem. It starts with the help of SYB (Start You Bastard) but runs like the proverbial hairy goat and then stops. If we remove one plug lead and start it it runs continuously (bit rough of course on one cylinder) but it does not stop. We do the same with the other cylinder and it runs just the same. But connect them both and it stops. We have done all the obvious, new plugs, leads ok, complete carby swap with his working Meteor, heads off, valves lapped in, barrels off and pistons and rings all ok. I am happy to supply any more details. Any idea what it could be. We both suspect valve timing but the marks all line up. Thanks for reading.

It can't be valve timing if the engine runs in the first place and on one cylinder or the other independently. If the timing marks line up, I am pretty sure the valve timing must be right. The 1/32" BTDC ignition timing is static, not fully advanced, which I would expect to be in the region of 7/16" BTDC, although I don't have any factory data to hand, so I wonder if your ignition timing might be too retarded? The fact it will run and keep going on either cylinder alone, but not together also suggests a fault or weakness in the sparks department, even though you say the magneto has been overhauled. You don't have resistor plugs and / or caps fitted, do you - magnetos don't like either?

Thanks bw The leads are copper and the plugs have no resistor. No resistor in caps either. Also tried 2 new condensers. We also suspected crook fuel so that was emptied out just in case. When lining up the timing lines to point in to each other they are just a smidgen not in line. But if we go one tooth either way they are way out. Does that sound right. The lines are very feint, almost invisible. I'm still thinking ignition timing but we've been very thorough there. The advance weights on the timing side appear to be fine. We're stumped.

Hi Creaky, those timing marks never quite line up perfectly, just close, including the one on the crankshaft sprocket, where it is supposed to point down and line up with a blip in the crankcase casting. It sounds as if you have all that set up ok to me. If anything else springs to mind, I will let you know.

Hi, does it restart immediately ? Vince

I am wondering if it's the fuel? Or fuel tap issue
Sorry if I missed anything about you having used fresh fuel
Cheers Dai

Edit yup you mentioned (spelin) fresh fuel just above

Another edit

I can't helps but think it's fuelling or fuel supply getting just enough for one cylinder but not enough for two

Reading through again could you swap the magneto with one from a running bike?

As has been said it could well be a problem with a weak spark

Only running on one cylinder at a time confusing one that

Vince, It will start immediately but only with SYB spray in the air filter. Sure looks like it's not getting enough fuel.

Dai, It does look like a fuel problem but the tap delivers fuel ok and the tickler works fine. We best do a further check on the needle and seat though.

Dai, No we can't swap with Mike's Meteor (this is a super meteor) as it has a maggy but no distributor. If we could swap we would probably then end up with two bikes that won't start. That's generally what happens when I do swapsies.