Have a look at the choke, At the end there is a rubber disc that blocks the hole off, See if it looks good.
Cheers Bill.
Cheers Bill.
E: Engine Egli 500 Special Carburation
- Thread starter Ben Langton
- Start date
Have you checked your compession ratio? Nothing is more able to prevent a pleasant start and ride than a high ratio it wasn't just poor petrol that kept new Vincent's in the sevens. While I was taking the bikes to Cadwell for VOC races I needed relatively high ratio I say relatively because often we had to still bump start but if you are not racing and opportunities to give it stick are vanishingly small what is 10:1 or 9:1 for?
I wonder if he has one of those squishy things for a piston, Not for me !.
Have a look down the plug hole Ben. Cheers Bill.
Have a look down the plug hole Ben. Cheers Bill.
Ok, had a minute to pop back in the garage to check a few things.
Fuel tank, taps and lines are clean and work as they should (the first thing I did was to clean that out when I got it)
Checked the choke, rubber at base looks fine. However I will hold my hands up and say I have not been putting the choke correctly on, ie up in the locked verticals position which is proberbly why I have needed to cover the velocity stack to start, could this be the problem? I doubt it as the next thing I checked is the coils.
I have the BTH red label which I understood was a very good type? And do have two coils, see pics. Slide pic too.
I'm still thinking the bike was built and run very few times if at all, it seems to have the "right" bits but maybe was never dialled in correctly then again it was on the road and I had heard it had been hill climbed???
Fuel tank, taps and lines are clean and work as they should (the first thing I did was to clean that out when I got it)
Checked the choke, rubber at base looks fine. However I will hold my hands up and say I have not been putting the choke correctly on, ie up in the locked verticals position which is proberbly why I have needed to cover the velocity stack to start, could this be the problem? I doubt it as the next thing I checked is the coils.
I have the BTH red label which I understood was a very good type? And do have two coils, see pics. Slide pic too.
I'm still thinking the bike was built and run very few times if at all, it seems to have the "right" bits but maybe was never dialled in correctly then again it was on the road and I had heard it had been hill climbed???
The chokes on my 36mm pumpers, Works as a fast idle, So wants no throttle !, Throttle would mess it up,
They work well on mine, If it plays up, Even hot, A bit of choke and shes away most times.
I put the chokes off almost as soon as it has started, Because it's a bit fast.
My chokes are cable.
I would try a weaker slide, I just filed a bit off mine !.
Once the plug is your colour, I would put it in the bin.
That plug gap look too big ??, Not sure what BTH say but I would try 20 thou.
Cheers Bill.
They work well on mine, If it plays up, Even hot, A bit of choke and shes away most times.
I put the chokes off almost as soon as it has started, Because it's a bit fast.
My chokes are cable.
I would try a weaker slide, I just filed a bit off mine !.
Once the plug is your colour, I would put it in the bin.
That plug gap look too big ??, Not sure what BTH say but I would try 20 thou.
Cheers Bill.
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If your plugs are blackened from running with a rich mixture there is no need to throw them out (bin them) You can clean them off by heating them with a propane torch to burn off the oil and gas, or if they are really carboned from a lot of oil burning you can sandblast them.
Although the carb settings may be out, it is the ignition that is the real issue, you will need to address this first or you will be chasing your tail.
i don't know how to time the engine or have tools to do it, how is it done. I'll give it a go if I know what to do. BUT
I'm a bit surprised that the twin head, BTH coils were put on and don't work as they should. Who has the same setup (well similar) that works? The builder was knowledgable and a very good engineer.
Why do you think it's the ignition, can I test it?
I would like to use what I have, just need to test things to find the problem, one thing at a time.
As a complete novice to this I'm afraid I'll need some tips please.
I'm a bit surprised that the twin head, BTH coils were put on and don't work as they should. Who has the same setup (well similar) that works? The builder was knowledgable and a very good engineer.
Why do you think it's the ignition, can I test it?
I would like to use what I have, just need to test things to find the problem, one thing at a time.
As a complete novice to this I'm afraid I'll need some tips please.
I know nothing about this new stuff, Maybe email BTH with all your details Of what you have, Cheers Bill.
The bloke at BTH hasn't got a clue, He told me half the mag's he sells are twin spark, and no one has any problems. That must mean there are a lot of bikes that are not used. You can not run a twin spark ignition that has the same advance curve as a single spark set up, the range of ignition will be too much. A stock BTH you set up will have 4 degrees retard and 34 degrees full advance. On a twin spark, the full advance needs to be 28 at the most probably less, so the retarded position is 2 degrees after TDC this will make the engine hard to start. The only way this would work is if you had a fixed timing BTH and used an original ATD with the travel reduced to 12 to 14 degrees of movement. You will need to check the ignition timing to see what you have, but the easiest and cheapest fix is to run it as a single plug. I have done exactly this to a 600 Comet engine here that has a twin spark BTH now only running one plug, ignition set at 34 degrees, engine starts very well.