warm starting problem

[Andy Pickering]

i hate to mention this yet again ...but a small (1mm ) drain hole in the bottom of the hose works wonders....

LOL..

[coaster]

A permanent cure may take some time to find and please let me know if you do

Col, have you ever tried advancing your timing?

It was initially set at 18 degrees but I backed it off to 17 when I fitted the BGM last year, didn't seem to make any difference. Maybe an Augusto would help as I'd be able to set the advance to 24 degrees thern, the Jet has far more overtlap on the port timings than the muggy but doesn't suffer the same warm starting problems.........mind you, that doesn't have a filter on

Have you ever tried the 1mm hole in the elbow? I've thought about it but suspect that it would soon get clogged with 2 stroke oil, not to mention the mess on the runners.

[Andy Pickering]

Have you ever tried the 1mm hole in the elbow? I've thought about it but suspect that it would soon get clogged with 2 stroke oil, not to mention the mess on the runners.

I have with instant positive results..well it starts from warm and doesnt bog down, you do get a little discharge mainly on the flywheel cover TBH, not like the mess you get when running with open carb, you can also drop atomiser to reduce spit back, I went to AV264 to reduce mine..

[storkfoot]

It was initially set at 18 degrees but I backed it off to 17 when I fitted the BGM last year, didn't seem to make any difference. ...................Have you ever tried the 1mm hole in the elbow? I've thought about it but suspect that it would soon get clogged with 2 stroke oil, not to mention the mess on the runners.

I was thinking maybe advancing to 19 might help, or the Agusto as you say.

Hole in the elbow made no difference to the issues I had at the time. I never thought of it in terms of allowing the spitback to drain away, the issue as far as I could see was that the vapour was still hanging around in the bellows (this was the standard GP type, not the breath sweet type which weren't around at the time).

So, if you were running too rich further up the throttle, and then came down off the throttle quickly, to then quickly accelerate away, such as you would do coming out of a corner, there was then an over-rich mix hanging around in the bellows to then be sucked into the carb. This also seemed to crop up when you stopped for petrol. I may be wrong with this but that's how it seemed to me at the time.

Anyway, much messing around with different needles and clip positions did eventually resolve the issues I had, but it's a lot easier, IMO, to jet a larger carb open mouthed, or with a filter directly off the side of the carb.

Hopefully, Breath sweet bellows, being wider in diameter make it a bit easier

[Mike - - Bristol]

just to keep this going,
I dropped the main jet as I thought it was a little rich anyway, but I have started flicking the fuel off before turning off the engine
and I put a small hole in the hose. Results ? well it starts a lot easier and so far been starting better , if that makes sense.

[Andy Pickering]

i hate to mention this yet again ...but a small (1mm ) drain hole in the bottom of the hose works wonders....

Just moved this thread across to here guys (FAQ) as it does come up a lot and hopefully will give members a quick answer to this frequently asked question...which basically is why this section was set up...

[Dai.p]

Stockfoot is correct,
my engine has always done this, and always does it after I have been ridding hard on high revs and on or near the main jet, its due to the main being very rich,
If im riding round town using no throttle it starts fine when its hot.

I was goin to say this myself, ive found this happen not just mugellos but a few other kits and what i have found works best is when you pull up knock the petrol off and leave it run a few seconds so the fuel runs down a little in the float bowl then kill the ignition. then when you go to start again start with the petrol off and as soon as it fires up turn the petrol on this way at least it wont flood... hope this helps

[GP240]

me Muggy 186 used to do this every time i stopped for 5-10mins,

now when i go to start it after a short stop i never touch the throttle, just kick it over (normally 4-5 kicks) till i get a fire and then on the next kick i give it a little throttle and it fires up and revs free thru the rev range. Don't be tempted to rev it whilst kicking up a hot muggy, they dont like it up em.

Dello 28mil
102 main
JL3
Ram-air filter
19 deg btdc