wont stay ticking over

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druist
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I know this is more for carbs but i didnt get any responses previously and wondered if anyone goes in that forum much.

Anyway, I cant seem to maintain tickover without the scoot stalling after i take my hand off the throttle. If i put the choke on it stalls suggesting its too rich to start with. I have tried with and without filter. I have moved my pilot from 50 to 48 now to 45, I am wondering if its the slide 40, before i buy another i wondered whether anyone has any ideas; also as i have just about finished running in any suggestions generally on the below setup would be welcome. Thanks, Drew

Settings SIL GP1978 150 with tunes 175 top end, with Scootrs Expansion, 19 deg btdc,175 tuned iron barrel, remote filter
Dellorto phbh 28
3%.synth mixture
mixture screw half turn - but tried various
Atomiser = AV264
Needle 1st clip x13
Slide 40
45 pilot
70 choke
112 main
lammydave
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Main scooter: Li150Special RT195
Location: Ashford, kent
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had a similar problem...

just make sure befor you check anything else that your choke plunger is fully seated when you are not using the choke...
Li150 S2 1959. Li150 Special 1964. GP125 1970. Jet 200 Performer 1981. 1967 Sx150. 1959 Li150 S1. 1968 li125 Series 4
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druist
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good thinking but sadly not it. All seems fine at bothe choke ends
J1MS
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druist wrote:I know this is more for carbs but i didnt get any responses previously and wondered if anyone goes in that forum much.

Anyway, I cant seem to maintain tickover without the scoot stalling after i take my hand off the throttle. If i put the choke on it stalls suggesting its too rich to start with. I have tried with and without filter. I have moved my pilot from 50 to 48 now to 45, I am wondering if its the slide 40, before i buy another i wondered whether anyone has any ideas; also as i have just about finished running in any suggestions generally on the below setup would be welcome. Thanks, Drew

Settings SIL GP1978 150 with tunes 175 top end, with Scootrs Expansion, 19 deg btdc,175 tuned iron barrel, remote filter
Dellorto phbh 28
3%.synth mixture
mixture screw half turn - but tried various
Atomiser = AV264
Needle 1st clip x13
Slide 40
45 pilot
70 choke
112 main
Going on these details and not seeing the scooter I would have thought it would have been more on the lean side than rich but as I say I havnt seen the scooter Im sure someone will come along with a better Idea of whats right or wrong.. :?
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druist
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Thanks for the reply, do you not think the slide may be making this too rich? Or is is when the number goes up eg 50. I have moved the needle down a clip (although i am only talking about idle) and tried a 50 pilot but this was too rich.
Daggs
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Strictly speaking the tickover is controlled by the 'tickover setting' and the 'mixture setting'
To adjust the tickover, simply adjust the screw on the side, that lifts or drops the slide. With the tickover a little fast, turn the mixture screw until the best running is found, then turn the tickover down a bit.
This must be done with the engine warm.
The slide itself does not play a significant part until the mid-range, along with the atomiser and needle.
The main jet then controls quality of running at speed.
Make sure there are no air leaks and check (again) the choke is shutting off.
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druist
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so air leaks even though choke is turning it off after a min?
Daggs
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druist wrote:so air leaks even though choke is turning it off after a min?
I don't know what you're saying here?
Perhaps it was the way i wrote the last bit!

Check the choke is shutting off properly. The choke makes the mix rich.
Check there are no air leaks. e.g carb. loose on manifold. Manifold not tight to barrel
J1MS
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Daggs wrote:
druist wrote:so air leaks even though choke is turning it off after a min?
I don't know what you're saying here?
Perhaps it was the way i wrote the last bit!

Check the choke is shutting off properly. The choke makes the mix rich.
Check there are no air leaks. e.g carb. loose on manifold. Manifold not tight to barrel
What Daggs is saying is the correct way to go about getting a tick over.... even if you do have a light air leak the choke may well richen the engine enough to stall it, and even stop the engine with an over rich mixture... but it dosnt mean that there isnt an air leak... worth checking then try again what Daggs says...
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druist
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can see what you're grettin at, chears, wondering if it might be related to my electrics now as i am having problems on a new ignition. Thanks ppl.
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