Crap low revs running

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vRSG60
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Posts: 266
Joined: Mon Apr 02, 2012 3:56 pm
Main scooter: Lambretta Li125 Lambretta GP20
Location: Barrowford, Lancashire
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SIL GP200 Jetex 22mm SOI-100 carb with jets pilot 45, main 123, choke 50 NGK B78S Rayspeed Fresco exhaust

Starts fine & runs fine if over 1/4 or 1/8 throttle, below that runs like a sack of spanners. If it was a car I'd say is was "missing".
Screwing the airscrew in or out makes bugger all difference, unless I screw it all the way in or all the way out.
This was a problem last year but I had another toy to play with and so it's been sat for 6 months. Problem still here now I've come to use it.
I get my kicks out on the floor.
mick1
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Main scooter: Li Avanti 225
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Not sure what plug you've got but if it's a B7 i'd change it too a B8.

If you've got the chance i'd change the carb' for a Dellorto (Jetex's can be very unreliable).
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vRSG60
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Joined: Mon Apr 02, 2012 3:56 pm
Main scooter: Lambretta Li125 Lambretta GP20
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Thanks yes should read B8 and yes Jetex are shite. Other than that not sure what to do. I have a better quality air filter on order I'll give that a go.
I get my kicks out on the floor.
dapper
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Main scooter: The Biriani Bullet
Location: Brighton (well Hove actually)
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Most suggest changing to original Dellorto jets. Available from Splat Shop I believe.
Compact Toolbox Flywheel Holder
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vRSG60
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Joined: Mon Apr 02, 2012 3:56 pm
Main scooter: Lambretta Li125 Lambretta GP20
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I put Dellorto jets in , I think! When I changed them.
I get my kicks out on the floor.
Chris in Margate
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Main scooter: Lambretta 1964 225 Special
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Jetex when set up correctly are NOT crap !
Strip carb and clean pilot jet circuit. Fit 50 pilot.
Check that float is free to swivel.

If that don't fix it it may be electrical.
B7, B8, B9 won't make diddly squat difference to your posted symptoms.
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vRSG60
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Posts: 266
Joined: Mon Apr 02, 2012 3:56 pm
Main scooter: Lambretta Li125 Lambretta GP20
Location: Barrowford, Lancashire
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Thanks Chris. I fitted a new CDI which helped last year when it was very difficult to start. I have a 48 pilot I could try that.
I get my kicks out on the floor.
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