Scooterotica

lambretta gp 150,standard tune,electronic ignition,new 22mm jetex,starts no problem but will not tick over,need to use throttle to keep it running,carb adjusted all the way,tried another jetex but just the same,any advice?

you will probably find BOTH Jetex's are U/S.

They either work or they don't unfortunately.

Was it running OK before? Done anything to it?

Chris

Assume you've checked the fuel line, filter, flow of flow from tank ?
Air inlet in cap blocked ? Water in fuel ? two stroke oil in carb bowl not
mixed right ? Shake the scoot a bit ...or clean out carb.
Main jet blocked ?
Carb top loose ? worn throttle slide ?

If not fuel related...change the Cdi ........ G

it was a 175 but its back to standard new barrel piston head,it did tick over slightly faster but not much still had to keep it going with the throttle,thought if the carb was knackered it just wouldn't start at all,

sorted,turns out that new jetex carbs don't come with a carb top gasket,find that strange,fitted one and a new omg fast flow,running great now,only that gearbox noise to sort out now.
brian.

what exactly do you mean by "Carb Top gasket"?

one berween the carb top and body,
brian.

thats a very very interesting point Brian.

My initial response was going to be "there isn't one anyway", so much so I checked the 5 Jetex's in my spares box- not one had the "gasket" in place.

However..................looking at a Jetex carb gasket set I've got hanging up which I bought off Ebay years ago, there is indeed a gasket for that area.

You learn something every day in this game!

It could well be then that the ommision of this gasket has given rise to the "Jetex Problem" over many years.

thanks for that

Chris

chris,it got me thinking,i luckily had a gasket that was part of a rebuild set,i also checked scooterestorations website and on their exploded diaghram for the jetex it has one.
brian.

Wil, check mine tommorow