Backfiring when starting

[Shiny]

Hi all,

Every now and again my 05 EC300 backfires a 'chuff' sound out of the pipe when kicking it over, normally when giving it a bit too much gas. I'm thinking it's timing related and have had a small mess around with it before. I've elongated the hole in the locking tab on the stator and advanced the timing slightly (roughly 1mm of rotation), this seemed to give me a little more top end but hasn't got rid of this anomoly.

Compared to other 2 strokes I've ridden, it refuses to start when given a wristful of throttle, preferring to be started like a 4 stroke with little to no gas. It idles and runs perfectly so I don't think it's down to jetting, which is set to the recommended UK spec anyway - #7 slide, N1EF needle on 3rd clip, 40 pilot and 180 main. Plug always looks fine on removal.

Should I give it a whirl trying it retarded from stock?

Thanks.

 

[cdn280]

Most 2T's will occasionally give out a SPOOOT sound when kicking over, and then fire on the next kick. If its continous its definately carburation or timing. Do you have or use the ignition map switch ? Try starting it from cold in the 'wet' setting which I think retards the timing a bit. Retarding the timing further will make it even softer power wise.