Starting Problems

[soulfecker]

I'm having problems with starting my scoot. It is a relatively standard GP200 setup, originally I had a 30mm delly and a casa megaphone exhaust, and it used to start & run very well. I did do a full rebuild last year, and it started & ran OK. I then had some starting problems, i.e., it may start first kick, but if not it may start on the 20th! basically due to flooding. I recently put a Scootopia 22mm carb on & it's no better, but I'm keeping the carb on. Last week at an open day I put it on a dyno, and apart from it being slightly rich on tickover(once I got it started), was good all through the rev range, and giving 12 HP at the crank. I've fannied around with the pilot & mixture screw to no avail. I then found that it would start with the air filter off, and once warmed through I could replace the filter and it runs sweet as a nut, but lean with it off. The question is could it be a weak spark, when kicking, stopping it from catching unless it has a lean mixture, but once running the flywheel is rotating faster giving a better spark. This possibly being caused by a de magnetised flywheel, or too low or high pickup. The BGM LT coil is 530 Ohm & the pickup is 112 Ohm, and it is one of the first batch of BGM stators but with a new LT coil & pickup. When rebuilding the engine, I did change the crank, so if it is machined differently to the previous one, then the flywheel may be higher or lower that before. When rebuilding, I checked the piston clearance, I can't remember the figure, but it was within spec according to Stickys. I also changed the rings.
Sorry this is so long winded, but I'm running out of ideas.

[coaster]

What sort of spark do you get from the end of the lead with the cap unscrewed? should jump 5-10 mm. If not try changing the lead and then try another CDI....you did say you have changed the plug and cap already?

[soulfecker]

I have tried a new plug, and re connected the ht lead. I've been busy looking at the carb side of things, but starting on the ignition tomorrow, including new HT lead and cap. I was just bouncing round my own thoughts, and seeing if anyone else thinks that I may be looking in the right area. The thing is with these wonderful machines what looks like one thing could quite easily be something else!

Paul

[soulfecker]

Another quick question is, there is a lot of talk about the height of the pickup, mainly referring to the newer BGM stators, but how do you measure it. is it from the top of the flywheel at the opening to the top of the pick up? if so, what should the measurement be(Indian flywheel)?

Paul

[sunrisemac]

you say you have a lot of difference with air filter on or off, did you replace or change the filter for a different type?

[soulfecker]

Brand new standard filter. I tried with an old foam filter I used with the 30mm, and it appeared to be better. Thing is, it would.probably run lean and I want it standard as poss.

Paul