My

Gday, my money is on a fouled plug - caused by the carb or air cleaner. Or a really blocked exhaust. Check the plug and see what colour it is - there are many pictures on the net of what you should have. If its black it is either too much fuel (carb issue - needle, float needle etc - see post above), wrong spark plug - Champion N7YCC or equivalent, I think a BP7ES NGK, blocked air filter - clean and re-oil but not too much oil! If its pure white (which I doubt very much) its suffering from fuel starvation.

Let us know how you get on.

Cheers,

Stork

Ok have followed most of the tips given, new plug fitted, carb removed again and cleaned ( by my mate this time), not checked reeds as didn't read the post untill after done the work. Fuel line and filter removed checked cleaned OK.

My mate would not act as spark tester by holding lead cap (chicken), so have ordered the real thing of ebay, at least then I'll know ignition or fuel,

Many Thanks for the feed back everyone

Gday, how did the old plug look? (This is important - it will give a clue as to what is happening)

Cheers,

Stork

Gday, how did the old plug look? (This is important - it will give a clue as to what is happening)

Cheers,

Stork

Stork, Plug was very black, oily.

Spark plug tester (arrived today) confirmed ignition, no spark, problem at higher revs.

Ordered new CDi today

Bingo!.....let us know how you get on? Including a video?

Edited December 9, 200916 yr by HAM2

Gday, the black fouled plug worries me. You did try a fresh one and found no difference didn't you? If not hold off on that CDI until you try the cheaper option first. The fouling on the plug will probably short to ground especially under some load (higher RPM's) and may look like a failing ignition. It is true however that failing ignition can cause the fouling but I reckon that is less likely. Try a new clean plug and see if it runs OK, even for a short time.

Cheers,

Stork

Yeah as Stork said try a new plug first, I once laid my bike over to fill it with gear oil but I forgot to turn the fuel off, it flooded the engine but it started ok then shortly after I noticed it wasn't revving out, it was fine up to 1/4 throttle then it would do exactly as your bike is doing in the video, I put a new plug in and it ran fine. I think the spark plug fouled due to the excess fuel then when the revs rise the compression also rises making it harder for the spark plug to spark so the electric finds the easier way home through the oily gunk covering your spark plug.

I'd also be suspect of your stator as they said it was faulty but you say it didn't change the symptoms when you changed it.

I'd also be suspect of your stator as they said it was faulty but you say it didn't change the symptoms when you changed it.

NOT C D i , good old BVM did offer it on a sale or return basis though, phew

Gday, the bulb will tell you that it has fired. If the plug is fouled, and so is shorted, it wont show as it takes very little voltage to pass electricity through the short. Find the cause of the plug fouling and you have solved the problem. Black plugs are caused by too much fuel, or not enough air. Or the Wrong plug!. You are this far - keep going, you will find the trouble.

Cheers,

Stork

You haven't still go one of them shy-tee Beta 'kill-switches' connected up have you? Excuse my French.

Edited December 12, 200916 yr by HAM2

i'd also agree to try replacing the kill switch, as if its slightly open circuit then higher voltage will short to earth more causing this problem,

So in summary have:

Removed carb twice and cleaned out, (the only part i was unsure of was the long brass tube is blocked,top right in picture, but this dosn't seem to go anywhere anyway, should this be clear?? have been trying to post pic, couldn't work out how to so link is here.

CARB

woodruff key OK

Replaced plug

Had stator repaired,

cleaned fuel line and filter checked fuel flow from tank

tested HT with spark circuit tester

tried new CDI

removed kill switch circuit.

None of above has made one iota of difference.

As I booked a trials training day a while ago, and now its come round, it's next Saturaday, rather than miss it, its off to BVM in morning to get fixed.

Many thanks for all the useful pointers posted

Julian

Hey Julian , fingers crossed, that it's something cheap !

Edited December 18, 200916 yr by HAM2

C'mon, c'mon it's nearly D-day..what's happening??