got fuel, got spark, can hear it popping but no start

[Yolandi]

Had the same crap. First day running great, second day wouldn't even start. Spark was really weak and I could barely feel it if I stuck my finger in the cap and pushed the bike. It was a bad CDI in my case.

What colour was your spark with a bad cdi? Mines currently light yellow and hardly visible, when the cdi was new it was bright blue

 

[KCvale]

Just replace your plug with an NGK 5944 (BRR7HIX) Iridium spark plug and forget about it, it even comes pre-gaped.
Best $10 you'll spend on your bike.

 

[Yolandi]

update, its not sparking with the plug installed only when its out and touching the head bolts, get the same noise with the plug lead attached and not attached

 

[crassius]

is the plug wet?
if not, then you have a fuel problem

did you try putting a few drops of fuel into plug hole then seeing if it will try to start?

 

[Yolandi]

plug is wet, tried a little fuel in the plug hole and a little squirt of easy start

 

[crassius]

I'd try a new plug, then try a new CDI if I couldn't check the timing - all those OK, I'd check compression

 

[Yolandi]

tried a new ngk plug, new CDI should arrive tomorrow or the next day, if that doesnt work ill see if anyone nearby has a compression tester or ill have to buy one, ordered a head gasket as well just incase

 

[crassius]

yeah, lots of folks carry a CDI & plug in their toolbag

 

[wagel]

What colour was your spark with a bad cdi? Mines currently light yellow and hardly visible, when the cdi was new it was bright blue

I'm not sure I saw any spark at all in daylight and in dark garage I saw some yellow hint of a spark when rotating from pedals at high speed with back wheel in the air. When I stuck my finger in the cap I felt it was off. It is supposed to zap you so hard that you don't need to try a second time but mine was so weak that I could enjoy the tingling all day long. Don't try this at home.

 

[KCvale]

You could have a big puddle of fuel in your crank case, seen it often in cases like this.
Pull your plug, turn the gas off, then pedal up and down the street to blow whatever is in there out the plug hole.
It's easy with no compression.