Engine doesnt start immediately when hot/warm anymore

[iron_monkey]

Happytime engine has become significantly harder to start when cold(although still quite acceptable) and it wont start immediately when hot/warm anymore.

Back in the day the engine will immediately fire up after dropping the clutch, now I need to pedal the engine a few seconds(after the dropping the clutch) and holding throttle at WOT.

I clearly remember this all started when I left my bike sideways in the rain overnight once. Bike is still usable, it would be nice if it went back to normal.

Cleaned spark plug and compression feels normal. Even tried bending the float prongs to lean it slightly more. No noticeable fall in power, engine sounds normal when running. Could it possibly be the magneto and/or CDI?

 

[mattysids]

hmmm well if it all started with rain a long time ago then it is most definitely electrical, as any water in the fuel would have long ago been burned

Since there is no drop in power it is very hard to pinpoint the cause of this issue.

Have you taken the magneto compartment cover off and taken a look for any signs of arcing and/or build up of rust/dirt?

 

[srdavo]

Have you tried a new spark plug??

 

[motorbikemike45]

Maybe?

You could have picked up moisture in the cd or magneto which caused some corrosion. That could cause reduced voltage/less spark to the plug, especially under compression. Check all wire connections for that green stuff that indicates corrosion. Check the kill switch, the cheap ones are a cause of voltage drop, especially if corroded. Put in a new plug and see if that helps, sometimes a weak plug will make a two stroke difficult to start. Something else to check is carbon buildup in the exhaust port and inside the combustion chamber. Pull the exhaust pipe to check the port, if it is badly carboned up you should clean it out. If the exhaust port is carboned up badly then you might want to pull the head to see if there is also excess carbon build up there. Be careful of leaning out the mixture to much. It might run better lean but will get insufficient lubrication.

 

[iron_monkey]

Have you taken the magneto compartment cover off and taken a look for any signs of arcing and/or build up of rust/dirt?

Very little rust, no dirt, but the magneto appears to be oozing sticky adhesive/residue out.


I have left my bike in the rain before, but only once sideways. I haven't tried a new spark plug yet, are they known for causing similar problems?

Im sure its not carbon buildup, this wasn't a gradual thing, this happened suddenly. Only now I bothered to make a forum post about it; since the bike is still usable.

 

[mattysids]

well replacing the plug is a definite first step

if that doesn't work then the magneto is most likely at fault, followed by the CDI

does anyone know what the "oozing" might be?

never seen this on my bike before

 

[GearNut]

well replacing the plug is a definite first step

if that doesn't work then the magneto is most likely at fault, followed by the CDI

does anyone know what the "oozing" might be?

never seen this on my bike before

I could only speculate overheating, then whatever adhesive the Chinese used during manufacturing turns soft and oozes out.

 

[BAM]

sounds like what mine did it allways fired right off but the last couple rides had to pedel to get it to go ran better warmed up but not right turns out intake gasket was bad you could see a part of gasket missing must ing. parts are soild state sealed in resin if yours is leaking it my be bad good luck!

 

[fetor56]

Perhaps the magneto has moisture in it from the rain...take the cover off & inspect inside.If your in any doubt blow through it with a hairdryer.
Seal where any moisture can get it.

 

[iron_monkey]

just an update. The culprit was the CDI.


The engine now idles fine, can do it noticeably more slowly, and hence its now very quiet idling. I forgot what it was like normally.