I'm having trouble getting my 85-86 300 Professional to start, am thinking it may need a new plug and not sure the one in it is the correct one. I'm getting white spark and there is plenty of gas on the plug so it's getting fuel. It was running when I got it but the carb leaked plus it wouldn't idle so I took the carb off and cleaned it with carb cleaner and compressed air. I put it back together ,now it won't start, I figured a plugs cheap so I'll make sure to get the right one for it. Any other ideas? Thanks, Scott

Hey Scott,

In my 305 i am using a NGK BP5ES plug.

But you wrote you took the carb off and dismanteld it, if i were you i would check if i put it together correctly before i changed the plug.

What you write about a white spark, thats ok, it means your ignition and your plug are ok.

What i read is that your plug is wet?

If that is so it means your engine is getting to much fuel.

So it seams to me that the plug isn't your problem but your carburator.

I've had the same problem with my 305 once, the cure was lowering the needle one step, you can put it in it's lowest position without anny problems.

Also there is a small hose going over from left to right on the Déllorto carb, i have heard from people when this hose is leaking it can cause starting problems and your bike won't idle properly.

goodluck and let us know if the problem is soulved.

Jan- Willem

Thanks for the info, I need to get my butt in gear on the Fantic as I know I'm missing loads of fun. I've been busy getting tires for my Guzzi's and Benelli and weather permitting riding them when not working. I think I have one too many bikes in the garage for the time and money I have, but I ain't complaining I'm enjoying life the best I know how. I'll get back as soon as there is news. Thanks,Scott

I think I have one too many bikes in the garage for the time and money I have,

That is not possible.......... one can never have too many bikes!!

Your right you can't have too many bikes but keeping them all running can be a problem. I got to work on the Fantic tonight with no luck again. I have done the following: replaced the 2 overflow lines, moved the needle to the bottom clip position, raised the float level. It soaks the spark plug after the first 2-3 kicks with no choke on. I'm not adding any throttle input when kicking. Should I keep raising the float level? The bike ran fine when I got it but it wouldn't idle, it seems Ive buggered it up some how. Scott

Have you drained the crankcase ? May be a build up of fuel.

Try starting with petrol off, or only on for a short time.

Or the seal/oring on the choke plunger seat is done ...

And on these wonderful old bikes (of any brand ! ) Always turn off the fuel when your not riding it !!! (first thing I taught my kids !!! ).

Does 2 cycle oil have a self life? The Maxima I mixed with ethenol free gas is probably 4years old, could this be my problem? I'll get some fresh stuff and give that a try.

May be ethanol free gas but it has probably lost it's volatility,which could make it puddle on the plug.New premix is a must!. You'll likely have to remove the plug,kill the spark and put it in 4th gear and push it around to pump out the accumulation in the crank case. MAKE SURE you kill the ignition! I won't keep gas nowadays for over a month,goes into my Jeep and mix up fresh!

The gas is three weeks old ,it's the pre-mix oil thats 4 years old. I tried a new plug, no luck starting but this plug has a yellow spark instead of white. Next step, new gas and oil I guess. Thanks again,Scott

Take the plug out kick it over to clear the head then put a few drips of petrol down it.put plugin If she starts and dies it carb probs