TM 300 spark plug problems.

[Ronni]

Hi,

My friends TM 300 Enduro is constantly destroying the spark plugs (not fouling them). This happens only when riding in tight conditions in 1 or 2 gear at low revs. He has tried different jetting and oil mixtures to try to avoid this problem and he is only running high-octane fuel. But nothing seems to help. Is it the ignition or perhaps the compression ratio? Has anyone got an advice for him how to fix this? Two spark plugs for every day of riding is a bit heavy for the wallet.

Thanks in advance.
Ronni

 

[TM-Frank]

When it does not foul the plugs, what happens to them?

My TM had a habbit to destroy plugs (the spark was hopping sideways instead of to the outer electrode) when the pilot jet was clogged. Maybe you just clean the carb and that's it.

You have the correct plugs installed? When my bike was new there was a fine wire plug installed which fouled quickly, due to rich jetting and lots of low rev riding. Since then I use NGK B8ES (which are a lot cheaper) without any problems.

 

[Ronni]

A) It acts normally.

B) The carb has been inspected and it looks ok.

C) NGK B8ES is also what he uses.

Any other suggestions ?