Hmm, so you see wzak there is no such thing as a 'standard'

You do not need to be afraid to experiment a little if you like. For your engine you do not need a glow bar plug or a short reach plug or a button head plug or a four stroke plug and as downunder said a medium hot plug would be appropriate for your engine If you were running much higher nitro than normal for your application then a colder plug would be indicated.

Some good choices would be:

OS #3/ #8

K&B 1L

Fox 1.5v long

Eyna #3

McCoy 059