Ngk BR9ES
Could be a few things. Possible to be the CDI box or the Stator.
I need more info make , model , engine size.
.028"-.030"
Many things can cause a snowmobile engine to back fire. Ignition coils ( spark plugs, coils) or water in fuel. Check these and maybe it will solve your problems.
Use your spark plug wrench to adjust your rear suspension
simple,design,it doesn't effect cylinders that are not on compression ,it allows single spark controll
go to ngk.com type your model in and they will tell you
i took my arctic cat for a ride went maybe 60 mile ran good then two days after went out to start an wont start an no spark
on a snowmobile all you do is take out the spark plug, take the bolts off of the studs and take the head off
i run 40-1 in mine but thinking of 50-1 spark plugs were a bit dark
by a snowmobile