03 xc800
I put a new silencer(slp)and the sled wouldn't run on prem,I had to run with the switch on reg for it to run??

Next ?? champion plugs are they the only plug you can run or can I run ngk.

NGK part # :

BPR9ES

Are you sure about the premium switch?? Just doesn't make sense that after a can it won't run in that mode. It ran fine in that mode before?