04 400ex pings under load

[lilwhitetruck]

just put a je 10.5:1 piston (stock bore) with stage 1 hot cam in. also have white brothers rev box, dual custom exhaust and 170 main jet(stock carb). if i lug it to much or am just going in 5th and try to accelerate to quickly. the engine will ping. i am running 92 with octane boost. what else can i do more octane, or adjustable cam gear. thanks

[2004exrider]

Not 100% sure on this but i think that aftermarket rev boxes have an advancement in timing on them, since you have a high compression piston in it try taking the rev box off and put the old one back on and see if it still does it.

Jimmy