How do you know it has "pre-detonation"? Perhaps its an air leak, or lean condition. Have you did a leak down test on your engine? What have you done to your engine... exactly. We need LOTS of details, so we can help you. Lay it on us... what modifications were done, pipe, carb, jets, fuel, air filter, feeds, piston, etc.. Do you have any photographs of the blown up engine you repaired?
What the hell does that mean??? /\ /\ /\I have a 260 Main jet air laid off
yea to both and and sorry I'm sure that doesn't make any sense I'm talking to my phone because I'm lazy lolWhat the hell does that mean??? /\ /\ /\
Back to basics, did you check for leaks with a leak down test and a plug chop?
I thought that too I check that it all looks fineHole in the center of the piston could be a timing issue, check your flywheel key and positioning of your stator.
FMF pipe with the air box lid off and 32:1 premix would prolly need a 300 main jet.
Needle on middle clip.
B8es plug.
Plug chop to confirm!
Why are you running a hotter plug? Has your head been milled? What does a compression test revel?I'm running a hotter spark plug what else can I do to make it stop
Running a hotter plug will not change the combustion temperature.Why are you running a hotter plug? Has your head been milled? What does a compression test revel?
Yes stock timingI started to get some with my +4 timing. So I backed it off a degree and it went away. You have stock timing?
I'm in MissouriTHAT /\ !!!!!!
but I'll say it again............
260 main with FMF, lid off and fuel/oil mix is way too lean.
no way a plug chop came back correct !
290 - 310 main depending on your elevation.
if I remember correctly your in virginia near sea level ?
sea level requires richer jetting than higher elevations
plus...... run 93 octane, higher octanes fuel helps prevent detonation.
I really don't know sorry budWhat's your altitude?