The pursuit for a brown sparkplug
Alright, trying to set up this Athena kit. Currently running 280 main jet and this is what the sparkplug looks like after ~250km. Looks pretty good huh? Sadly, the bike won´t rev fully, no power beyond 3/4 throttle. Running lumpy, strange. Wouldn´t say bogging but something is certainly not right down there. The question is, should I go down to 270 or up to 290? What´s your opinion? Personally, I´d want to try a smaller since almost everyone with the kit runs 270. However, since I´ve not pushed the bike that much during break-in, and the sparkplug isn´t completely black from a very rich mixture, I´d say I might as well try 290. A safer bet for sure.
And no Calum the pv is not pinned in the closed position
It's not really appropriate to be judging the fueling on break in, you need to put that engine under load and perform a plug chop to really understand how the fueling is doing.
Once it's bedded in, perform a plug chop and report back what the plug is doing then.
I'd say that plug looks a tad lean to me.
Easiest way to tell is to restrict the air flow into the bike, if it performs better then you know you need to increase the fueling.
Jens Eskildsen last edited by
This is mine (no kit though), a bit of deposits from excess oil, but otherwise tan as Hasselhoff!!
Wow! I'm impressed! I'm now running 290 main jet. Can't feel much difference. My issue is, it does not pull after 3/4 throttle. The revs go up, exhaust getting louder, I brace for the real powerband but then nothing.. Dropping to 3/4 and she goes! But there is definitely power left to scavenge. My next alternative is to try a 270 main jet. And yes I've tried the choke, no results.
Should I really be giving the piston, cylinder full throttle? I'm closing in to 300km.. Shouldn't be an issue right?
The amount of response is overwhelming