Hi, so i took my 2012 WR450 for first (very short) ride today to find and see whats happening and what needs fixing after the previous owner didn't properly care for it (problems expected, got it a little cheaper than the normal ticketed price). Now heres what happened, and i am wondering what the cause is.
-very hard to start, running a fresh oil (and filter) change and 95 octane fuel, takes 15 hard kicks to show signs of life ( tried fiddling with adjustment knob on side of bike, helps a little but still very hard to start.
- once started, backfires lots. I'm talking like every 2nd-3rd combustion stroke is a back fire.
- doesn't like to idle. Have to keep the revs on if you want to keep it going, if you back them off the bike will die almost instantly, but once warmer it idles for longer periods of time, but unexpectedly cuts out eventually
- because of enormous amounts of backfiring, it is hard to control as is very jerky on the throttle, lifting front wheel one second, then no throttle response the next, making it unrideable.
The bike blows no smoke, has heaps of compression and has new battery and all electrical systems seems fine. I am hoping that the problem is a combination of severe timing issues and valve clearances very out of spec.
Really don't want it to cost much ( i don't think it should need a rebuild, as done under 9k kms )
cheers for any educated opinions.