08 WR450F Starting issue - one sputter & backfire, dead
Posted September 25, 2012 - 07:50 PM
The bike always fired first kick or swing, but after going on dirt trail it started sputtering and backfiring and wouldnt go again. i pulled the carb at home and found a 175 main jet ( i thought too big but bike ran well) cleaned carby and put back in.
The bike fires once, sputters, then backfires and dies. i pulled the carb many times now to make sure i didnt miss any dirt, i dropped the fuel, changed to the suggested 168 main jet for my area, still no starty.
So yesterday i filled all day and changed the plug back to the old one i replaced and the bike started first thing, ran beautifully, took it around the block, dies half way so me pushy back. Change out plug again to new one, what do you know, it works again. So at this point i believe my problem is on the actual plug that clips onto the coil pack that sits on the plug as it works fine every time i WDF it.
Has anyone heard of this, does it make sence? I must add that on the dirt trail the the problem increased every time i went trough water untill the bike eventually died.
I have now degreased the plug and wires, dried it and siliconed it up nicely, hopefully IF my diagnosis is correct my prob is solved, but i would love some forum guru opinions.
Posted September 26, 2012 - 03:38 AM
Posted September 26, 2012 - 05:01 AM
Posted September 26, 2012 - 07:47 PM
Update... Yesterday I thought all was sorted after the silicone job, but no, bike runs and idles, but on throttle dies.
Bike starts very easy then as soon as I touch and turn or wiggle the coil pack on the plug it dies. I got it running reliably by pushing the coil pack in as hard as i can, I just hope it stays there, today ill find out what replacement cost is or if I can try one on appro, to see if it solves my problem.
I dont think the coil pack is nacked as it should stop working consistently as it heats up no? but never the less, my situation seems like a new thing or not heard of on a WR, at least now its documented.
Mongial, I checked my wiring directly off the bat, all seems good, but i will keep that in mind.
Posted September 27, 2012 - 01:43 AM
Posted September 27, 2012 - 08:44 AM
I think I had 2 separate issues one was possibly the 2 wire in the plug in the pic that was shorting out and the other like I mentioned is the coil pack that wasnt sitting tight enough.
Posted October 01, 2012 - 10:36 AM