I'm back again....for those that have chipped in on my other two posts this year with my never ending list of problems with my 2018 YZ450F.
Here we go:
I've replaced two starter clutches on this bike already this year and am now on my third. While I was at my last race on Sept 2nd the bike was having trouble starting. Got home from the race and cleaned up the bike and behold all it would do when you tried starting was buzz. With no kickstart, and starter clutch I resulted to bump starting. I did this a few times and it had no problem starting up. I let it sit for about 30 minutes before I was going to go ride and I went to bump start it just one more time. No fire or anything.
It's been sitting in the garage for a month now while the starter clutch was on back order (surprise). We put the new one in tonight and it did not solve the problem. We began to investigate more and found out that the timing has jumped 4 teeth! It is completely out of spec.
This is as far as we've gone, but suspect the whole motor will need to be pulled and the valves are completed destroyed. However, my question for you guys is how in the hell could this possibly skip? The chain is not out of spec nor any chipped teeth.
The oil has also been turning really dark for about a half month prior to this.
For those that never got to see my other posts this is my second motor in this bike. The first one went at 6 hours, and was replaced at "discount" (LOL) from Yamaha after 5 weeks of them trying to diagnose the problem with no luck. Starter clutches $600 a piece, valves needing to be shimmed, I had the gas line connector come apart (more likely fault of dealership with switch), and now this. The new motor would have less than 25 hours on it and that's pushing it.
THIS IS NOT DUE TO POOR MAINTENANCE. I am a regional pro here in Canada and have been racing for 18 years. This bike has been nothing but a nightmare and will have more money tied up into it just trying to make it run than what a new one off the floor would cost.