Add me to the list of those with consistent hot start issues, especially at high altitude. I picked up a leftover 2012 WR450 a couple weeks ago. First day I brought it home, it took me over an hour to figure out how to get it started. I was swearing up a storm that I had just dropped 8 grand on a pile of crap that wouldn't even start. Called the service manager at the dealership and he said it's a common issue due to low compression in the cylinder because of the nikasil coating on the cylinder walls. He said to get the thing broken in, and it would start better. I had even read through the service manual and tried starting it how it says to do it. After kicking it over a few times and rubbing its private parts in the proper direction to get it hot and bothered enough to fire up, I finally got it started. I did several rides where I'd get it HOT and run it hard, varying RPMs. After the initial ride, the next few rides the bike would start cold without issue. I did not try starting the bike hot, as I was adamant about completing full heat cycles on the motor for aid in break-in.
So, that leads me to Sunday when I got the bike up into the woods for the first time. Bike would not start cold at 9k in elevation. I had to screw with it to get it to start. Great start to the day. After a little bit of a ride, I shut the bike off to listen for my wife who was behind me. After that, could not get the bike started. Once again, I felt like I was performing religious rituals, or like I was trying to sleep with a woman who needed extra foreplay. Took me about 5 minutes before I could get the bike running again. Never have I been so regretful of any vehicle purchase. NEVER. I have numerous other off-road fuel-injected vehicles that start on the first crank, every time, without having to fiddle with anything. Needless to say, this bike is a damn lemon. I'm about ready to retain an attorney and have a little battle with Yamaha, up to repurchase if necessary. I shouldn't have to do anything to make this bike run. I should push the button, and it should start, EVERY SINGLE TIME. Well, as the day went on, I finally figured out how to get it to start most times, but it was still a huge PITA, and not consistent. A little throttle crack would often cause a backfire, and sometimes pulling the starter knob would work, even though the manual clearly says that's for cold starts. The manual also says to use the kick start for "high altitude", but I'm not sure that what I consider high altitude, is the same as what someone else would consider high altitude. To me, high altitude is above 12k, which I pretty much never cross. Most everything I rode this weekend was just under 10k. Once, after the bike sitting for about 15 minutes, I started it back up and the damn thing was bogging down like a carbureted bike running too rich. Took several minutes of easing the throttle up, then taking off, before the bike ran normal again.
The bike had the throttle stop screw removed, as well as the air box snorkel, by the dealer. Aside from that, it's all stock. I refuse to replace the ECU, the muffler, and numerous other parts to fix a problem that is clearly a manufacturer issue. I want to replace them when I want to replace them. It's really sad that my old hunk of junk 2002 WR250 is an easier bike to start, runs better, but just has a little less power. Starts on the first kick ALWAYS, and when hot one or two kicks with the hot start pulled. Talk about additional reason to have extreme regret for my purchase.
Just called the local dealer (not the one I bought it from) and the guy said he'd have to charge me shop time for adjusting with the FI tool. That's complete BS. I am NOT paying a damn penny to anyone to fix a problem that should be covered under warranty. The guy said he had never heard of this hard starting issue, and that Yamaha has never put out a bulletin about it. He did say he'd be happy to contact them about it and see if it's something they are aware of, but that he'd have to charge me to do the work if Yamaha won't pay them under warranty. So, I guess we'll see what Yamaha says. I'll be giving them specific instructions about what has been said in this thread on adjusting the CO setting, but I'm not holding my breath.
As pissed as I am about the starting issues, I really love how the bike rides and feels. Even though it's like 70 pounds heavier than my 2002 WR250, it feels just as light and nimble. I bought this bike because I weigh like 140 pounds, soaking wet. A heavy bike would rule me. I knew this would be LOTS of power and be nimble like the 250, and that's exactly what it is once it's being ridden. Couldn't be happier in that regard.
HUGE thanks to everyone in this thread, and all the great info. I'm hopeful Yamaha will do the right thing and fix the bike without charge.
Edited by rtheil, August 19, 2014 - 01:14 PM.