Help with my 450 WR

My 450, which I have been riding very carefully, changing oil every 500 miles, cleaning airfilter every day, just locked up on me after making a weird sound TODAY. It has 1700 miles on it of desert riding. No racing. I am terrified that it is a cranckshaft problem. Coudl it be this woodruff key issue that I have been reading about? It is a 2003 the VIN is WYRF02Y56A000582. PLEASE Help....

My woodruff key has not sheared after 900 miles, but the problem you described sounds like what I've heard about - a sheared key. I hope not! Let us know.

I doubt it is a sheared flywheel key if it "locked up". I have sheared mine twice and it just won't run, and the electric start just spins, without spinning the engine. Remove the screw plug in the middle of the left side case, and while you hit the starter button, see if the crankshaft turns. If it doesn't, you sheared a key.

Jeff

when the flywheel key goes it throws the timing all out of wack. it will not lock the motor so that it won't even turn over with the kick starter. pull the small round cover on the flywheel side. it is held on with two bolts. there is a small mark on the top, make sure it goes back on the same way. pull out the idler gear that is under the cover. you will be able to see the other (smaller) idler gear. the outer end of it's shaft is supported in the side cover. a couple of us have had part of that area of the side cover break. it is only a small half circle of aluminum, but if it made it's way into the motor it could lock it up. the chances of this being your problem are slim, but it's free to check and will only take about ten minutes. from there you can pull the spark plug and look for debris on the tip. you can also drain your oil and pull the filter. if the motors torn up there will be peices somewhere. good luck.

Well I found a gear in the electric strater broken. But the kick strarter is locked. So I going to remove the flywheel, and eventually the right case to look at the kickstarter mechanism. Can the flywheel problem create also a problem with the kick sarter mechanism? I drained the oil and it was fine with no debris. :)

Not sure but good luck.

HELLO MTRABLUE. THATS THE SAME THING THATS HAPPENED TO ME REF MY POST STARTER DISASTER. THE CIRCULAR PIECE OF ALLY THAT HOLDS THE GEAR SHAFT IN PLACE. ITS NOT VERY STRONG BY THE LOOKS OF IT. WHAT CAUSES THIS? DO I NEED THE 04 UPGRADE. ALSO THE GEAR ON THE STARTER MOTOR GETS CHURNED UP AND I WAS TOLD BY A YAM DEALER THAT I NEED THE WHOLE MOTOR (OVER £200) AND CANNOT BUY SEPERATE. SOMEONE ELSE THAT I SPOKE TO SAID YOU CAN. I NOW HAVE 2 MOTORS WITH CHEWED UP GEARS!

tiout, what i was getting at with the kick start was to seperate the flywheel key issue from the rest of the motor. now you need to seperate the crankshaft/top end from the transmission to figure out which is locked up. if you have found a broken gear there is a good chance a piece of it has gotten between a couple of other gears. i don't want to make you think i can fix your bike over the internet but we may be able to get you pointed in the right direction. if you don't mind doing some work try taking the side cover off that covers the clutch. take the clutch plates out. the outer part of the clutch basket turns the crank, the inner turns the transmission. turn the inner and try to shift gears. if you can get through the gears your probably okay there. if not you may have at least located where the problem is. if you have made sure there is nothing jammed up with the flywheel(idler gears have been removed)and the transmission is free, try turning the outer part of the clutch. if it is still locked up (aside from engine compression) your problems probably in that half of the engine. i hate to say it but this is where my two cents(maybe less) worth of advice ends. i couldn't even begin to tell you how to diagnose the top end or what gear might be jammed. i hope i helped a little. hope you pulled the filter out when you drained the oil, any engine debris will be in the filter. good luck.

Thanks. Mtrablue for help. I will work on it and keep you posted. Hopefully one day you can come try the bike in the Tassili (Sahara) where it is. Here is a picture of it while it was still galloping...

wr1.jpg

dossyboy. go to a post by TheBlueOne titled "wr450, check this out". it should be on pages 23 or 24 of the postings. he broke his also. the side cover becomes the weekest link when the flywheel and idler gear1 don't slip. we're both kick starting our bikes till the '04 parts become available or yamaha decides to fix the '03's. and yes my starter shaft is chewed up also. i don't think there are many options on starter parts.

turns out the distribution chain got loose after 2000 miles and jumped a cam gear and the valves hit the pistons.... the Yamaha dealer says he has never seen that. What would lead to a chain getting loose so soon? I really want to find out so that it does not happen again. (Oil? bike being riding at low RPM? Gasoline quality?.....???)

Please help with any insight you may have.

Thanks

I just cant figure out why your chain jumped. There is no way it has stretched the chain or worn the cam sprockets. So I have to think your cam tensioner loosened or broke a spring. I just have not have heard of this happening to a fairly new bike despite the mileage. :)

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