Woodruff Key Failures after lapping?

Thought I'd create a new post to consolidate woodruff key failures to determine who's still having problems and hopefully garner any new info for those unfortunate souls having to deal with this. Here's my latest sad tale and comment:

After returning from dealer with a lapped flywheel, retorque to 47 lbs and loctite, sheared yet another woodruff key at around the 16 mile mark in Thursday's Alligator enduro (Daytona, FL). This time I did NOT use the e-start. Also, got no warning. Bike was running great til the time it died. Just seemed to stall in second gear and then wouldn't crank. The total now is 120 miles and three woodruff keys. Once again had to be towed out! Found a head Yamaha tech at Friday's road race and had a nice long heart to heart. They are now going to send a factory tech to my dealer to fix the bike. They seemed surprised to learn I had the problem without using the e-start. Discussing problem with several road race mechanics over the weekend, a prevailing theory is the crank is now damaged and lapping will never work.

Anyone else still having problems? I'll update with details as soon as the bike is fixed.


I have been riding the Hxll out of mine trying to get it to fail within the 30 day warrantee period. 175+ miles and no key failure, but a constant concern. This makes me believe that it was a "production problem" as I alluded to in my February post. A poor design and the slightest imperfection in the machining at production will make it fail. Once failed the crank is worn and will never be right again. If I were you I would demand a new crank, rotor, everything. You must document your experience with a letter good enough to present to a judge if it goes that far and it might. <ul type="square"> I have been working with major corporations for a long time, and I can tell you that they will never admit publicly to any defect or "production problem". They will handle each case individually to try and keep in under the legal radar. I had a friend who was killed in a Japanese automobile when his fuel pump didn't cut off after a small collision. His car burned and he was unable to get out. The family settled for a million $ out of court, and there are many of the same model cars with the same problem on the road today.

It takes massive customer, legal, media or government attention before they will speak. Yamaha by now knows what the problem is. They are keeping quiet at our expense.

I hear ya. I am attempting to gather as much data as possible in the event I have to give the bike back or demand a new one via GA's lemon law. BTW, where are you in L.A.? I've got a place on the Panhandle and am looking for riding places locally.

175+ miles and no key failure, but a constant concern. ... If I were you I would demand a new crank, rotor, everything. You must document your experience with a letter good enough to present to a judge if it goes that far and it might.

Dude, chill out. IF yours breaks, give them a chance to fix it first. Call the dealer before you call a lawyer!

Unless they keep breaking and Yamaha starts stiffing owners after the warranty period, it's not even worth worrying about.

...and this issue about the fear of breaking while on the trail is hogwash. That's always a danger while trail riding. I've lost a whole lot more chains and cables than flywheel keys.

IF yours breaks, give them a chance to fix it first

I'm not waiting for MINE to FAIL!Have not had a key fail with 6 street miles on it yet but talked to my dealer today and I'm bringing it in Sat. so they can lap the crank and retorque.The dealers in my area had a meeting with Yamaha guys and thats what they say there doing about it so if nothing else there will be a paper trail on my WR. :)

03 WR450FR-grey wire mod.,Works connection frame guards,Pro Taper Bars,Carbon Fiber front & rear disc guards,C.F rear caliper guard :D

gloft, let me know next time your headed south and we can set up a ride. I will make most of the remaining SERA Enduros. Send a PM for more info...... Number82, If 3 key failures in one month is not too many, then how many failures is too many? If someone drives 250 miles to go to an Enduro, spends a night in a hotel, and eats out, he has spent $200+. Then his new $6,000 bike breaks, while 5 year old XR400's whiz by him, you can expect him to be pissed. It not like being at the MX track where you can push it a 100 yards to the truck. Its a royal pain to get a downed bike out from 10 miles in a single track trail.

If 3 key failures in one month is not too many, then how many failures is too many?

Zero sheared woodruff keys in 175 miles = 0% failure rate. If you're that freaked out about your 100% reliable WR, then sell it and get something else.

The only concern I have is that someone else will show up at Budds Creek next weekend with a WR450 and I might have to settle for 2nd place :).

Alabama Rider, Don't know when I'm headed back to L.A. but I'll definately look you up! These guys talking patience obviously haven't had to be towed out 40 miles in the woods on a cold night. Hope they don't have too either.

You guys are going to have a very hard time with the lemon law. This is not a street legal bike, it is race, rec machine, outside the scope of any "lemon law" in any state. Good luck working with your shop after you file any frivolous paper work in civil court.

There are some on here making a lot of noise about this issue and 82 points out a legit thing. If your unhappy with the bike sell it. There are lots out there that would want it, these things are in high demand. Several of the complainers are old XR owners. You can probably get a brand new, year old model closed out, save some money, and be happy or you can keep the WR450 and worry. If I was that worried about it I would sell it and get something I would enjoy riding without the worry. But to each there own, some enjoy the stress I guess......

I'm concerned because

in the 35 years I've been riding,I have never seen or heard of woodruff key breaking.

My 2000 WR400 was stone reliable as was my 2001 WR250. I hope my 450 is as reliable.

No problems, no worries.

im concerned because i could very well end up towing adam out of the woods this summer.

or...OMG... he could be towing me out.


I already have the law firm of Suer and Shyster working on a class action suit.

If your concerned Adam I have a a 2000 WR400 in great shape, I'm on the list for a WR450 should be here in a week or 2. I would be willing to trade you and even throw in $1000 bucks for your unreliable WR450 :) Didn't think so but it gives you and out if your reallllllyyyyyy worried. I keep offering a trade of some sort to the guys that are worried but no takers.

Worried not crazy. :)

Eric, it's gonna take more than a WR450 to get me "out of the woods." LOL. :)

I have read these posts for sometime now and knew about key problems. So when my WR 450 came in I asked

the dealer to check flywheel torque.The torque was checked and I was called for pickup of my new bike.When

I arrived it would not start. The first key sheared. Lapping compound used on tapers as recommended by Yamaha

and I took my bike home the next day.Did free mods put in EMN needle and 40 pilot jet 160 main jet excellent

response.Bad weather kept me from riding for 2weeks March 9 I rode 23 miles sheared another key.Not while

starting it happened when I slowed for a mud hole and tried to accelerate quickly.Two miles from the truck in

very rough country towed out by a Honda four wheeler


Yamaha is working with dealers on this, you need to work with yours if you're having problems. My dealer called Yamaha when ours broke after lapping and they said to replace the crank and rotor. Cranks are plentiful but seems there are no rotors to be had anywhere, so we wait.

Man I wish I had read these post before I bought my new wr450 2 days ago. Could have had a new KTM 525 for the same money(when you consider all the crap you have to replace on the wr450 right out of the box) boy I'm hopin' this was not a big mistake.

who will pay for the crank and rotor after the 30 day warrantee expires?

Has yours broken?

You would complain if you found Anglie Jolie in your bed.

"Oh no she has a pimple on her ass".

Quit whining and go riding.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now