Possible woodruff key on '01


4 replies to this topic
  • myoung

Posted January 03, 2007 - 06:21 PM

#1

Hey guys, I posted up a little while ago about a bike I was putting cams in. I was not able to get it to start after the swap and was wondering about possible bent valves.

Anyway, I did finally get this thing to fire, but it was running very erratic and making a lot of strange noises, eventually it shut off and wouldn't fire again. I started doing some searching and found a lot of talk about woodruff keys on '00's going bad and having similar symptoms. I didn't see any one mentioning the '01's though, was this supposedly 'fixed' in '01? Anybody know of any one who has had a bad key on an '01?

Now I'm thinking I need to find out how to determine what year this is for sure through the VIN#. Can anybody tell me which character is the year code and if it's a letter, what is the code for an '01 as well as '00? Maybe this thing is actually a '00 and it is the key that has gone south. I don't want to tear into this thing without talking to this guy first and see how far he'll want to go and I'd like to be able to give him some possibilities that could be the problem. If the key isn't a problem on the '01's, then I don't want to scare him with it.

At this point I'm still concerned there may be some bent valves as it was getting an awful lot of air coming back through the air filter intake and it runs pretty bad. My damn fitting with my compression tester wont fit in the plug hole so I can only speculate at this point till I can chuck it up and turn it down to fit. I double checked the cam timing and it looks ok, I don't suspect the woodruff key going bad would affect this either. Seems like only the gears being out of allignment with the chain would cause a problem there. The symptoms that some described that are similar to what this thing has seem consistent with both stories of bent valves as well as bad keys, I'm hoping this thing doesn't have the worst case scenario of both problems. Talk about being the bearer of bad news there.

So yeah, any help you guys could give would be greatly appreciated.

Thanks, Mike

  • myoung

Posted January 03, 2007 - 06:53 PM

#2

Now I'm thinking I need to find out how to determine what year this is for sure through the VIN#. Can anybody tell me which character is the year code and if it's a letter, what is the code for an '01 as well as '00? Maybe this thing is actually a '00 and it is the key that has gone south. I don't want to tear into this thing without talking to this guy first and see how far he'll want to go and I'd like to be able to give him some possibilities that could be the problem. If the key isn't a problem on the '01's, then I don't want to scare him with it.


So I'm doing yet another search and stumbled accross the answer to this question. Turns out it is in fact an '01. Also found a lot of feedback saying the key was fixed in '01. Were there any early '01's that still had left over key problems, or was it fixed in late '00 models? I'm leaning more and more toward the bent valves at this point. Only problem with this theory is it seems like it has good compression when I kick it and it didn't need much adjustment on the valve pads for the new cam. Anybody ever have slightly bent valves that still try to close? Unfortunately, it's not my bike and I don't want to just start tearing things apart without some idea where I need to go. Wish I never got involved now.

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  • mxis4me

Posted January 03, 2007 - 08:26 PM

#3

id get the right hose for your comp tester and do a comp test , if its weak or borderline take the same hose and put a air fitting in it and put about 80 psi thru a air regulator into the cylinder ,make sure bike is in neutral and also youll need to put the piston past the compression stroke before u pressurise the cylinder, pull off the exhaust head pipe and the carb and hook up your air and see which valve or valves are leaking the worst

  • grayracer513

Posted January 04, 2007 - 09:28 AM

#4

The "woodruff key issue" on the '00 is a problem with the straight key holding the balancer shaft drive gear on the right end of the crank, and has nothing to do with engine performance (unless it breaks and/or wrecks the crank).

You cannot do a meaningful compression test with the auto decompression cam in place unless you either determine what the cranking compression should be, or disable the AD system by wedging a piece of folded card stock under the flyweight with the weight in the "run" position.

IMO, your most likely problem is the you do not have the timing right on your cams. The intake must be correctly timed first, if using the OEM 450 cam, and the exhaust timed off of that.

http://www.thumperta...078#post3706078

Next most likely, if you had the flywheel removed, is that the woodruff key on the flywheel waas pushed out of place as the flywheel was reassembled.

After that, if both those are OK, you may have an unrelated electrical or carb problem.

  • myoung

Posted January 04, 2007 - 06:00 PM

#5

The "woodruff key issue" on the '00 is a problem with the straight key holding the balancer shaft drive gear on the right end of the crank, and has nothing to do with engine performance (unless it breaks and/or wrecks the crank).

You cannot do a meaningful compression test with the auto decompression cam in place unless you either determine what the cranking compression should be, or disable the AD system by wedging a piece of folded card stock under the flyweight with the weight in the "run" position.

IMO, your most likely problem is the you do not have the timing right on your cams. The intake must be correctly timed first, if using the OEM 450 cam, and the exhaust timed off of that.

http://www.thumperta...078#post3706078

Next most likely, if you had the flywheel removed, is that the woodruff key on the flywheel waas pushed out of place as the flywheel was reassembled.

After that, if both those are OK, you may have an unrelated electrical or carb problem.


I know the cam timing is right now with the cams I installed, but the cams were both out of time, the intake was way off, from who ever had rebuilt the top end. Of course, now I'm wondering just what kind of rebuild was actually done.

Just got home from work and am going to go do a compression check finally. Had to modify the fitting on my comp. tester so it would seat. Yeah, I know I have to disable the AD cam, that's not a problem. I was kind of wondering if there may be a carb issue, I could swap out the known good parts from my bike just to see. However, I would like to isolate the problem to his parts if I can.





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