brian r Posted September 13, 2004 Report Share Posted September 13, 2004 Any really good tips on replacing flywheel keys? Charlie? Quote Link to comment Share on other sites More sharing options...
bullfrog Posted September 13, 2004 Report Share Posted September 13, 2004 Take a look at the "Woodruff Key" thread in the Beta section. It addresses your situation. Ed Keep the rubber side down! Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted September 13, 2004 Report Share Posted September 13, 2004 I think the only pitfall is if the key slides back in it's slot as you push the flywheel on. This would put the flywheel out of true, and as some one mentioned, you'll be able to see it if you start the bike and look at the flywheel before putting the cover back on. Make sure you follow the torque spec. I can't remember how the torque runs on these, offhand. I'd guess 75-85 lbs. Quote Link to comment Share on other sites More sharing options...
frank Posted September 14, 2004 Report Share Posted September 14, 2004 Brian, was this your TL? My old one did it a couple of times. The question is why did it occur? 1.Improper key or key insertion. I ordered keys several times from Honda, never fit right. Ended up making a key fit EXACTLY right from a larger one. They will push back like Charlie says and prevent a good seat, especially if they are slightly too tall. 2. Improper mating surfaces. If it's sheared before, likely the surface is buggered now from the spinning with the broken key in there. Use a file to knock down any ridges, especially at the keyway, then lap with compound until all shiney. 3. Inadaquate torque when tightening, I'm sure you are using a good air wrench right? I could never hold one and tighten it right with a socket or spanner or torque wrench. 4. This one's just my theory. Timing is too much advanced and/or compression too high. That was my problem after I built the TL to 168cc. I had to run VP C4 (110 octane) to keep the timing advanced and keep it from knocking. Lugging around followed by a burst of wrist and BAM, she'd knock and shear a key. Happened twice. The rotor has so much mass that when it knocks the rotor shears itself from the momentum. If this is happening, repeat items 1, 2 and 3. Worked for me. Frank Quote Link to comment Share on other sites More sharing options...
brian r Posted September 14, 2004 Author Report Share Posted September 14, 2004 Thanks guys. It was the Gas Gas and I have bumped the timing up a bit. That's why the flywheel was taken off the first time. When I put it back on the first time I probably didn't get it tight enough. The second time it sheared I had it pretty tight and have ridden it quite a bit. I was revving it up to clean it out and it sheared at full throttle. I'm always a little scared of over tightening and stripping threads. BTW that Gas Gas seems to have more compression than any other bike I've seen. It's at least twice as hard to kick than any new bike. It was probably fiddled with by Ryan. I don't know how he had enough @$$ to kick the thing over at all! Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted September 14, 2004 Report Share Posted September 14, 2004 Check that torque spec and don't be a-scared to lean into it! The key is only for proper placement of the flywheel and it is made of soft material so it doesn't take the keyway with it if the flywheel slips. It's not intended to hold the flywheel. Quote Link to comment Share on other sites More sharing options...
brian r Posted September 15, 2004 Author Report Share Posted September 15, 2004 Well, it's back together. The key had slipped some and the back of the flywheel was a little buggered as well as the key.Part of the key had apparently slipped and got shearedby the flywheel being torqued back. I got it fixed up pretty well. I sanded the crank with a fine grit paper and I needed to run a file inside the flywheel for the key to fit in the slot. I also ran the paper inside the flywheel to take off any high spots. I put the flywheel on without a nut and it felt like it was on the crank nice and tight. I then put the nut on with a little impact. I then pulled it right off and checked to see that the key hadn't moved. It looked good. I then put it back on and torqued the heck out of it. I started it up and I saw no wobble at all. BTW, I found it much easier to work on with the stator taken off. Not that it matters, but if you wan't to see the bike, it's the one under "Alan's Ramblings" thread. That's Doug McIntosh on his head. Thanks for the tips. Quote Link to comment Share on other sites More sharing options...
alan bechard Posted September 15, 2004 Report Share Posted September 15, 2004 Brian, sounds too me like there is a little bugger or misfit on the spline. I would lap the two together by hand with valve grinding compound. You should be able to run that thing without the key if you wanted too, it is more a positioner, than a holder. (As UC said) Quote Link to comment Share on other sites More sharing options...
brian r Posted September 15, 2004 Author Report Share Posted September 15, 2004 I didn't have any valve grinding compound handy but I did put it on without a key and spun the flywheel. I looked for shiney spots and cleaned it up good. After that I could set the flywheel on the shaft without the key and it seemed to have a nice tight fit. By just setting it on I could turn the crank. After that I put it together checking to make sure the key didn't slide in the slot. I should have done that before I fixed it the first time. The first time it broke, I'm sure I was too easy on tightening the nut. Always afraid of stripping threads! Quote Link to comment Share on other sites More sharing options...
bullfrog Posted September 17, 2004 Report Share Posted September 17, 2004 If you are planning on owning and working on your bikes for several more years, I'd highly recommend saving your pennies then purchasing a torque wrench. It removes those fears of stripping threads AND provides the tool needed to properly torque fasteners all over the machine. A passable torque wrench costs about the same as 4 quarts of Silkolene (stateside) and is a one time purchase. It would be a very good investment. Ed Quote Link to comment Share on other sites More sharing options...
brian r Posted September 17, 2004 Author Report Share Posted September 17, 2004 I've got a torque wrench, I just don't have a way to hold the flywheel. Quote Link to comment Share on other sites More sharing options...
bullfrog Posted September 17, 2004 Report Share Posted September 17, 2004 I'm a vintage Hodaka Trials rider so I'm not able to visualize the flywheel you've got. But I'd bet you could bend up your own flywheel holder tool out of 1/4" steel rod. That's what I did for my Hodaka. Even a garden variety propane torch will provide enough heat for easy bending at relatively precise locations. Quote Link to comment Share on other sites More sharing options...
kevin j Posted September 18, 2004 Report Share Posted September 18, 2004 Made this years ago. Flat bar side is for clutch basket, sprockets. Round dowel pins fit slots of alternator rotor. k Quote Link to comment Share on other sites More sharing options...
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