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stripped headbolts on 784 xr500, plus other questions

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Can I get away fine with helicoils for the headbolts?

The jackass I picked this bike up from did the worst job putting the bike back together I have ever seen. Didnt even use all the actual headbolts. The threads on most of the bolts look like crap, and so do the threads in the cylinder section for the headbolts.

I'm thinking just drill and heloicoil ever single one. I figure I also need a new set of headbolts as they seem very specific.

Another quick question. I picked up a ebay gasket set, to replace all the jenky red rtv that has been smothered over every orfice of the engine. The only place they didnt get is the actual center case, which thankfully they didnt pull. Anyhow, how well do those metal ringed with that blackish materia head gaskets hold up? I noticed the one on the bike is a metal shim style.

Then there is the transmission area. Do most fotehg ears normally wobble around? Like the large and small ones out front, and the chain sprocket gear? It seems like something is totally ;ed up to me, but who knows, maybe they are suppose to be like this?

Another thing I notced when I pulled the cylinder off with the sleave. There is a small portion broke off the bottom of the sleave. Doesnt seem like it will affect anything, but any idea what may have caused it?

Any help and advice is appreciated.

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1.) Can I get away fine with helicoils for the headbolts?

2.)I figure I also need a new set of headbolts as they seem very specific.

3.) Anyhow, how well do those metal ringed with that blackish materia head gaskets hold up? I noticed the one on the bike is a metal shim style.

4.) Do most fotehg ears normally wobble around?

5) Another thing I notced when I pulled the cylinder off with the sleave. There is a small portion broke off the bottom of the sleave. Doesnt seem like it will affect anything, but any idea what may have caused it?

1.) Yes. Use the longest insert you can fit in there.

2.) The lengths are unusual, but at least you have a pre-'88 bike with the normal 8mm thread and not the later ones with 9mm.

3.) As long as it's a laminated steel gasket, you are in good shape. The black ones just have a very thin coating of silicone and are not any worse than stock(which is quite good).

4.) The what?

5.) Either a ham-fisted buffoon dropped it and chipped the sleeve or that cylinder was on an engine that threw a rod at some point.

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Oh man, keyboard gremlins. The one question was about the play in some of the gears, bascally wobbly gears.

Thanks for the quick reply. I'll probably go drill the holes and tap em tonight, and pick up some long inserts tomorrow.

I'm hoping the honda dealership wont bend me over too bad on the bead bolts.

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Transmissions just about always have some backlash that comes from clearances between the gear teeth and clearances between the gears and shafts. The countershaft and sprocket will some noticeable play as well, especially since that area does actually wear out. It's really only a problem if the countershaft splines are ready to fail.

I would expect to pay $30-40 for the head bolts.

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man this just keeps getting better for me. People who dont know who to helicoil shouldnt touch a bike. Either the previous owner put the wrong thread pitch heli coil in, or ran them in sideways. That explains why the threads were shot on some of the head bolts. I ran a normal bolt from my car down in there and it ate half the lower threads :thumbsup:

So now,. it looks liek I will have to do a piston, rings, and buy a used cylinder somewhere :moon: Might be cheaper to just find a running engine...

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well after doing some searching, I may be able to salveage this thing with a timesert, not quite sure though. looks like it is drilled past 10mm.

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I feel for you. A couple weeks ago I went through something similar while repairing my old man's '84 XL600. Half of the head cover bolt holes had been 'coiled at some point and the ones that hand not were pulling out and causing a major oil leak. I pulled the head off and 'coiled the rest, yet as I was sneaking up on the last bolt, the thing almost came up to torque and then stopped getting tighter. I knew that was bad, so I took it apart again and out came a Heli-Coil along with a bunch of aluminum.

If you can get Keenserts/Timeserts to work, great; they are stronger than Heli-Coils anyway. It is also neat that they are available with SAE external threads and metric internals. I have some with a 3/8" on the outside and 6mm inside. If the holes are really blown out to 10mm, then that may be the only option.

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wel, I couldnt get time certs, but I got something as good or better. They are called king I believe. It's a m12 x1.25 outside threaded sleave with a m8x1.25 inside. Has 4 prongs that you push down after you thrad the sleeve into the hole and it locks it into place. Hopefully going out to m12 wont screw anything up in the cylinder. as its 27/64

I also learned the head bolts on the exhaust side are no longer available through honda according to the local dealer. I suppose I will go to the local major bolt store and see if they have any grade 11 allen head bolts in different sizes.

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The parts fiche from a place like Bike Bandit should have the the bolt length listed, so that will at least give you something to shoot for when looking at the fastener place. Heck, BB or Service Honda might even have them still.

It sounds like you got something like a Keensert, just under a different brand.

966006.jpg

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