So, just when I thought I had all my problems fixed......video

[Jimbo45]

of course, just keep the radiator topped off

Happy b-day btw

Thanks.  Too late now to load up and head out though. :upset:  I  might take it to my brother's this weekend, and ride a little, and keep and eye on the coolant.

[Jimbo45]

You cannot usually grind a head gasket for a large bore. Grinding a head gasket gets into or too close to the stamped ridge in the gasket that seals the high combustion pressure.  Look at the gasket and see how close your grinding came to this ridge in the gasket.

Like mentioned earlier, make sure the head and top of the cylinder are flat and without ANY imperfections on the gasket sealing surfaces.

You know, come to think of it, I recall when I installed this gasket, thinking the same thing. I noticed it was ground into the ridge that is pressed into the gasket and thought to myself that the combustion gases wouldn't seem to seal as well with it cut like that. But, this $35 gasket was "guaranteed" not to leak, by the seller, lol. I wonder if I can get my money back, lol. I am not going to mention where I got it, lol.

[dem3500]

I know of a place to send it out if you want. (In MI) I have them do my machine work and theyr really good and there prices are not ban. Its a small shop about 30 min from my house. Lakes motorsports

[JesseA420]

"guaranteed"

:hyp::hyp::hyp::hyp:

[dem3500]

Its probably a stock gasket some guy bought and ground it down and re sell for a few bucks more with the hopes that most people won't have a leak problem.

[Jimbo45]

I know of a place to send it out if you want. (In MI) I have them do my machine work and theyr really good and there prices are not ban. Its a small shop about 30 min from my house. Lakes motorsports

I will keep that in mind.  They do a lot of 2 stroke stuff?

[Jimbo45]

Its probably a stock gasket some guy bought and ground it down and re sell for a few bucks more with the hopes that most people won't have a leak problem.

Thats exactly what it was.

[dem3500]

Yes lots of 2 strokes. Do you know those little 90cc ATVs that all the little kids are riding/ racing ? There's the same as the predator 90's just with different plastic. Well these guys claim to have the fastest one on sand. I've seen one they set up! Its one badd little guy lol! They have never dome me wrong. My daughters blaster my banshee and my R.

[Jimbo45]

So what are you guys using for thick (don't want to run straight race gas) reliable, OEM style gaskets, that work with a 68mm or 69mm bore?  What are my options?

[dem3500]

Just an idea.....o-rings are pretty rock solid. How about getting your head and jug cut of o-rings and have your head /dome cut for pump gas. Just a thought. Otherwise I don't have an opinion on gaskets cause I've never used them lol

[Jimbo45]

Just an idea.....o-rings are pretty rock solid. How about getting your head and jug cut of o-rings and have your head /dome cut for pump gas. Just a thought. Otherwise I don't have an opinion on gaskets cause I've never used them lol

Who offers this service?

[dem3500]

Well the machine shop that I go to cut stroker domes into the stock head on my banshee. I'm pretty sure they can do o-rings as well.

[etccb]

You might want to move on to a 310 or cyl. These big oem cyl have proven that they can be head aches. Most that tell you different are looking to cash in on some $$ from you or others reading the thread by promoting the oem cyl use vs others 300 range and up options. Once that cast in sleeve of an oem is changed it is no more bulletproof then any other cyl and going bigger you can go beyond its designed water jacket and integrity intentions real quick. It sucks $$$ wise but maybe run your old stuff on the lower end $$ wise until you can get the cash together for something that was intended to be bigger.

[Jimbo45]

You might want to move on to a 310 or cyl. These big oem cyl have proven that they can be head aches. Most that tell you different are looking to cash in on some $$ from you or others reading the thread by promoting the oem cyl use vs others 300 range and up options. Once that cast in sleeve of an oem is changed it is no more bulletproof then any other cyl and going bigger you can go beyond its designed water jacket and integrity intentions real quick. It sucks $$$ wise but maybe run your old stuff on the lower end $$ wise until you can get the cash together for something that was intended to be bigger.

Probably some real sound advice right there, and I agree.  But, I really can't go to the trouble and expense of removing the engine and sending it off to have the cases bored right now for a BB top end.  Maybe next year.  I just want a reliable overbore and correct head, that seals properly, so I can go ride with my son.  I don't care about tons of horsepower at this point.  I didn't think this was gonna be that hard.  I know, its a 30 year old bike, and I should have expected to go through some issues.

[Jimbo45]

I just wish there was someone I could send my '86 jug and head to, that would bore and true up the deck on the cyl, to 68.5mm or 69mm whichever is required, and include whatever gaskets/o-rings/spacers (if the cyl height is reduced due to machining) I may need, and lap the head, and cut it for the new bore diameter, and adjust the dome for pump gas.  I then get it back, buy a piston kit, and install.  I just don't know who to go to to trust for this, and that won't charge my first born.  I am out of funds for this project.   I will call the shop dem3500 suggested, and see what they suggest.