Topic: 1970 cb750 forgot to install 4 large red jugg o-rings on my top end build

[RayWrangler]

hey guys, ive done it again.


i forgot to install the 4 red jugg o-rings that go on the bottom.

got it all put back together. think its a big deal? this motor fought me like no other, im kinda done with it.

i pulled the old ones out, slipped my mind to put the new ones in


anyone else do the same? what issues am i gonna be looking at ??

what a bummer


oh just to be clear, i put the wiesco 836cc kit with kenny harman D camshaft and CR29 carbs

from reading other posts it seems like with larger bore juggs the stock o-ring will not fit in and some guys run without them. also i used coppercoat on my base gasket.

thx guys

[Tews19]

Are you talking about the cylinder o rings? I must admit I did this on my 550 605 build. I was told I will get a head gasket leak within 500 miles. I will report back once I hit it.

[bjbuchanan]

Over time you may weep but screw it. You will never experience large leaks because they are no pressure situations.

If you are really fed up, go for it. I'm sure plenty can identify, myself included. If you are Hell bent on perfection I gguess you would have already known the answer anyway

[PeWe]

If you have to fix it. Do the frame kit as 754 has constructed. Just pm 754. There is a thread about it including where to cut. I recommend how I cut, also in that thread.
You cut the frame and re-mount that part with maintained stability. Then you can remove valve cover, cam, head and cylinders without pulling the engine and all stuff you have to remove and oil to drain to make that possible.

I have it and could do some extra job several times only this year, change cam is a rather quick job nowadays. Including retorque head.

[RayWrangler]

thx guys.

research i have found of the larger bore kits and sleeves make it impossible to run stock sleeve orings, i guess 1 guy did cb900 orings instead. and some other guys just dont use them.

i may just have lucked out on this one.

pewe good thought, im not the kinda guy to cut a frame.

[PeWe]

I fully understand that. I could not cut the frame before either.  But now I recommend it!
I became practical earlier this year when I had to pull engine after I had recently mounted it. Fresh paint on engine and frame. It is not visible unless the tank is removed

My bike is not an exact OEM CB750 either when it's tuned. I'll try different cams which is fun.

If my bike should be in perfect OEM CB750 museum style, frame shoiuld not be cut.