High rpm, crankcase pressure, oil leaking

[OLDENUFF]

There is also an o ring behind your gear indicater switch which can leak oil into the sprocket cover.

[gearhead13]

80mm is a big bore. What wall thickness do you have left on your sleeves?

If you're under 1.5mm, your rings wont be liking the experience, causing blow by when the engine is under high rpm load. You shouldn't need to open the breather up, but don't choke it up by fitting too fine a mesh gauze either.

If you're getting oil on your rear wheel, make sure that the base gasket isn't still leaking.

The sleeves have over 2mm. I used gsxr sleeves that were 78mm stock. When the sleeves were fit in the 1150 block, I think that they broke through exposing a little bit of the sleeve to the outside. Then oil creeps up along the sleeve and out the part where they broke through, causing a leak. The oil seems to be coming from higher than the base gasket, but there is no leak from any gasket any higher ( head or valve cover) I had the top end off recently and put threebond around the sleeves.
The gear indicator cover was taken off when I did the shifter shaft seal and seemed fine. It has a Paul Cashio starter in it, and I am wondering about the condition of the o-ring on it or whether the Mitsuba starter is the right size to seal the opening.

[gearhead13]

Went and picked up a new starter o-ring, pulled the starter out. The old o-ring crumbled when taking it off. You think for the amount i spent on the super starter, he could have put a new $2 o-ring on it? I know I should have checked but WOW.
I really doubt excess blow by is the issue, I did a compression check on it and got 190 psi cold/dry, so it is sealing very well, up 20 psi from before I had it apart. I added a 0.010" to the 0.020 base gasket to maybe lower compression a bit as well

[49er]

The sleeves have over 2mm. I used gsxr sleeves that were 78mm stock. When the sleeves were fit in the 1150 block, I think that they broke through exposing a little bit of the sleeve to the outside. Then oil creeps up along the sleeve and out the part where they broke through, causing a leak. The oil seems to be coming from higher than the base gasket, but there is no leak from any gasket any higher ( head or valve cover) I had the top end off recently and put threebond around the sleeves.
The gear indicator cover was taken off when I did the shifter shaft seal and seemed fine. It has a Paul Cashio starter in it, and I am wondering about the condition of the o-ring on it or whether the Mitsuba starter is the right size to seal the opening.

Sounds like you you could have 2 leaks then.

I'm in the same predicament as you with my BB 850. 2 of my 1150 (2 & 3) sleeves have just broken through on the cam chain tunnel side.

Not sure how to seal this, because the ideal solution is the stock o ring, but there isn't any room left to fit one. The problem occurs due to the differing expansion rates of the steel sleeves and the surrounding aluminium. Movement allows oil to be forced through the unsealed joint. Without the break through, it would have still been trapped by the top flange and the head gasket.

[gearhead13]

Sounds like you you could have 2 leaks then.

I'm in the same predicament as you with my BB 850. 2 of my 1150 (2 & 3) sleeves have just broken through on the cam chain tunnel side.

Not sure how to seal this, because the ideal solution is the stock o ring, but there isn't any room left to fit one. The problem occurs due to the differing expansion rates of the steel sleeves and the surrounding aluminium. Movement allows oil to be forced through the unsealed joint. Without the break through, it would have still been trapped by the top flange and the head gasket.

Exactly! Someone who understands I had the top end off and put threebond around the sleeves. I guess I didnt get it all sealed. Threebond is a real pain to work with. Should have used ultra black or something Or even JB weld
You put 1150 sleeves in an 850 block wowzers If you could clean that area well enough, JB might work.

[49er]

Exactly! Someone who understands I had the top end off and put threebond around the sleeves. I guess I didnt get it all sealed. Threebond is a real pain to work with. Should have used ultra black or something Or even JB weld
You put 1150 sleeves in an 850 block wowzers If you could clean that area well enough, JB might work.

Threebond, the product used for sealing the crankcase halves might work if applied to the break through areas and the bottom of the sleeves.

I've never used JB Weld, but believe that it dries hard, so probably won't work well with expanding and contracting areas.

The cylinders haven't been fitted to the engine yet, so there are nice clean surfaces to seal at present. I'd like to choose the right solution rather than having to clean old sealant and oil from the area before trying something else.

[5150/gs]

i hAVE THE SAME ISSUE KIND OF,I RUN PODS N PIPE,
WHAT I DID WAS I GOT 4 PVC ELBOWS AND BRAIDED PVC TUBING,DRILLED 1 HOLE IN EACH POD,PIPED IT ALL TOGETHER WITH 3 T'S AND HOOKED IT TO THE BREATHER,IT NEUTRALIZED THE PRESSURE AND STOPPED 98% OF THE LEAKS,JUST MY 2 CENTS. sry for caps, too lazy. to retype.sry steve,fat fingers again