White smoke 2008 Gt250r carbed

[Josh]

1. Hey so this is my first post on this forum since I can’t think of anything else and am deciding to see if anyone else has had or has this problem. I got the bike with “carb issues” it ran but misfired and a lot of white smoke would come out of the exhaust after warming up and upon revving the engine. I deduced it down to burning oil in the cylinder and replaced pistons, piston rings, and valve stem seals for both cylinders. In the process of the engine rebuild I deleted the egr in hopes of saving space and helping engine possibly. After putting the engine back together with everything torqued and properly installed I started it and noticed a valve cover leak. The engine still smokes a lot and I’m wondering if the tube that was for the egr also doubles as a pcv valve. Since I replaced the rings and valve stem seals the only way that I know oil can get in the system is through blow by with too much pressure in the crankcase forcing oil past the rings into the cylinder. Please help if you can and I can provide additional information if needed to help diagnose this issue.

[Simon]

If you have left the one way valve block in line then the crankcase cannot vent, at the back of the crankcase is the vent pipe that goes to the valve just remove from the valve & vent it to atmosphere.

[Josh]

I’ve tried venting the hose that connects to the rear cylinder to atmosphere but the white smoke is still there and I get exhaust fumes out of the hose as well any suggestions?

[Simon]

When you remove the hoses from the cylinders you need to fit a blanking plate over the hole in the cylinder, then look towards the back of the crankcase on the left hand side you will see where the hose comes out of the crankcase that’s the one to vent to atmosphere.

[Josh]

Ok thanks I did that, I took it out for a short ride afterwards and when I parked there was light smoke coming off the engine from the heat. I think it could be running lean since I got higher end air filter or could possibly be smthn else?

[Simon]

Smoke off the engine is likely just to be residual oil etc left on the casings from when you rebuilt it or there’s a leak somewhere, check the sparkplug colour to see how the mixture is.

[♠️ M77]

Josh wrote:

Ok thanks I did that, I took it out for a short ride afterwards and when I parked there was light smoke coming off the engine from the heat. I think it could be running lean since I got higher end air filter or could possibly be smthn else?

Quote

i would also look to change the jets as “more air” = lean mixture , engine overheats , could burn oil as piston rings can only tolerate so much.  There is a jet tutorial on forum if you have seen it ?

As for crank smoke , go with Simon’s comments

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