Burning oil after rebuild, BAD!

okay so i just finished rebuilding my 83 kz 750, new rings, gaskets, and valve-train etc. Put the motor in the frame and fired it up, the bike is now the ultimate mosquito repellent, pretty obvious its burning oil. It burnt oil a little before but nothing you wouldn't expect from a 30 year old bike, now after the rebuild its bad, I would never ride the bike like this. I have no idea what I did wrong, took my time did everything by the manual and now its worse ha. any ideas for trouble shooting would be greatly appreciated. The head gasket is a new versah gasket, maybe thats the issue? I didn't replace the o-ring gaskets on the the left and right side of the cylinders just re-used them. I cant imagine its the valve stem seals replaced them with new viton seals and the rings are also new oems. Any ideas would be helpful thanks!

Sorry to hear about your issue.

1. what was the piston gap / relative to bore?

2. what was the ring gap set at

sounds like oil is getting by rings to combustion chamber. could be a mathematical issue bases on two variable's above.

my 1105 Wiseco piston to cylinder clearance was set to 0.0020 or (0.051 mm) per factory spec.

What did the cylinders look like?

Piston rings installed upside down maybe pushing oil into the combustion chamber instead of down into the crankcase.

oil rings over lapped it happens to the best of us.

Or maybe broke an oil ring. I am ... I mean I know an idiot who did that once. :lol:

Maravinchi wrote: okay so i just finished rebuilding my 83 kz 750, new rings, gaskets, and valve-train etc. !

Cylinder wall hone? was bore measured to see how much wear it had?

Sounds like either you have a broken/screwed up ring or the rings just can't seal at he cylinder wall.

Maravinchi wrote: I didn't replace the o-ring gaskets on the the left and right side of the cylinders just re-used them.

Have you ever heard the phrase "Penny wise and pound foolish"? Penny and Pound being used as in English currency.

Those rubber rings are the seal between the oil pressure and the cylinder. I'd have replaced them.

DFIGPZ wrote: oil rings over lapped it happens to the best of us.

x2 Have someone hold a piece of cardboard a few inches from the end of the bike and rev it a few times. If you see oil droplets on the cardboard you can rest assured you probably overlapped one or more oil wave rings. If they're Wiseco Pistons it's pretty easy for that to happen to the inexperienced DIY engine builder. No shame in it. As DFIGPZ said....it happens

Remove the plugs and see which cylinder it is. Most likely only one is doing all of it. Besides the aforementioned oil ring expander over-lapped. It could also the end of the expander broke off, or the oil ring/s itself got tweaked/ bent on install. The two small oil rings also need to have the ends staggered so they don't provide a place for the oil to travel through. They're a delicate item for sure. An extra pair of good hands to help with the re-assembly May be whats needed.
You can probably pick up one pistons worth of rings on Feebay,
Good luck.

It's been awhile since I've worked on this bike got frustrated and went on to other projects. But recently picked up where I left off...thank you for all of the suggestions, I took everyone of them into consideration as I was carefully diassembling the top end. After lifting the cylinders off first thing I checked was the oil rings, only to find none of them were bent, broken, or overlapped...is it possible they were overlapping in the cylinder but after removal fell back in place??? Checked all rings and everyone of them was staggered correctly also checked orientation of compression rings, top ring does not have an indication mark or a bevel and the 2nd ring has the n mark facing up...cylinders look good have cross hatching, cylinder bore on all four measures between 65.65mm and 65.82mm..measured with vernier caliper...manual wear limit is 66.10mm....ring end gap on top ring .37mm... 2nd ring .29mm manual indicates .2-.7mm....so idk everything checks out I still have no idea why it was burning oil so bad....I appreciate all the help I've been given so far, any other suggestions on where to go from here?

Thank you

How many miles since the rebuild? Did you use a mineral oil? Running-in rings is a controversial subject but imo you need to load them up a bit.

I guess bad valve guide oil seals would be particularly bad if started from cold and left on the sidestand. My GSX11 used to smoke a lot if unused for a few weeks.

Wouldn't overlapped ring gaps rotate out in time?

I think honing surface finish is critical and often not done right with these DIY honing tools.

What are your compression figures?