Is my Kat dead?

[Danhutch]

Hey there riders, just got off the phone with my local motorcycle garage, only to be informed that they think my motor is 'shagged' apparently once they had it started it began to billow smoke in their workshop.

Now, im not ready to give up just yet, the bike has sat for nearly 2 years and was seized when i began work on it. could it still simply be burning oil and whatnot from my attempts to unseize it.

If anyone has had similar smoking problems from their kats i would love to hear from you as im not willing to drop mine in the trash just yet.

[92xjunker]

Plus be a multiple of thing that would cause that smoke, rings, head gasket, valve guides or more major issue like cracked head. Either way it can be fixed. The easiest way to fix it would be to swap in a good used engine.

[Danhutch]

ive been looking, engines near me seem to be a bit scarce, however, would a slight oil leak from the engine lean towards a gasket or crack?

Plus be a multiple of thing that would cause that smoke, rings, head gasket, valve guides or more major issue like cracked head. Either way it can be fixed. The easiest way to fix it would be to swap in a good used engine.

would the only way to narrow this down be to take the head off?

[92xjunker]

Yes and yes
Compression test would also be needed.

[Danhutch]

i assume a compression test would narrow it down too right, would it be better to do this before taking the head off?

[Danhutch]

Ok so, compression tester ordered from ebay, time to do some research on leak down testing too, not letting this kat die im assuming from the 10.7:1 compression ratio my ball park psi is 155-165, could someone confirm for me please?

[92xjunker]

Grab the manual from here. You'll need more specs. http://katriders.com/vb/showthread.php?t=138096 I'd guess that the rings are stuck and/or the cylinder walls are scored from the rust inside. Been there. New rings and cylinder fixed that. Not to bad in price either. http://katriders.com/vb/showthread.php?t=134329

[Kreylyn]

Common... but minor issues... that would cause the bike to smoke.

fuel in the oil
oil in the exhaust
excessive oil in the airbox

With the exception of changing the oil if it's contaminated, most of those are just... clean and run it till the smoke stops.

Compression test needs over 90, but with in 20% of each other. So 4 90s is fine. 3 145s and 1 90.... not so much.

Krey

[Danhutch]

just for my own info would this engine http://www.ebay.co.uk/itm/1998-1999-...0AAOSwXYtYvIny

be a straight swap as far as the engine mounts go?

[92xjunker]

No, that is water cooled. To get that in would require major work.

[Danhutch]

anyone know of a place that i can find piston rings to fit my bike? ive been looking all over the place and struggling to find anything, would piston rings from a different model fit my bike? (1989 gsx750f)

my manual tells me i have a 73mm bore

[AR-15]

Lots of good answers here. I have seen stuck rings clear up on their own, over a few hours use. And someone mentioned "oil in the exhaust" that two might clear itself after a while.

[shpielers]

Bikebandit and ronayers should have rings

[Danhutch]

HOLY *!#Ž£ i didnt realise piston rings were so expensive, any ideas for something i could pour down the cylinder to attempt to free up the rings before i spend almost 150 pounds on 4 sets of rings?

Also i live in the UK so ideally id like to find some from over here to avoid silly shipping costs

plus there is 100% oil in my exhaust, is the only way to remove this to run the bike?

[thehiddencheese]

fuel in the oil
oil in the exhaust
excessive oil in the airbox

With the exception of changing the oil if it's contaminated, most of those are just... clean and run it till the smoke stops.
Krey

Krey listed everything to do