Project 1992 Kawasaki ZXR250C

I need an opinion before I continue with this bike. Engine oil capacity is 2.6L, I just drained over 4L of mostly fuel. Doesn't look good. Should I do a leak-down test before deciding whether to continue with this bike or send it to motorbike heaven (aka Chris' place)?

Another job for the day was checking valve clearances. Most of the intake valves are alright but every single exhaust valve is too tight. Minimum 0.20mm and most of them are 0.15 with one or two even worse.

On the plus side I've now got a completely rebuilt set of carbs. I stripped them down again and split them apart to replace all the o-rings in the fuel and vacuum lines joining the carbs. They then got another blast of carby cleaner, double checked the float levels, and replaced the JIS screws on the bracket holding them together.

 

Thanks. I'll keep going with it then. Having that much oil/fuel in the sump probably also explains why it wouldn't rev at all when I did have it going.

@Linkin Cam chain is within spec at 127.5mm over 20 links. Tensioner looks alright as well, not sure if there's a specific check to see.

 

Yep got the whole kit. Needle and seats, main and pilot jets, air/fuel screw, choke piston, inlet needle, o-rings, bowl drain bolt. Pretty much everything but the float itself and the diaphragm.

 

I'm just about to call it on this engine. Looks like a high probability of a bad valve or piston ring.

I went to start it again this morning after having it running yesterday and about 400mL of oil has mysteriously disappeared. So I topped it up again and it took me about 15 minutes to get it started. Once started and warmed up a bit it runs and revs alright but there's a lot of air coming through the engine breather into the airbox, and it's still dumping fuel into the oil.

Just waiting for a 10mm adapter for my compression tester so I can see who the culprit is. Either way I don't have that much of an attachment to this bike so not planning on forking the money out to fix it. Will probably be parted out.

 

Hmmm I'm not sure what to think. This is the exact same issue that it had before I even touched the carbies. Now they have been fully rebuilt with new everything that I can purchase and it's still showing the same problem?

The petcock is ruled out because I'm completely bypassing it and pouring fuel straight into the carbies with a funnel. The fuel level in the line seems to hold ok and it's got brand new float needles and seats. It only seems to get fuel in the oil when it's running.

At this point I think I'll still go the compression test route before spending any more money. Would be good to know the condition of the engine anyway.

 

Will do. The funny thing is once I get it running it goes fine and doesn't seem like it's missing on a cylinder.

@kiffsta has just couriered a good set of carbs so I can test and rule that out. Compression tester adapter is on the way so hopefully I'll know a bit more by the end of the week. I've got Friday off work so will get stuck into it then.