Kz900 sitting for 10 years

So the bike is clean and will start but I don't want to run it long distance until I've cleared everything up.

I've already cleaned the carbs, tank and put in new file lines with filters.

It's got some wiring issues that I'm sorting out and should have that done in a out a 1-2 weeks.

Right now it's showing about 100 psi in each cylinder. I know that's low but I'm hoping its just because it was sitting for so long. I changed the oil. I plan to check the valves after the electrical is sorted.

My question is...

If the rings are stuck from sitting is there way to loosen things up without opening up the top end?

I have started the engine with the air filter off and sprayed a whole can of wd 40 in the ports while the bike is running.

I would put some light oil in the cylinders while the bike is sitting. I think you will be alright with that pressure. It more than likely will come up after start up.

The wd40 thing is a good idea. What kind of oil is good to pit in the cylinders? just regular engine oil?

I would put the lightest oil in I could find.

What about two stroke oil? I was thinking that since that is meant to burn it might be good plus it's really thin

Put a bunch of Marvel Mystery Oil in the cylinders & let it set a week. Before you start it take the plugs out & spin the motor over to blow out the excess oil. Start it up & ride it, it should loosen it up. if that dont do it plan on taking it apart. It will smoke like crazy for a while but if that dont do it I dont know what will.

I wonder if using Kroil in place of the Marvel Mystery Oil would work if the Marvel doesn't free the rings? I don't know how well it would burn when you start the engine or if it would have an adverse effect on the motor oil. Ed

I used Marvels on my engine that sat for 20 years and I'm closing in on 10,000 miles with no problem.

The nice thing about Marvels is you can add it to the oil or the gas with no ill effect,
that's what it is, an additive.

JD

maybe stomp on it once in awhile for short bursts too

Can a bike be ridden any other way?

trianglelaguna wrote: maybe stomp on it once in awhile for short bursts too

Your question was you were not comfortable riding it on a long trip ?
So don't !
If your ride now is around the block,
keep working on it,
ride a little further next time,
And so on and so on,
Just keep working and one day you will be able to go wherever you want too.

SeattleKZ wrote:
Right now it's showing about 100 psi in each cylinder. I know that's low but I'm hoping its just because it was sitting for so long. I changed the oil. I plan to check the valves after the electrical is sorted.

My question is...

If the rings are stuck from sitting is there way to loosen things up without opening up the top end?

Was this compression test done with it warmed up, and the throttle wide open? If not this will be a low reading. Also altitude will play into the reading, so are you much over sea level?
There are some combustion chamber, De-carbonizers on the market. Such as the Mopar Combustion Chamber Cleaner, from the Chrysler parts department.