KZ1000 Backfires & won't stay started?

[mountainbiker]

Let me start by saying thanks to all. I have really enjoyed reading your post. I am new to the board I hope to help some one else out like I hope I get help here. So thanks in advance!

The Bike:
1986 kz1000 police bike, former Denver police bike.

The Story:
Was bought by a guy from a police auction about 15 years ago. He owned about 150 of them, and parked this one in his warehouse from the day he got it to the day I bought it. Never even started it. When I bought it about 3 years ago he cleaned the carbs, put a few new plugs in it, fresh gas, go it running remarkably enough in about 30 minutes. I rode it home! Then it got to sit for another 3 years. I did start it every once in a while but nothing significantly enough to make a difference to keep it running smooth.

Recent events:
I had the bike started ran rough but was running. Then I changed the oil, cleaned out the gas tank. Today I pulled the carb, cleaned that. Put it back together.

What it is doing:
Now I half way have it running. The problem is, when it is running I have to hold the gas on about 1500 to 2K RPM to keep it running. Now it seems to back fire a lot as well? I am not sure what to do. I am mechanically inclined, more so on 4 wheels.

Please help me figure out what to do to get it running so I can ride the damn thing! It has been sitting for too long and I have moved it with me 2 times across the country. My girl friend is just about ready to sell it when I am not looking. At least if I get it running I can ride it to work a few nice days a week.

Thanks for all your help.

Rick in ID.

[MFolks]

Check the voltage at the small wires going to the coils. This should be the same as battery voltage (with the engine off) if it is less than battery voltage then you have a problem with the aged wiring.

A website wiredgeorge motorcycle carburetors - Vintage Japanese Motorcycle Carburetor Sales, Rebuilding and Restoration - Home covers a modification using a relay bypassing the wiring. His website lists parts and wiring diagrams. Many riders at KZrider.com - Home have done this mod with results that make their bikes run better than new. Give his website a look over and make your choice.

[elr658]

First, clean the pilot jets.

[Nessism]

Originally Posted by elr658

First, clean the pilot jets.

...and while you are at it, clean the entire carbs and replace the old rubber o-rings. Dropping the floatbowls and spraying out the crud is not good enough.

[StarGate]

And if the above suggestions don't fix it, check to see if you have air leaks around the rubber connectors on both ends of the carbs but I think the pilot jet cleaning will do it.

[mountainbiker]

Ok, where do I find the pilot jets?

I hate to ask but I do not have a manual and no money to buy one right now.

Thanks again.

[StarGate]

I believe that bike has the BS34 carbs. If it does, remove the bowl and with the carb inverted, look just forward of the main jet (large brass jet in the middle) and you will see a small aluminum plug about the size of a #2 pencil eraser. Grip it with a pair of pliers/fingers or whatever and pull it straight up and out. The pilot jet is just below it, and be sure to use the proper size screwdriver to remove it. Also check the o-rings around those little plugs and clean the passages below the pilot jets as well.