Hard to start then idles but dies with throttle

I have been riding a 1984 KZ700 for about two months.

The bike has intermittent starting/running issues for the past two weeks and now it will barely run at all.

I rode to the beach on Friday night, parked for two hours and then it had trouble starting and once it started, it backfires, runs poorly, dies on even a little throttle. I had to call a tow truck to get it home.

Any suggestions as to where to start? It did the same thing a couple weeks ago, but eventually started and ran fine again. I have a strong battery, a new starter and the bike was running well when I stopped at the beach.

John

Hi John, Check your carb mounts to the engine. It sounds as if you have a bad air leak there. Does it start and run good other times or once in a while? When's the last time you had new plugs put in, or the carbs cleaned. Another thing that should be done, is all the electrical connections cleaned, usually with De-oxit. I used Scotch Brite and chrome cleaner for the males and folded over pipe cleaners and chrome cleaner for the female ones. It takes quite a while to do this, but it's well worth it in the long run. Get the factory manual and check your coils per instructions, also the spark plug wires. It does take much to make these old bikes run for crap, not only Kaws, but other makes also. Good luck. Bob

Check for proper voltage and make sure you dont have a loose or broken wire. And check your timing advancer and make sure it turns freely. Are you running a fuel filter? might not hurt to change it if you havent for awhile.

make sure something did not get into your exhaust.
a plugged exhaust will start and idle but die when you give it the gas.

leon

I am looking for the timing advancer but my manual is for a kz750 and mine is a kz700. Can you tell me where I find it?

www.z1enterprises.com/Cam-Chain-Tensione...KZ1000-7780-370.aspx Theres one from Z1E

Powerstroke_fan - thanks, I think you're leading me down the right track.

- I have spark
- I have gas
- I have 150 compression on all cylinders (so should be no stuck valves)
- I checked for plugged exhaust (thank you Leon) and all is clear.
- I checked for exhaust leaks in and out of the carbs and it all looks good.

My manual shows the ignition advancer in the same area as the timing marks, but it isn't there - there are no springs or anything. So I am guessing that this is electronic ignition and that the ignitor box under my seat is the advancer - can anyone tell me if this is correct?

I have had wiring problems with that harness twice already - once it was the fuel gauge wire and the other time it was the start wire running from the handlebar switch to the solenoid. I am guessing that the problem is in that harness somewhere, but if I can't find it, does anyone know how to test the ignitor before I spend $200 on a new one?

John