Kz305 interference engine?

Try turning it over with your hand over the mouth of the carbs and see if it gets wet with fuel.
Steve

Will do. What would this indicate if the plug gets wet?

Your hand. It will also force suction through the venturies possibly clearing them. Do it with the choke off and WOT.
Steve

Did the hand thing. Got gas. Re assembled. No start. I do get back fire from the exhaust though. Time to check the float level or disassemble the carbs?

Check for spark.
Steve

First thing I did. I've got spark. It's blue and looks good.

Going to try and replace the spark plugs tonight. If that doesn't do anything I'm taking the carbs out and checking the floats. Maybe they got stuck when I was handling them ? Might try putting gas in the cylinders first as well and see if it starts.

As far as I can tell the back fire is because of a lean condition because of the lack of fuel.

Really want to get this thing started as I really don't want to purchase another bike until next year and if I don't get this one running I'll have to go a whole year without riding.

Might try putting gas in the cylinders first as well and see if it starts.

You might try draining the carbs, then spraying carb cleaner or starting spray into them. Just a few seconds of running will tell you whether your ignition is probably working right. Don't make too much of a habit of this -it washes oil off the bores. But it is a good diagnostic.

It is best if you can to do things one at a time, then tracing any problems afterward gets easier. Unless you had it running after the carb service your problem could be either or both the carb or top end rebuid. A clear U tube manometer test will confirm your float fuel levels.

Another thing, when you did your rebiuld, did you accidentally move the ignition timing plate at all? The coil connections under the tank to the plugs and ignition box can cause problems: a fat blue spark in open air might be marginal under compression. The ignitions do like a decent battery voltage to work, maybe recharge the battery and try bump starting it? And some fresh fuel, it goes off after months of storage.

I have a brand new battery always on a charger.
The timing plate was taken off for the rebuild but I put it back to where I'm sure it was before.
The fuel is from last year. Going to be draining the carbs and tank and get fresh fuel.

I tried spraying break clean in the carbs to start it with no luck. Might try some starting fluid though.

As far as I know the coil connection are good. Nothing looked bad.

I tried spraying break clean in the carbs to start it with no luck.

Makes me think this is more an ignition fault, if you have the sparks maybe recheck your ignition timing. You can even strobe it off the starter motor cranking in a dark garage.

I had a bike built from a bare crank up, did everything and about a dozen bikes grafted together...it wouldn't start. I triple checked everything over several weeks. Out of desparation and having done everything logical I just started rotating the timing plate whist cranking it. It started. Problem was I used an earlier ignition plate on a later 550 motor and the timing mount holes were in a slightly different place, even though it looked just right.

Checked float level. It's good.
Tried starting fluid. No good.
Only removed the air filter and sprayed in with wot.
Compression is good.
Re checked mechanical timing. It's good.

When I took the point plate off I forgot to turn the key off and it sparked and made the left cylinder back fire. It scares me and was very loud.

When cranking and it backfired a little I'm getting black smoke from the exhaust continuously.

Going to check iginition timing with a test light Monday and I'll be buying new plugs today although the old ones spark and I think they should still work.

Do you have one coil or two.
Steve