Wont start up

My 1980 LZ440 wont start up, I havent started it in a while and I tried today. Its an electronic ignition, the engine starts to crank up, wont turn over but then backfires really, like super loud like gunshot loud and some smoke starts to come out from where the carbuerrator air filter is. Anyone have have suggestions, please help.

Is battery fully charged. Electronic ignitions like lotsa juice >13v.

Yep the battery is brand new and fully charged.

Did it run OK before being parked? Also, check the airbox and mufflers for critters who may have moved in.

Nice fresh gas? Old gas may not have enough volatiles left in it to start a cold engine. Carb float bowl needle valves may be stuck open allowing engine to flood or stuck shut. Were carbs drained of fuel last it ran? Evaporated gas can leave a gummy varnish on small parts such as needle valves and fuel jets. Spider nests in electrics or mouse nest in air filter? Was it running fine previously?

Put fresh gas in. Put new plugs in. Drain float bowls and remove, check for gummy stuff. Check for cracked intake manifolds before and after carbs. After more so.

I did put fresh new gas and also no spark plugs and still the same problem. Its weird that when it backfires the smoke comes out from where the air filter is. It only backfires when I try to start it, it wont actually turn over. The last time it ran was about 3 months ago.

My 1000 was backfiring through the carbs due to dirty intake valves that weren't sealing. Did you check your compression? I know, I know, testing compression is like going to the dentist. If you have a leakdown tester you'll be able to hear where you're losing compression. Remember the three ingredients to start: 1) Fuel, 2) Spark & 3) Compression. Try removing your spark plug lead and holding it close to the block in a dark garage while attempting to start - you should see an arc from the lead to the block. If you don't, then your problem is electrical...

Good luck!

Maverick

did you cross a plug wire?

BSKZ650 wrote:

did you cross a plug wire?

I agree, it sounds like you may have crossed a plug wire. I don't know for your bike, but my KZ550 has one coil for #1 and #4 cylinder and the other for #2 and #3.
I wish you well, and hope you get it running soon

Assuming it's a KZ440 (I have no idea what a LZ440 is) it does not make any difference if you cross the plug wires, they both fire at the same time anyway

When I put the wiring back on my bike last week (without a diagram) I wired the coils backwards.

It was doing the same thing.

ran429 wrote:

When I put the wiring back on my bike last week (without a diagram) I wired the coils backwards.

It was doing the same thing.

Primary or secondary side? Did you switch the wires going from the ignitor to the coils, switch the positive and negative wires, or have the plug wires on the wrong plugs?
The KZ440 is a twin and fires both plugs at the same time, so you can't really put the plug wires on the wrong plugs.

I'm a little unclear on the symptoms, does the motor spin over using the electric starter? Does it start spinning over and then come to a sudden halt and backfire? If that's the case, then check the timing advancer under the round cover on the right side engine cover towards the front. Grab hold of the rotor and see if it turns clockwise. If it don't turn, then it's probably stuck, and probably in the advanced position.

Post edited by: steell, at: 2006/03/03 14:08