1986 Kawasaki Bayou Backfiring

[ohajoh]

I have a Yamaha bayou 300, I think 1986, ran great till last year when it started to backfire a little. This year had trouble starting it up, changed the plug, and ran some carb cleaner through bust still sputtering? I adjusted the choke as it always had a problem staying running when the chock was open and now seems to be ok, but still sounds like it wants to backfire? Any suggestions???

[pete59edsel]

Possibly due to fouled spark plug, ignition timing incorrect (leads swapped around). The reason for the backfire is unburnt fuel accumulates in the very hot exhaust system and ignites there. Looks like you have tried these things...

[Ajmboy]

If it's a Bayou 300, it's a Kawasaki. Like the post above, check the plug and also check your choke operation.

* Moved thread to Kawasaki forum. Added year, make, and model to thread title.

[panthers06232]

i would check the needle in the carb or make sure your conncection from plug wire to plug is good

[shavery]

have you tried cleaning the carb and draining the old fuel and changing the plug?

[motoboy529]

Sorry for bringing back this old thread, I'm new to the sight and I'm not sure how to start my own, if I can.

Anyway, I've got what I believe is a 1986 Kawasaki Bayou 300. Apparently it had a new top end put on it including a brand new cylinder and head about 6 months before it sat. Well its hard to start no matter what, once you get it started it will idle fine and you can give it full throttle and it will run fine. Well after about a minute or so it will die and I have to wait for it to cool down until I can get it started back up. The bike sat for about 3 years before it was given to me. Before it sat it ran fine, just a rusty gas tank and some bad wiring. The wiring is fixed and I have a make-shift gas tank on it now. I took the carb off and noticed that the choke cable was broken so it can't thread in, I don't think it is a problem, maybe it is, who knows. I took the carb apart and realized I was missing the spring that goes on the end of the air screw. Is this an important part or not? Are any of the problems with the carb affecting the way it runs? I intend on replacing the broken parts after I know for sure it will run correctly. HELP, PLEASE!!!

[oxidized_black]

it almost sounds like a bad coil or a coil wire to plug is cracked. usually you have to wait for a coil to cool down before a bike will start again. not sure with the choke cable, but spring you should have to keep the fuel/air mix screw. not sure if that hampers the running of machine. when it dies, does it seem it is running out of gas or electrical breakdown?

[motoboy529]

I don't believe that is the problem because today I got it to fire right after it died, while I took it for a ride around the yard it bogged out as soon as you give it throttle and now does it when you try to start it. Since my choke cable is broken I was able to move it around and pull it out or push it in. When I pulled it out about a quarter of the way out it would idle and then die as soon as a moved it. If you're wondering where it is broken, it is right where it screws into the carb, the threads on the cable are destroyed.

Edited December 4, 2013 by motoboy529
Misplaced word.

[oxidized_black]

i would recommend trying to put a heli coil in the stripped thread if you have room. there might just be a vacuum hose or leak happening then. how clean is the carb with the jets etc ... ?

[motoboy529]

I don't believe I have enough room in it. I'll probably purchase a new cable and bowl o-ring while I'm at it. Would RVT gasket maker work for a seal? I haven't cleaned the carb since this problem has happened. It doesn't have a fuel filter so it may have a clogged jet at the moment. I'll clean it tomorrow and order the cable and o ring.

Edited December 4, 2013 by motoboy529
Not all information

[oxidized_black]

yah the rvt black stuff is good !!

[motoboy529]

Thanks to everyone's help I got it goin. I plugged the choke hole with a piece of an old rag and taped it there. Plugged another hole that was pushin fuel out the top, and got a spring for the air screw. Now it's just a matter of fixin the carb leak and adjusting the air screw a little bit. Thanks.