[Maiku]

Not sure what's going on here, but quite frequently, especially at 50+mph it bogs like no tomorrow. Not just bog, but kicks and bangs. I'll just be driving steady and it starts bucking like a horse. I just bought this bike not even a month ago. The guy I got it from said it was tuned up a short time ago. So I'm not sure what it could be. Help is appreciated greatly.

 

[twowheelertoy]

EX500 Twin Cylinder Umm

Me thinks the first thing i would do is replace the Spark plugs, You only need one to play up and the power loss is quite noticable.

The back fire would be caused by the spark igniting all that fuel still being drawn in whilst the plug was intermitantly not firing.

Try that if you get no joy i'll think of something else. :idea: :idea: :idea:

 

[Anonymous]

50+

Have you cleaned or changed out the airfilter? I would also change out the fuel filter. Check the plugs when you pull them out so you might see which side is causing the problem...get back to us on the answer.

 

[Whitey]

Gainesville, huh? Howdy neighbor. I agree about the plugs if it was just bogging down I would suspect possible fuel filter or other fuel restriction but the backfireing sounds like plugs bad.

 

[ZX-2R]

fuel

Somehow we missed dumping what ever is in the tank and using fresh fuel. to flush hte carbs you can pull the drain plug and open teh petcock shortly...till both have been done...then try it...and let us know...

 

[Freakinout]

Basically I'd replace the plugs, empty the carb bowls, and fuel tank and go with some fresh gas too. You might run some carb cleaner (B-12) through your gas too. Just don't get any B-12 on your paint. More than likely your not getting sparks. The cables might also be a problem.

 

[parky151]

I am having a very similar problem with my 88 EX500. I was riding it on the highway when all of a sudden it started backfiring and bucking n stuff. I tried to get it home but it didn't work. As you are sitting on it, the left cylinder is firing but the right side isn't. I asked a couple friends and they recommended replacing the coil, and $80 and 2 weeks later I had one ready to install. After putting it in, it still won't fire. I'm at my wits end.

 

[Lawn Masters]

plugs AND wires are a way to fix this possibly. I went through it on an 86 Toyota and it only took me the money to buy wires and plugs for it. its relatively cheap, and normally the culprit. dont ALWAYS suspect the coil bad when its not firing.

 

[kerNol]

My buddy is actually having a very similar issue with his 87 EX500, once it warms up it starts to bogg/miss and run rich. Nothing has been done to the bike recently this problem just began to occur the other day after he ran the tank so low he had to switch to reserve and then forgot he left it on reserve after fill up. Needless to say after going back to the regular on position for the fuel he rode around all day and now picked up this issue. Any ideas? I'm thinking maybe a fouled plug or perhaps a stuck needle, although im not sure why it only happens when warm and only below 4500rpms, above that it clears up.