Rich or lean?

If my Recon pops every time I let off the throttle does that mean it's running rich?

I think it does mean it is running rich. That happens to me on my Honda Foreman when I let off the throttle fast and slow down. Probably you should call your local Honda dealer.

If you want to know how your bike is running look at the spark plug. I will try and splaine why your bike back fires.When you are cruising along their is a lot that is happening not only in the engine but the exhaust system as well.What happens is when you let off the throttle some unburned gas is now inside the exhaust system. Inside the pipe it is very hot. When the unburned gas hits this hot spot it is just burning off the unburned gas.Nothing to be alarmed about. I would have a look at the air filter just to be sure that it is not clogged with dirt that could be a possible cause, Ken

Sounds good Ken!

Thanks for the input. I will take a look at the air filter and spark plug. Does anyone know which way the mixture screw adjusts on a trx 250 recon? In other words, does turning it out making it more lean or more rich?

I do not believe it.If the bike runs well just leave the damn thing alone! If I am not mistaken it has a FIXED JET.If you want to mess up a good running bike and spend $$$ getting it repaired then have at it.The adjustment you are mentioning is the idle if memory is correct. Just ride the bike and enjoy it.KEn

What Ken said! IF its runnig good don't mess with it.

I thought they shouldn't pop all the time if you have everything set correctly? If that's the way a lot of them run then that's fine, I'll leave it alone.

the air fuel ratio will cause a backfire but improper valve settings, exhaust leak, intake leak, and ign. can also contribute to it. the easiest adjustment is the needle on the throttle valve on top of the carb. lower the needle (raise the clip) will be less fuel (leaner) and the opposite for more fuel. do it one groove at a time most likely just drop the needle one groove and leave the air mixture screw alone. plunger will go in backwards and hold it half throttle so make sure the throttle operates proper when done.

Pinetag, Has the exhaust system been modified? If the baffle has been removed then this could be a contributing factor. I do not mean to be harsh, but I do not want you to have to spend monies to have your dealer put his hands all over a good running bike.

Have you ever been to a dirt track car race?As the cars are going into a corner you will see ( especially at night) flames coming from the exhaust. This is the same thing that is happening to your bike but at a much smaller scale.Plus they have no mufflers.

If the bike is running well then enjoy the ride. What type of gas are you using? I would try a different blend. Ken

Regular 87. Do you think premium would make a difference?

My KQ runs better on 93 Octane.

So last night I went out to look at the air filter based on advice above and it was damp. It smelled like gasoline and I have driven it since Sunday. How could that happen? I'm assuming that means it's running rich?