Flames coming out of exhaust pipe

[Richard Dziak]

If the F1000 GSXR is shooting flames out of the exhaust on downshifts, what is this signaling?

Is this normal for these engines?

Advise your thoughts, why this might happen.

I have noticed this quite often on Formula Mazda's.

Thanks......

[PrivateSoftcore]

Flames shooting out is just unburnt fuel igniting on it's way out of the exhaust system

[carnut169]

I've got my exhaust directed at the bottom of my rear wing (maybe the increased airlow helps?) and the wing is black by the end of the day... when running the car in the garage recently I noticed the flame you are refering to. Rev it up and then an immediate lift and out comes the flame.

Formula Super's Haybusa also shoots fire.


Looks cool, IMHO.


Check out this photo: (it does clean right off)

[Paul LeCain]

I'd protect the bottom of that wing, somehow. I've had the aluminum (I assume that's what it is) get brittle, crack, and fail from an exhaust flow that looked just like that.

[HastyHorn]

Many of the AMA SuperBike engines do the same thing (flames out of exhaust on decel). Also most of the MotoGP bike engines do the same thing..although now that they have fuel mileage constraints they are doing it less.

Are you a fuel injected engine or carbs? Where do you have your idle set?

Hasty Horn

[Tom Sprecher]

You did a nice job on that trailer.

Bonus! If flames shoot out the pipe you don't need to paint them on the car like you were talking about doing.

Let me know if you want a ride tomorrow.

[carnut169]

Thanks Tom. I think I'll drive over there so I can make an exit if things start to get drawn out... It's right down the street from the old place, right?

Call me later when you get the chance.


Do you think that I'd be better off putting a piece of adhesive heat stuff on the wing or deflecting the exhaust away from the wing?

My concern w/ the adhesive is that it would slow the air going under the wing causing it to be less effective...

[Stan Clayton]

Sean, the original exhaust hit our Ralt FA rear wing the same way. The wing has a thin sheet of aluminum pop riveted to the underside to protect the composite. It's easily replaced should it become brittle, yet smooth to the airflow. Stan

[Mark H]

On an injected engine at WOT the injectors are full on (not pulsing) anymore, so I would suspect that when you snap off the wha peddle some waist gas is being spit out causing flames. Any burn in the exauast is waister energy but the flip side is to run leaner and maybe not have enough fuel?

A Mazde rotery engine is the worst when it comes to waist gas, on a street car RX7 the had to use 3 cats to clean it up enought to pass smog tests and finaly pulled the old rotery off the American market for emissions reasons. But it will help when your tucked up under a FM drafting him and he brakes at the 300 (no engine braking) and you want to go to the 100, saving you from knocking the nose off your car.

[glenn cooper]

OOps, out of practice

[glenn cooper]

Flames - all good, no problem.
It's the last bit of fuel that gets metered in, but throttle is closed and unburnt bits (Burnt Offerings!) go out the pipe as flame.
Sean O go for the deflector. Remember to "Keep it sano" - Motocross Max MXA 1975

GC