BackFiring.

[OB_byhalia]

What causes this to occur?

Nothing but 93 octane used.

 

[OB_asubayah]

Mine used to backfire also. I put some slip-ons & modified the baffles and then had the bike re-mapped. No more backfires.
maybe yours is a bit lean?



[This message has been edited by asubayah (edited 01 September 1999).]

 

[OB_KawAbuser]

Backfire ? If a bike is lean why does it backfire, if there is unburnt fuel in the residual gases in the exhaust pipe why would this be a lean condition (lean being less gas). If it was rich wouldn't there be more unburnt fuel in the pipe?

Frank will you explain this.

 

[OB_Yngve]

If an engine is way to lean it will backfire. This is because its so lean under trailing trottle that the mixture will not ignite inside the combustion chamber. It just go out through the exhaust valves unburned. Out in the exhust pipe(s) its exposed to very hot metal wich in turn ignite the mixture and U have a Backfire. To stop this some injected engine has a fuel cut out that doesnt deliver any gasoline on trailing throttle ( over a certain rpm ) so there is no backfire ( until you go under the preset rpm where the gasoiline is injected again ).
I hope this was understandable ( damn its hard to think in one language and type in another ).

 

[OB_VegasDude]

My wife thinks in one language and bitches in another.......it seems easy to her.......

 

[OB_KawAbuser]

So if my fuel filter(cut out problem)is plugging up intermitently could the fuel filter be added to the backfire when off the gas? If the filter is creating an overall lean condition.

 

[OB_DRAGBIKE_dot_COM]

When is it backfiring? Under acceleration, decel, cruising?

 

[OB_KawAbuser]

an occasional pop when backing off the throttle, entering corners, on brakes, just basically when you chop the gas to change direction or grab brakes hard. But bike has been running wierd, sometimes great and other times blubbering around 6000 rpm. When running good it runs great, clean and crisp throttle response. When running cruddy it seems as if it is not getting enough fuel ands doesn't clean out. After the bike has a cutout or a blubber, when it cleans out it runs its best. I seems like a change in fuel pressure. What is really strange is that it will stall at low speed when on the brakes(slowing for a stop sign or signal light)

 

[OB_byhalia]

DragBike DC,

Mine backfires only on "decel". This problem did not occur before I drilled the baffle plate inside the stock exhaust cans (which proved to be a favorable move, sound and performance wise).

Also why are the dealer service departments still lying about valve adjustments necessary before (the owner's manual mentioned) 15,000 mile service?

Thanks for any assistance.