Air Filter Burnt

[U_h0rnet5]

Hi could anyone possible tell me why would an air filter get burnt?

Thanks
Ciaran

[parby81]

well if you happened to get a nasty backfire at some point then that could possibly burn the air filter. How burnt is burnt? Is this on the engine your stripping down?

[cargo]

Cant imagine how it would get burnt ...................A back fire is fuel burning off in the exhaust..........................

A photo might help...................

[U_h0rnet5]

How burnt is burnt? Is this on the engine your stripping down?

Kinda its my new bike that I bought, been sitting for a very long time so just going to give it a service and some new fuel which should hopefully sort out some of the bugs.

Cargo pic for ya below also it has melted the cage bit where the filter goes on!

[parby81]

on older cars if the timing or firing is 180 degrees out then you get the flames coming out the top of the carb as it is igniting when the inlets are open. Now the timing on our bikes is fixed, but maybe if someone had connected the coils/HT leads incorrectly this might occur. But i stand to be corrected on this.

[cargo]

Maybe someone tried to clean it with petrol and then dried it in the microwave ? ? ?

Even if a flame did blow back out of the carbs it would be a quick flash can see how it would be enough to do that...............

Certainly needs replaced

[U_h0rnet5]

Parby - My boss was telling me about the old cars and his kart backfiring like that, as if it would be running very rich. Well the ign. coils are the same as my other two bikes.

Yea definitely needs replacing

[kawaman]

Backfire is combustion going back through the intake line, it is often confused with missfiring producing an exhaust post-combustion, but has nothing to see with it!
I think this is the only way to burn your filter like this, backfiring may be produced by inverting the coils (1/4 coil connected to 2/3 command wire, and inversary) but I am not sure if it can burn the filter like this since the engine would only idle but not rev, the other possibility is having the intake valves not completelly closed during firing (valves adjustment, wrong timing, valve seat damaged etc).
I think you should have a look to your valves...