backfire

this is after a custom fuel map. any ideas?
guy said it could be normal operation but i dont think so.

Power commander works fine, but for better results look at the TuneECU thread. It is like tune boy, only more features, more user friendly, better tech support, more KTM maps, and best of all, its FREE!

EDIT:spelling.

that backfire is nothing compared to some of the videos that (i think it was klink) released on Youtube a while back

I also want backfire on my RC8 this winter, warm feets are always welcome

Outlet valve that's closed to late, this happens often on race preped bikes with longer timing.
Check Your valve clearance or keep it that way if you want to scare the hell out of cardrivers in the dark

Logic....
If it wasn't there before the mapping.....
Try running it on original map. Also check connectors, to do a dynorun the operator should disconnect the SAS as mentioned above. If he hasn't done this it's trouble.

the backfire was worse before i took it to the dyno guy. i think he did a shit job as well i have an exhaust leak at the flange on rear cylinder. now to fix it...any volunteers?

i will fix the leak then .. check the mapping....
just got off phone with dyno guy. he said he blocked the fresh air pump when he did the fuel mapping. he was not familiar with the acronym SAS..... he said he pinched the tube off when on dyno but did not disable it from functioning did he do the right thing??????

If you got the parts manuals with the bike, look at the secondary air system diagram in the engine parts manual. Then you will know if your bike still has that system and maybe can figure out what exactly your dyno guy was pinching.

found out there have been 3 recalls on this bike...one of them is re-tune the factory ecu, the other is oil tank/tube port diameter and check torque on a nut /bolt.
told mechanic about this backfire issue and have decided to take the expensive route and just let them fix it while they have it. let u know what they do and the results.
thanks again for your responses.

If they re-map the ecu your custom map on the PC3 will be worthless anyway!!! (the custom map builds on top of the standard mapping, if the standard mapping parameters have moved then the custom map information is worthless)

the one guy at ktm said to remove the powercommander and use tuneboy or other things to reprogram the factory ecu and eliminate the power commnader. make the primary map perfect and no need for a secondary map .... is this correct?

Yes, changing the map straight in the ECU eliminates possible problems with external factors.
Like RED ZX said, take a look in the . Many very happy customers there. Why? Because it's great and FREE!