Backfiring

[mingrelian]

I've just removed the cat on my 1150 GS, which has considerably improved the torque. On the other hand, it now backfires fairly spectacularly. My BMW dealer tells me that's normal on a GS with the cat off. Is it? I have a feeling it backfired before, but the cat muffled most of it. Would it make any difference if I fitted an aftermarket exhaust?

 

[shuck raider]

More than likely a poor seal somewhere, bung up the joints with some B&Q silicone sealant, worked a treat for me

 

[Septic]

I had the same problem with my R1100GS
its got a lazer race can on with no cat it was backfiring
a hell of a lot so i got my local bm mechanic to ballance
the throttle bodies its loads better but it still does it sometimes.


stevie

 

[mingrelian]

Thanks guys. Balancing the throttle bodies was mentioned by my dealer. The bike's just been serviced, and I presume (?) that's been done. I have to say the backfiring's not that frequent - mainly on 2nd gear overrun - but it is very loud! I'll give the joints a go and see what happens.

 

[phil adams]

backfiring

done the same myself and i get all the backfiring you have mentioned. its been looked at by dealer, no leaks, throttle bods balanced, still does it. dont worry about it!!

 

[Noel]

Sealing the exhaust system will increase the backfire noise, as far as I know they all do it when they have a de-CAT on balancing throttle bodies will help, only answer is ignition re-map.

 

[mingrelian]

Thanks again, guys. I think I'll just stop worrying about the racket and just enjoy the bike as before!