Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 998 / 996 / 916 / 748 > Funny noise - ???

[Rick]

My bike is a 996R and sometimes when I let go of the throttel or slow down quickly I have a backfiring type sound, BUT its not from the exhust, It sounds like at the front of the engine is sucking in air loudly. I cant explain it, it makes a funny noise but doesnt sound like motor noise more like compressing air ???? Doesnt always do this and ONLY when deaccerlerating never when accellerating.
maybe my desription is no help to all you gurus out there, but I cant explain it any other way
Anyone have a clue what it could be as I dont lol

[Ray]

It could be "spitting back" in to the airbox. Nowt to worry about too much me 998 does it occasionally.

If a "backfire" comes out of the exhaust, you might like to think of this as "frontfire" similiar effect just a different end!!

Ray.

[BDG]

Sounds terminal to me, better sell it quick, i'll offer you £250 cash now

[Jools]

Do you feel a little 'click' through the throttle at the same time? If so it's probably the spitting back that Ray talks about 'cos it gives the butterflies a little jolt on the way through - did on my ST when the low down fuelling was out (running too rich I think)

[rockhopper]

My ST2 used to do this. I worked out that what was happening was that the throttle butterflys were not perfectly syncronised so fuel was pooling on the back of one of them becasue the injection system thought they were still a little bit open when infact one of then was shut and one was very slightly open.
The cure was to reset the tps and balance the throttle bodies.

I don't know if i came to the right answer but my adjustements certainly cured the problem.

[TP]

Originally Posted by BDG

Sounds terminal to me, better sell it quick, i'll offer you £250 cash now

No Rick, he's a scammer!!!!













How about £251?

[Rick]

I couldnt take SO much for it as it is an ENGLISH bike, I could take more than 140 GBO, too bad guys you missed out on a bargain.
Thanks guys, I NEARLY sold it to TP

[DEMON]

Its running lean on the over run, this could be due to air getting somewhere it shouldnt.
Do you have the sensor plugs in the exhaust which ducati uses for testing? check that they are still in place...not this? then check for air leaks, butterflys synch etc.

[Rick]

thanks guys

[TP]

Originally Posted by Rick

I couldnt take SO much for it as it is an ENGLISH bike, I could take more than 140 GBO, too bad guys you missed out on a bargain.
Thanks guys, I NEARLY sold it to TP

Ooh, I nearly had a 998R and a 996R!