monster 795 gets backfire with termi exhaust

[songau]

I live in VIETNAM.

My friend's bike : ducati monster 795 which is manufactured in ThaiLand.

he installed DUCATI MONSTER 795 TERMIGNONI CARBON SLIP-ON EXHAUST
[96460312B] ,
 link:http://www.store.commoto.com/ducatistoremonster6967961100exhaustsystems-ducatimonster795termignonicarbonsliponexhaust-p-1199255.html

he bought it from Commonwealth Motorcycles in USA.

His bike gets some issue after installs that Termignoni exhaust:
- odometer goes wrong .  it increase 40% with other
- there is backfire when i throttle down

would you give us some advice.

[Slide Panda]

That kit comes with an ECU - ensure it's displaying Miles not Kilometers. A sudden 40% jump in the odometer reading is probably due to it changing it Kms

For the popping - there's probably a leak in the exhaust. Re-fit the slip-on cans and ensure they are sealed well. Some exhaust sealant can be used to help make sure there are no leaks.

Popping on deceleration is a common symptom of a leak, and with the fact that you/he just changed out the slip-ons I'd lay good odds to it.