Back firing

[Doc]

Ok so the 1992 Ducati 900ss was running good, no problems with a stage 1 jet kit, K&N filter and my old beat to piss D&D pipes...

So I get NEW D&D pipes, install them and now I have back firing, sounds cool at times but is getting annoying.

I have my ideas, what are yours?

[duey]

does it only backfire under decel/engine braking? if it does the same thing happened to me, turned out to be an exhaust leak. Missing a copper plug on the bung on the exhaust pipe to be exact.

[Doc]

Yep only under decel/engine braking.

Huh? a leak from the header or at the pipe/ slip on connection?

[duey]

Originally posted by Doc
Yep only under decel/engine braking.

Huh? a leak from the header or at the pipe/ slip on connection?

I'm not 100% sure on what its called on the bike but on a car its considered a "bung" that usually the o2 sensor is located. I am told that that "plug" on our pipes is for dyno tuning which again is the same as a car since we use wideband o2 sensors to monitor air/fuel ratios to tune accordingly. Basically any type of exhaust leak will cause it to do that.

[KB]

New pipes may have more airflow/ less restrictive which is causing a lean condition on deceleration/closed throttle.

KB

[Doc]

Originally posted by rmbbikes
New pipes may have more airflow/ less restrictive which is causing a lean condition on deceleration/closed throttle.

KB

Ok so how do I fix it?

[KB]

Carb'd or FI?

I'm not the Ducati expert.

KB


Ok after just posting that and seeing it's a 92 I'm going to go with carb'd!

KB

[Doc]

Yep Carbed,

I guess I could turn the mixture screws out (in?) a lil...

I don't think I need to rejet...