Ducati Monster Forum

Hello!

I've had issues ever since replacing the stock exhaust on my 2020 Monster 821. I had Termi's installed, with the T800 (100% verified the proper map was applied successfully,) and it gave me loads of backfiring and rough idle. I've unplugged the O2(lambda) sensors as per Termigoni customer support, but still having the same issues. I went back to the stock map, and still having the same issues. The stock map with the stock exhaust does not give me any issues.

I've attached a video of the idle, and the backfiring only really occurs in 1st gear when throttle is completely closed (IE: coming to a stopsign, slowing to make a turn, etc) The only thing I've found that will cause changes in this, is when I have the clutch fully pulled in, it seems to make the idling slightly worse and close to shutting off. When I let the clutch out to an area before it would enter the friction zone, it seems to not have idle dips at all.

Please help :D



https://vimeo.com/743811976

It seems the common denominator is the exhaust. The Termis need more than the T800 map if they are straight through with no DB killers or sporty inserts.
Additional tuning will probably be required by other means with other reflash maps or mapping of additional devices.

Sometimes the TPS needs resetting with some flash loads.

Late style Termis can be obnoxiously loud without some type of DB killer. The can pop and backfired with their large diameter openings on the over run. Kamna in Germany have racing DB killers which can settle them right down without costing any noticeable power. They are designed for circuit racing at tracks with noise restrictions. They are still plenty loud.

It's hard to say if further tuning by other means will completely solve the issue although I would think that correcting any imbalance in the tune caused by large diameter pipes would help. I don't know why Termi went to the giant exhaust outlets on later pipes.

I understand this is a bit of apple to oranges, but...

I put slip-ons on my 796... no remap, no intake mods... and it FIXED all the backfiring through the intake, the hiccup and die at lights, and the lugging issues.  I would opine that it is running a little lean... it pops on throttle roll-off some... but it starts and idles like a purring kitty.

It almost sounds like you have the wrong map, or there is a significant intake restriction... something like that.

Did you perform any other work on the engine's electrical?

Have you check for any intake and/or exhaust leaks?

Correct fuel presure?

Correct TPS setting? Back when 821s came out, 2013[IIRC] and you 'flashed' them idle would be of the 'surging type', usually fixed by resetting TPS with the DDS2.0

To get to the VE/Spark tables you need very sophisticated software, a tuner would need to do a few adjustments to take care of the 'popping' and the idle issue[btw. video did not play in my pc] so assuming your idle is surging or hunting hi-low while keeping the Termi on the bike ... If not, have a fabricator, fabricate a 'baffle' to slow down the flow of gases, this should create enough back presure to take care of idle and maybe popping   ??? ??? ???

Just brainstorming hier a few ideas, wish you find solution in a timely manner since you mention that it also happens with ori map and Termi

Wait...a Duc with a clutch cable??????????????????

Yup ... started with the 821 ...

Nothing changed on this besides the T800 and the slip-on. I'm not sure how to reliably check for intake or exhaust leaks, but would love some advice. I had a local shop who reset the TPS. Something worth mentioning is that if the bike isn't up to 170 or hotter in temp, going from 2nd to 1st and stopping will cause the bike to shut off. I have a Competition Werkes exhaust that I put on as well, but still the same issues. If it is a mapping issue, (and I know for 1000000% sure it was the proper map applied for the Termi's) then it will be hard to fix here in California. Most shops/dealers won't touch fueling due to severe emissions regulations.

I agree that the denominator is the exhaust. I've tried a Comp Werkes that had the same issue (which would follow the logic behind the large diameter openings on overrun.) Even with the DB killer inserted in both the termi's and the CW, it still happens. I also have a K&N air filter, but it happened with the stock air filter as well. I heard something about using blockoff plates for the PAIR system, so that extra air is prevented from being introduced into the equation. Reportedly this helps. However, I feel this shouldn't be necessary. Am I wrong?

Well, after this, only advice left from me to you: Back to the dealer and THEY need to sort it out ... It is NOT normal and only the DDS2.0 can do this job ...

BTW, forgot to ask, does your 821 have 1 or 2 O2 sensors[before and after cat]?

Yeah, except my dealers here in California are almost 100% guaranteed to not touch my bike since they are so heavily regulated for emissions and such. They can't sell nor do fueling adjustments according to them.

 I have 2 O2 sensors. I've tried unplugging both, and leaving both plugged in.

You'll have to find a shop outside of CA ... From what you say, map seems to be way too lean at idle and possible under 15% TPS ... A Rexxer map could be a solution but, you would have to contact them and explain the situation ... In the meantime, I would sacrifice the looks and sound for peace of mind and return to OEM as long as you don't a solution ... I mean, DNA should be able to offer a solution if this is an accessory from the Ducati catalog or ... ???