Running lean

[red lion]

2002 LeMans. All stock, Ran grate, Then I installed a new set of Mistral exhaust, Now the bike is missing around 2800 RPM. What do I need to do to get it running good again?  Can deferent exhaust change the CO? do I need a new map?

[audiomick]

Same bike as mine, and the same problem. It "coughs" occasionally at a constant 2,800 revs, like when I'm going through a town after a stretch of open road. The difference is, I believe mine has a standard exhaust.

 

I was going to start my own topic about that, but I think I will now wait and see what comes up here.

 

PS: I don't have the impression that mine is running too lean. It feels more like some kind of "interruption".

[docc]

There are numerous contributors to the cough. Often, performing a "Decent tune-up" addresses it adequately. Simplest solution is not to lug our V11 along sub-4000 rpm. There are other significant reasons not to, as well.

It may not actually be "lean" as much as the map at that point has significantly more ignition advance than necessary. @Lucky Phil showed us this clearly.

 

[red lion]

My bike ran perfect before the exhaust change. How could that be timing or tune up  related. Also it missed more after the bike warmed up. I think it's running lean, so how do I adjust the fuel mixture?

[audiomick]

32 minutes ago, docc said:

Often, performing a "Decent tune-up" addresses it adequately

Thanks for the info about the map, docc. The "decent tune-up" is on the list, and will be carried out as soon as possible.

8 minutes ago, red lion said:

My bike ran perfect before the exhaust change.

Without wanting to cast any doubt on your ability to observe your bike's behaviour, maybe the problem was there with the old exhaust, but so minimal that you didn't notice it. Perhaps the new exhaust has just brought a latent problem to light?

Also, maybe there is no connection to the new exhaust. For instance, one of my thoughts was that the TPS pots on mine, or at least one of them, have a glitch at the corresponding throttle opening. What I'm getting at is, the causality between "I changed something" and "I have a problem that I didn't have before" is highly likely. Nevertheless, one should not forget the possibility of a pure coincidence.

As I wrote, mine exhibits apparently the same behaviour, and mine has, as far as I know, a standard exhaust. There may be no correlation at all between my problem and yours, but my experience might also be a clue that your new exhaust is not the cause of the problem.

[p6x]

If it can be of any help, my V11 Le Mans 2004 exhibits the same "coughing" are around 3000 rpm, sometimes below that too.

Yesterday I did about a 130 miles run, in an acceptable temperature. The "coughing" happens less than when the temperature is in the 90's and more.

I have StayInTune exhausts without the DB killers. That is how I got the bike. In any case, since I started to ride it, the engine missing at about 3000 rpm, sometimes less always was there.

While I don't like it, I have not yet been able to do anything about it. However it is on my "Todo" list for this end of year.

[docc]

2 hours ago, red lion said:

My bike ran perfect before the exhaust change. How could that be timing or tune up  related. Also it missed more after the bike warmed up. I think it's running lean, so how do I adjust the fuel mixture?

@red lion, did you only change the canisters? Not the collector/crossover as well?

[red lion]

I only changed the canisters. it has stock crossover but I did remove the baffles from the canisters. Most manufactures say to remap/adjust fuel mixture if the baffles are removed.

[docc]

Have you checked where your CO Fuel Trim is set now?

[Kevin_T]

Please don't just blindly think that you need more fuel to solve all your problems. I'm a victim of such a previous owner. Running too rich a mixture is destructive to your engine as well. Those nikasil cylinders are sensitive to having the oil washed off the walls. Setting trim a little here or there is fine but if you want to go far it's going to require data logging.

I mean the previous owner of my bike was just Bat Sh*t Crazy. I should have never bought the bike. After riding it a while I could smell the fuel in the oil. Many many Problems.

[red lion]

No I don't know how to set the fuel trim. 

[audiomick]

Have you read through the "decent tune up" topic that docc linked further up? It's in there.

https://www.v11lemans.com/forums/topic/19610-decent-tune-up/

 

I would strongly reccomend going through and doing all the stuff in the that thread before you start in on the engine management. Playing around with that doesn't make much sense until you know that all the basics are where they are supposed to be.

[Kevin_T]

I don't mean to mess with your head it's just the phrase, "I think it's running lean". My problems are not yours I only shared it to keep you from doing something drastic.  A good flow chart would look like: Grooming your exhaust making sure there isn't any leaks and the engagement on the joints are good. Follow yours doctors advise and do what he prescribed with a good tune up. Check your electrical connections and relays reducing voltage drops and spikes. Do another good tune up. Clean throttle bodies, and injectors. Do another good tune up. Then start with fuel trim and possibly maps.

The fact that something has changed with the Mistral modification is good. If it didn't change the fuel mixture in some way would mean they're nothing more than 900 dollars worth of cosmetic jewelry.  

[red lion]

Is this the correct cable to set CO trim?  From Lonelec.  Guzzidiag JP diag. Ducati diag kit- interface+adaptor (kit + 3 pin set)? SKU#LEZBGUZKIT01

[docc]

That's it! 

https://www.lonelec.com/product/guzzidiag-3pin-interface-cable-kit/

Consider, also, the breakout harness to set your TPS.

Do you have a way to balance your throttle bodies?