Question for Pig9r or Warp9.9

Guys,

I have a question for you... I understand that eliminating the 02 sensor prevents the bike from going in to closed loop and therefore does not allow the ECU to "adapt" or make changes to the fuel map.

Interestingly enough, Although I have the 02 sensor eliminated, I still seem to be seeing the fuel map change depending on how I ride the bike. If I do a long "drone" on the highway, it leans out. If I ride hard and am grabbing handfulls of throttle under a load, it richens itself. I can hear the difference in the fuel map based upon the exhaust note. When runnning rich it is loud and throaty, when lean it sounds like a sewing machine. I do not get any popping on deceleration in either condition (rich or lean)

My R3T has the 02 sensor eliminator installed and I plugged the pipe with an M18 bolt. I have also deselected the 02 sensor using Tune Edit. I have an underseat K&N and am running TORS. I have downloaded, and am running, tune # 20258 with secondaries set at 100%


The bike itself runs great, the changing in the exhaust note is a bit annoying.

Perhaps my understanding of what happens when the 02 sensor being eliminated is either incorrect or incomplete?

Would love to hear your thoughts on the matter.

GPmaz, I meant to include you as well or any other "techie" on this list. Appreciate any and all thoughts on the matter.

CB

if you look at your fuel maps you will see that it leans out at mid throttle/ mid rpm ranges for better fuel economy cruzin. the maps are richer at the higher throttle positions for more power. this is done so you can have the best of both worlds, good power for play & fuel economy for cruzin.

have you put it on a dyno and checked the a/f ratios to make sure its not too lean?

For an everyday rider, you wouldn't want the a/f ratio to be the same across the board. If you pull up the a/f maps you will see at smaller throttle openings that the a/f ratio is leaner and it gets richer with the larger openings.

Either way I would get a dyno tune to get the most out of your upgrades and for peace of mind. I would suspect that you are lean all the way around after adding a K&N and TORs and still running a Triumph tune. In fact I would not eliminate the O2 unless you are running a custom dyno tune or have had one done. If you are running too lean (which is sounds like you are), because of the mods you have made, the engine can't correct it.

Maybe why it sounds different after running it hard is because it gets hot and running lean is making it even hotter?

I am by no means an expert on the effect of eliminating the O2 sensor.

That said, from what I've been able to get from those that know more than I is that the O2 sensor will lean the bike out in closed loop. With a Scangauge attached I've seen the bike go into closed loop in normal cruise situations. Any increase in throttle will throw it into open loop, and thus take the A/F settings from the loaded map.

What I don't think is true (and I could certainly be wrong here) is that the O2 sensor being present will actually effect the map itself and somehow change it according to how you ride.

I believe the bottom line is that with the O2 sensor installed the bike will run quite lean at cruise, not a bad thing, and revert to the map in all other situations. With it removed the bike will run off the map at all times (always remaining in open loop). Again, from what I've heard, with the O2 sensor installed the transition from closed to open loop does give you the chance of a brief period where you are running too lean as the ECU transitions from the lean condition of closed loop to the richer condition dictated by the installed map.

As I said, that's just my understanding. I could be wrong.

The bike will run at stoich (14.57 to 1) when in closed loop. Not a bad thing, not good for performance and decel popping or afterfiring will return at closed throttle when the engine is overrunning. Otherwise when open loop it is relying on what the fuel tables are telling it. So if more air is moving through the engine because of intake or exhaust mods, the ECU has no way of knowing when open loop.

While the stock tunes are closed loop for a small portion of the a/f map, on your average (right elbow horizontal to the ground) ride, you will spend a large portion of the time in that range (closed loop).

Pig9r said:

The bike will run at stoich (14.57 to 1) when in closed loop. Not a bad thing, not good for performance and decel popping or afterfiring will return at closed throttle when the engine is overrunning. Otherwise when open loop it is relying on what the fuel tables are telling it. So if more air is moving through the engine because of intake or exhaust mods, the ECU has no way of knowing when open loop.

While the stock tunes are closed loop for a small portion of the a/f map, on your average (right elbow horizontal to the ground) ride, you will spend a large portion of the time in that range (closed loop).

Click to expand...

Hey Pig9r did you get the PCV installed and runing yet. Inquiring minds want to know or at least a dumb Polock is curious

The change in exhaust note is not caused by the heat of the engine. It is clearly caused by a change in the fuel map. I have seen this before with my old 955cc Triumph race bike when it was in street condition. I put the TOR pipe on the Daytona and then downloaded Triumph's tune for that pipe. I did not eliminate the 02 sensor at the time. The bike did the exact same thing. It would lean out on hiway drones and sound like a sewing machine until I grabbed a few handful's under a load, then it would revert to a throaty exhaust note. Once converted to a roadracer, it was no longer an annoyance. It was always being ridden hard.

The tune I am using is a tune from Wayne's site for R3T's with an aftermarket exhaust. Sorry, I should have mentioned it before. I am not sure if this tune was modified by Wayne or if it is a stock tune from Triumph.

GPMAZ, what about your tune posted in "trading Tunes" / "Modified Tunes for R3T" section. I am referring to the one that produces 117hp and 138 ftlbs of torque. It is labeled "20235TuneModSEC100.

Is that tune compatable with my current bike configuration? Please see my initial post to understand current bike config.

CB

Bob from Tune Boy how to

[FONT=Arial,Bold][FONT=Arial,Bold]

Closed Loop Mode​

[/FONT][/FONT]

Many bikes now come with O2 sensors to allow the ECU to adjust the fuel mixture to provide
smooth running under light throttle conditions.
The ECU can only go into closed loop mode when the target air/fuel ratio is 14.5 – 14.7 to 1.
Looking at the above air/fuel target table and the tune constants, you can see that the only
time this tune will run in closed loop is at idle and very small throttle openings.
For the bikes with the Keihin ECU you can disable the closed loop mode by removing the​

tick from the “O2 sensor fitted” box

so if you do not want the changes in the exhaust tone you could alter the A/F ratios at cruise speed to something below 14.5:1 and leave the idle area alone and it will be like forcing it to run open loop at higher road speeds and yet have the closed loop at idle and any other area you decide not to change. If I were going to do this I would start with small changes say like 13.88 that way you might still save some fuel economy in them areas and yet gain the power and exhaust note you want.

Just and Idea I got after reading things a couple times whilst on the technical library

Captain Bob said:

The tune I am using is a tune from Wayne's site for R3T's with an aftermarket exhaust. Sorry, I should have mentioned it before. I am not sure if this tune was modified by Wayne or if it is a stock tune from Triumph.

GPMAZ, what about your tune posted in "trading Tunes" / "Modified Tunes for R3T" section. I am referring to the one that produces 117hp and 138 ftlbs of torque. It is labeled "20235TuneModSEC100.

Is that tune compatable with my current bike configuration? Please see my initial post to understand current bike config.

CB

Click to expand...

Yes, that tune should work fine. There is a good chance that the tune you're running is the same one though. Wayne and I worked together quite a bit as I had the first R3T he had tried to tune. As I recall that tune was the result of his initial stab at a tune, followed by my trip to the dyno, his subsequent changes based on the initial results, and a follow up trip to the dyno to check A/F ratios.