I have some trouble with the closed loop fuelling being very touchy because it runs too lean (damned emission regulations 
) It's like riding with some chain lash on very small throttle openings and even in B mode on the Tracer it's not smooth when you open the throttle from fully closed. This is hindering smooth gear changes and things like fine control when putting the power back on for a corner exit. It's also annoying riding like this in town traffic. I read that there is a C0 setting per cylinder that can be used to richen things up a bit. On the XT660 forum I found some instructions, but they didn't quite match what I saw on the Tracer when I went to go do them so I took pictures. I hope this helps someone else, but please research the C0 setting first before you make any changes so that you know what you're changing and what the effects are. This is only a guide, it's your responsibility to know what you're changing and to live with the results (may they be good results!)
Start by making sure your kill switch is in the STOP position.
Press and hold both the TCS and RESET buttons and then turn the ignition ON. Doing this is a bit tricky, you need some force to press them in well, but you can feel them engage when you do.
Keep holding the buttons and after about 8-10 seconds and the right side of the display will flash ECU, let go of both buttons when this shows.
Now press and hold the TCS and RESET buttons again for about 3-4 seconds and you should see DIAG at the top of the screen, let go when this shows.
Press the TCS button once and the screen should show C0 now.
Now press and hold both TCS and RESET buttons again until C0 and 01 shows in the middle of the screen (takes 3-4 seconds), let go when this shows.
Pressing TCS or RESET now will cycle through 01 --> 02 --> 03 --> 01 --> etc. This changes the cylinder data that you're going to look at/modify.
When you are on the cylinder number that you want to modify, press and hold the TCS and RESET buttons for 3-4 seconds and an extra DATA field will appear, let go when this shows.
I have a stock bike, my values were showing 0 for all three cylinders. Pressing TCS or RESET will modify this value up or down. I didn't check, but I think the range is from -128 to 128. I set all three my cylinders to 10 and will see how it feels on the way to work tomorrow.
Once you've set a specific cylinder you can step back by pressing the TCS and RESET buttons together once and letting go right away. You'll be back to the previous level where you can pick between the cylinder 01, 02 or 03. If you're done setting all the cylinders there is no way to step further back than where you choose which cylinder to view/modify so simply turn the ignition off, all values are saved on the fly as you modify them. I recommend going back in and checking that all the C0 values are as you set them (assuming you made changes) before you start the bike with the new settings. As far as I'm aware, all cylinders should always be set to the same number.
) It's like riding with some chain lash on very small throttle openings and even in B mode on the Tracer it's not smooth when you open the throttle from fully closed. This is hindering smooth gear changes and things like fine control when putting the power back on for a corner exit. It's also annoying riding like this in town traffic. I read that there is a C0 setting per cylinder that can be used to richen things up a bit. On the XT660 forum I found some instructions, but they didn't quite match what I saw on the Tracer when I went to go do them so I took pictures. I hope this helps someone else, but please research the C0 setting first before you make any changes so that you know what you're changing and what the effects are. This is only a guide, it's your responsibility to know what you're changing and to live with the results (may they be good results!)Start by making sure your kill switch is in the STOP position.
Press and hold both the TCS and RESET buttons and then turn the ignition ON. Doing this is a bit tricky, you need some force to press them in well, but you can feel them engage when you do.
Keep holding the buttons and after about 8-10 seconds and the right side of the display will flash ECU, let go of both buttons when this shows.
Now press and hold the TCS and RESET buttons again for about 3-4 seconds and you should see DIAG at the top of the screen, let go when this shows.
Press the TCS button once and the screen should show C0 now.
Now press and hold both TCS and RESET buttons again until C0 and 01 shows in the middle of the screen (takes 3-4 seconds), let go when this shows.
Pressing TCS or RESET now will cycle through 01 --> 02 --> 03 --> 01 --> etc. This changes the cylinder data that you're going to look at/modify.
When you are on the cylinder number that you want to modify, press and hold the TCS and RESET buttons for 3-4 seconds and an extra DATA field will appear, let go when this shows.
I have a stock bike, my values were showing 0 for all three cylinders. Pressing TCS or RESET will modify this value up or down. I didn't check, but I think the range is from -128 to 128. I set all three my cylinders to 10 and will see how it feels on the way to work tomorrow.
Once you've set a specific cylinder you can step back by pressing the TCS and RESET buttons together once and letting go right away. You'll be back to the previous level where you can pick between the cylinder 01, 02 or 03. If you're done setting all the cylinders there is no way to step further back than where you choose which cylinder to view/modify so simply turn the ignition off, all values are saved on the fly as you modify them. I recommend going back in and checking that all the C0 values are as you set them (assuming you made changes) before you start the bike with the new settings. As far as I'm aware, all cylinders should always be set to the same number.
