CO value yamaha XT 660 R
 

Hello Kev,
firts of all i would like to congratulate you for all your work and knowlodge on xt 660 R!!!

I have a xt660R from 2010. I live in Azores (portugal - in the middle of Atlantic ocean).

My CO value is 21. I still have surging. Do you think i should increase that value? Or decrease? what is your opinion?

I do not have any mod or change. It's fully original.

Cheers
Luis Pedro Cabral

The CO will not help, mate. You have to buy Kev's O2 mod and fuel mod to cure the surging. Leave the CO at original level i.e. 15

Make your own.:wow:

Not seen anyone make their own O2 controller on a XT660?

Theoretically plausable but doubt it :D
No one has done it so it is not so easy, save the headache and PM Kev with the order ;)

Its possible.:glasses7:

Thank you for all your answers.

So i will try with Co at 15...

Regards
LPC