Dave,

You're exactly right. My 1k resistor is wired in series with the air temp sensor. When monitoring via the dash display it gives me zero to -8 degrees adjustment against CURRENT AMBIENT temp. This means that when set to say -5 it fools the bike and makes the mixture richer and will always do so at whatever the ambient temp is. I believe that the statement that the current Kev mod is 10k is incorrect. It is 1k.

My hunch (and it only a hunch) is that even with this active - when at low throttle openings the oxygen sensor reads the exhaust gas and cancels out the air temp adjustment that we have made and thus causes hesitation due to weak mixture.

I'm away in the US for a couple of weeks now and when I come back my plug and play oxygen sensor eliminator will have arrived from Kev and I'm hopeful that this will work. If not then a Power Commander will be the only way.

The new plug and play oxygen sensor eliminator is more sophisticated than the current one and is also easier to fit as it plugs directly into the harness in series with the O2 sensor. It adjusts the O2 sensor signal to richen up the mixture rather than trying to cancel it out altogether.

This is Kevs reply to my questionregarding the cheap,plug in O2eliminators you can buy on ebay. It's very much consistent with my hunch about the O2 sensor. Do you understand the closed loop and open loop ? I assume when closed loop the circuit is completed by the O2 sensor and gets feed back from it and when open it doesn't ?

The resistor type O2 eliminators do not work on the XT660X,R or Zs we have
proven this on the Dyno, the only 2 that do work is Dynojet's O2 Optimizer &
my O2 eliminator. I now have a new plug & play version O2 eliminator for the
X & R models, photos attached.

My fuel mod, a PCV or PCIII can only adjust the A/F ratio in the open loop,
as soon as you start cruising the closed loop comes into play & takes
readings from the O2 sensor & will lean the A/F ratio out again no matter
what fuelling device is fitted to your bike. To completely control the A/F
ratio you will require an O2 Optimizer or one of my O2 Eliminators[/COLOR]

__________________

White 2009 XTX. MTC Cans, K&N filter stage 1, DNA Stage 2, Kev mod, Co value +25 from std, New Kev O2 Controller, Dunlop Sportmax Mutant.
Montesa 4RT -best bike I've ever had by far !

3 teenage sons, 9 radio control models, Beta Evo 125, 6 push bikes - garage too small ! Not enough time to ride th' XT !

The older I get the better I used to be !!!