09/ 2012
Update new O2 Controller mod plug & Play

http://www.xt660.com/showthread.php?t=14746&page=17




18/12/2010

I now have a mod that will reduce the surging for the 2007 to present XT660X/R's with O2 sensor, it's a new O2 controller that turns off the O2 sensor completely (Closed Loop circuit) this allows us to remap the fuelling using a Power Commander across the whole fuel map without the intervention of the closed loop circuit.

All the details are here. Kev's 2010 New O2 Mod for XTX & XTR's
http://www.xt660.com/showthread.php?t=14746

They can be bought from EBay or via PM to me.


Been doing some testing with the 5VK-8591A-11 ECU today which is fitted to the XTX & XTR 2009 models onwards.

This is what the surge looks like on a Air/Fuel ratio logger with the standard yamaha fuel map, no fuelling device fitted. I have a Dynojet Wideband O2 data logger that shows & logs the A/F ratio in real time. As you can see roughly ever 10 seconds at 10% throttle & 2500RPM, the bike switchs between rich & lean which is what the rider feels when it surges, this recording was taken while riding. It should be around the 13:1 mark for best HP/Torque & be constant not up & down all the time. I will remap the ECU using my PCIII in this range & post the results soon.

http://www.youtube.com/watch?v=ZwTfuwZZ848

The ideal A/F Ratio for our bikes is around 13:2.

I am working with different set ups to try & find the best solutionfor this ECU.

http://www.youtube.com/watch?v=K5ubpdHu3uY

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Mods that I have done to my XTX's

My 04 XTX
Stage 1 & 2 DNA filters / Kev fuel mod / snorkel mod / Drilled air box mod / Engine breather mod / Fork Spacer mod / 15w fork oil /
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My 07 XTX
Raptor 700 cylinder 102mm / Modified Crank Case to take a 105mm Raptor Cylinder / 11:1 102mm JE Raptor piston / Stage 1 Raptor Hot Cam / Ported head / Colder Spark Plug / +2mm Throttle body / DNA stage 1 & 2 filters / Modified Air Box / Snorkel removed / Worry Brothers stage 2 filter cover / 6mm & 8mm Bolts Replaced with Titanium Bolts / Recovered seat in Black / O2 Eliminator /

My 09 XTX
59HP at the rear wheel / Stage 2 Raptor Hot Cam / DNA stage 3 Air Box / Carbon Can Exhausts / Modified Exhaust Link Pipes / PCIII With Custom Fuel Map / Wideband Commander O2 Data logger / LCD100 Dyno Jet display & fuel adjuster / 2500 OHM HT lead instead of a 10K OHM XT lead / Extra Coolant Cooler / Protaper Fat Bars / Tail Tidy With LED Tail Light / OKE Protection Knobs / LED indicators / AIS blocked / Modified rear sprocket rubbers / Rear Foot Pegs removed / 09 ECU With 02 Sensor Changed To A 06 ECU / Complete wiring harnes Changed from 09 to 04 / Home made LED resistor flasher / Hole drilled in the fuel tank filler neck to allow quicker filling / Modified Bar End Weights / Progressive front fork springs, 15W fork oil, forks lowered 25mm, used XTR rear links lowering the rear 20mm, rear spring one click stiffer / Changed front & rear guards from blue to black / 47T rear sprocket / Speedo Healer V4.0 / Kev throttle cam mod / Throttle grip mod / The new 2010 O2 sensor mod is out, works a treat, The new 2012 O2 Controller is out, PM me for details

Now ride a 2018 MT09SP ABS + TCS

My KTM 990 SMR Mod book. http://www.ktmsmt.com/viewtopic.php?f=13&t=4946