OK, let me start by admitting I have no idea how fuel injection works apart from reading something online 10 minutes ago, where I discovered that open loop and closed loop have nothing to do with froot loops.

I just went for a 40 mile ride, and paid close attention to this "surging" I'd heard about. The only thing I could notice was an on/off feeling once every second or two holding 25mph in 2nd gear. Anywhere else, I couldn't notice any issue at all.

Halfway through the ride I pulled over and started pushing buttons until I got to the Co1 setting, which was at 15. Having no idea what this setting really affects, I set it to 20 and headed for home.

I hoped it would get rid of the 2nd gear, 25mph issue (which isn't really an issue as I had to look for it), but it didn't. However, for a start the bike seemed a little louder. More growly. GRRRRR!

Also, 3rd gear normal acceleration seemed a bit swifter. And certainly more growly. GRRRR!!

Confused by what I thought I was seeing, I pulled over and reset the Co1 to 15. I *think* it seemed to go back to it's slightly milder self.

So I'm confused. I don't think the Co1 setting does much under normal riding, but it seemed to me it was like adding a sports exhaust, new air filter and power commander all in one.

Is this totally a case of the emperor's new clothes. Did I imagine it all?

I have just finished playing around with mine as well, but other mods also. Maybe try and leave the setting up for longer, then go back and see the difference. I too was having surge issues around the 50km mark, but the bike will now sit comfortably in 4th and chug along. I have removed the dB killers from my pipes, so don't need any attention from the men in blue from a spluttering bike. But it really does make a difference.

Doh!!

Welcome to

Still not sure the CO setting does anything one the 2009 model. I upped it to 25 today (up 10) and I'm not convinced it's any different. The crap fuelling at 25mph is no different. I still think it might be better at acceleration but I really don't know. I think this bike is fine from the showroom and all tinkering is in the head!

Some are ok from day one, so it's not a rarity that you might have a faultless result. The O2 sensor makes it harder for the CO2 settings to work, that's for sure.

You need to control the close & open loop fuelling with an O2 controller + a fuel mod to get the best ride.

The CO1 only adjusts the A/F ratio at idle & just off idle.

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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