Right I've been trying to decide whether to post this or not as I know the surging and bad fuelling of the other XT's was documented. In the last 100miles (bike is at 1450) I've started to experience a slight surge with the bike on a steady throttle. It initially occurred at the dreaded 3000rpm and is obvious there as that's 30mph in 3rd gear, so I'm there quite often. Then I started to notice it at 4000rpm and also 5000rpm.
It's nowhere near as bad as the Caponord was before I used Tuneboy to remap the ECU, but it is noticeable, and it is annoying. Has anyone else had it?
I'm loath to take my bike back to the dealers unless I really have to as last time it went in in came back leaking oil and with spongy front brakes.

I've felt what I can best describe as a slight hesitation on a constant throttle once or twice in the last week or so. I put this down to FI adjusting itself to air temp or some other variable momentarily.

Only felt it in top gear cruising at 65 to 70mph, it hesitates a couple of times(that running out of fuel feeling) and then everything is smooth again.

I am not sure if this is of much help. Firstly, no, I haven't experienced the kind of surging you are talking about. However, when I start the bike and let the bike warm up a couple minutes, especially after a cold night (and I leave the bike outside as I don't have a garage), I could hear small clicking sounds along with the sounds as if the throttle is adjusting itself gently. I think this is where the fuel injections are at work. In addition, I have got into the habit of reving it up to over 4000rpm a couple times during the warmup. I read it somewhere it's good for the bike especially on cold start. At the end of the warmup, the clicking sound subsides and the engine sound stabilizes. If I don't let the bike warm up properly, the idling speed is on the high side closer to 2000rpm rather than 1500rpm as indicated in the manual. After a while, the idling speed would go back to normal. Still, I have not experienced the surging you are talking about. My point is that if you haven't done so, perhaps warming up the bike first would help? Just a wild guess.

I still think that the best way to warm up a bike is to ride it. At idle speed, the oil pump is turning slowly and the pressure is low. While driving the oil heat up gently and is ciculating a lot faster in your engine. Reving it up without loading it, not my peace of cake. But, hey that me .

The surging issue, i think all modern (environmental friendly) FI bikes used to do this, some more than others. I can live with it.

Sounds a lot like what I had when I'd had the bike for a similar mileage. I was concerned that my Tenere might have FI issues (this is my first bike mind).

Anyway, turns out it was just my chain getting too loose! The manual specs have the chain a lot looser than on other bikes (confirmed by my mechanic) and after having it serviced by my dealer the setting they used was just loose enough to give this effect after my 6000 service. I tightened it myself afterwards by a small amount (once accessable twist on the adjusting nut with a spanner) and it was enough to get rid of this effect. Needless to say overtightening a chain is worse than having it too loose so don't try that either
The chain should just be able to touch the swingarm if you push it up (without having to press too firmly) based on my dealers adjustments and my modification to clear the jerkiness.

It is particuarly noticable on a low constant throttle (30 mph in 3rd particuarly) which seems to be what you've had, and results in the bike jerking around a lot and a delay in takeup of speen when you open the throttle.

Of course if I am teaching you to suck eggs then feel to throw them back at me

No egg sucking happening here I admit I was looking at the Mikuni TM38 in the shed and wondering if I could convert the Ten to carb mind!
I've already checked the brakes to see if they were dragging and they were fine. The chain was looking a little slack last night but I'll check again in daylight and report back. Cheers for the ideas.

I experience a slight surging at 5000rpm, but don't find it annoying... i just settle for a bit higher (or lower) cruising speed.

I do suspect it might be related to ambient temperature, and will monitor this behaviour when temperatures go up...

Still think it's one of the best running big singles...

HJ

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Riding the Mad Mule !! ... no more... went orange...

I would never rev my cold motor to 4000 rpm during warm up. The most wear in a motor takes place during warm up faze until every component has expanded to it's running clearance. By reving the motor when cold you rapidly heat up the piston & with the cylinder still cold you can cause piston to cylinder damage, I have seen this first hand many times.

If you run the motor to long at stand still during warm up you get fuel dilution in the oil, due to a very rich fuel mixture during the warm up faze.

I would recommend one to only warm up a motor for max 30 second then ride the bike with low rev's & nothing above 3000 rpm for the first mile or two until the motor is at running temp.

The cold start idle up valve is adjustable, so if the bike idles at 2000 rpm during cold starting, adjust the valve so it idles at 1750 rpm when cold. The bike should not idle at 1500 from a cold start it should be around the 1750 mark, how long it idles at that rpm depends on the what temp the idle valve thermostst is at.

Where to adjust the cold idle up valve. This done on the left side of the throttle body, remove the black blanking plug to get to the nut.

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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

Today, outside temperature 6-8 degrees, on my commuting trip I took some special notice on the 5000rpm surge.... there was none... smooth as ....whatever. So my impression is that it seems to be related to outside temperature.

Again: it's not a problem ... it's behaviour.... call it character.... buy a inline 4 if you want smoothness (or an electric scooter!).

HJ

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Riding the Mad Mule !! ... no more... went orange...

Thanks Kev. I will try out your method then.