I've done a search and read the threads about gearing. My bike came with a 16 front sprocket but the dealer I got it off also gave me a 15 sprocket. Is it worth it and will I notice that much difference if I change it. Is it going to be a night and day difference or is it marginal.

It all depends on where you ride, a 15 tooth is better for twisty roads, a 16 tooth is better for freeway cruising.

With a 16 tooth sprocket the speedo will be reading incorrectly.

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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

Did you buy it new ???

I did a fair bit of work on the Tenere gearing last year, have a look at

http://www.xt660.com/showthread.php?t=8876

There's a lot of guff about fitting a speedo healer but the content is fairly explanatory.

The standard is a 15 and comes with a speedo error of about 8-10%.
A 16 will bring it more into line but it will throw the odometer out. The odometer is fairly accurate with a 15t.

On top of that you may find that it goes faster in 4th than 5th especially loaded or with a head wind or slight incline. (with the 16t)

As Kev said, it also makes a lot of difference as to how you want to use the bike. I currently have a 14t on the front and it make off road and traffic driving a lot better, but I fitted the speedo healer to bring it back to the original error of 8-9%.

OGR

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