I've just finished fitting all mine today (pics soon)

The O2 mod makes the biggest difference, pulling from 2K RPM in 4th, no problem.

KevMod and DNA stage 2 just tidies it all up a bit.
Off the clutch for roundabouts, cruise at 30 in 4th for town riding.

I'd really recommend the whole lot, but start with ththe the O2 mod.

You still won't change much in 5th gear, but any lower gears are altered vastly.

Why aren't Yamaha doing this?!

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Bike: 2013 XT660Z, TKC70 tyres

Mods:
Barkbusters, Scottoiler, DIY Tail Mod, DNA Stage 3, Power Commander V & O2 Eliminator, Exan X-Black Stainless exhaust, Tool tube, Ohlins linear front fork springs, Nitron rear shock, JT front and Supersprox rear sprockets, D.I.D. VX 520 chain, Adventure Spec bashplate, DIY USB Outlet, DIY chain guide, Kev's Throttle mod

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