Ask Ollie, he's got both WR's. He bought my 250R. I'm 5'8" and had a Seat Concept seat which makes it an inch higher, plus I had a lowering link, 'twas fine for me. Steve Harcoss had the shock shorted for him I believe??
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Culmstock area - Devon TRF Group member - KTM 690 Enduro
The R is a road biased trail bike and the F is an Enduro biased bike fully ok for trail riding. So as mentioned lots of differences with suspension, weight, power delivery, fuel consumption, service intervals, hardiness.
Depends on your riding style and what you want the bike for. The R looks nice but my choice would be the feistier wr250f (I've had one of these). But obviously feisty is my thing as I've now got a ktm200exc 2 stroke which is as feisty as they get.
Buy the F model if you're just doing trails or enduros. Buy the R if you need to cover more road mileage or take luggage - perfect for strapping bags on and riding down through France or Spain taking in all the trails
Bloody heavy compared to the F though, although the servicing costs and hours will be much less. 6 speed gearbox so more relaxed at sustained cruising speeds (they're geared for near on 90mph as standard) F model much more fun on the trails though - you really notice the lack of weight in comparison.
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Caution - the poster may well have been drinking........
F all the way, but I'm biased after having one I saw an R fall over not long back on to soft ground, the footpeg crumpled That said, I also saw the same R go over in water with no water intake unlike my F