IMO, every Adventure bike has compromises.... you're asking one bike to perform multiple, very different tasks and each bike will excel in one area, while leaving something to be desired in another. The best thing you can do is ride each bike you're interested in. Seat time will really help you decide what fits your needs, I can't stress this enough. I have bought bikes based on the internet hype and been quite disappointed with how it worked for me. IMO having a bigger bike means more power at freeway speeds and less getting blown around on the freeway. If you want to travel and cover some miles, a bigger bike (larger than a 650) is best.
I've owned several adventure bikes, I'll try give a run down of them from my experience.
The Suzuki DR650 is a killer, low budget adventure bike with a huge following with great aftermarket support, so you can built it how you want. The subframe is super stout, unlike the Honda 650's. Air cooled, simple engine. Suspension is cheap, but it works. Bigger aftermarket tank is needed, options as big as an 8 gallon tank! Easy to ride, lower seat height but no fairing means you're always in the wind at highway speeds.
The V-Strom is very much a road touring bike that is capable on limited dirt adventures. It's the kind of bike that is super smooth and comfortable eating up road miles. If you want to cover some ground on the street, the V-Strom is a great option. Low seat height, nice fairings, comfortable seating position. A rough 2 track is asking a lot of a V-Strom, the suspension, ground clearance, wheels, etc aren't built for harder trails.
The KTM 690 is a super fun dual sport, with a small gas tank. It get's good MPG, but if you're looking for real mileage range, bigger tanks are needed.... but not cheap. Great factory suspension, super sporty on road and off. Gobs of HP for a single cyl bike. Capable of bombing down the freeway, but lack of any real fairing makes it tiring.
KTM 990 Adventure.... IMO the perfect adventure bike. Way more power than needed, pretty decent suspension out of the box, good sized gas tanks, incredibly capable in the dirt. Probably one of the most dirt capable ADV bikes offered. Enough fairing to be comfortable on the freeway for hours. I thought the 990 was more capable than I was, but still loved riding it.
I think the KTM 1190 and 1090 Adventure are similar to the 990, but newer, more refined and even more capable.
I haven't cared for the Honda Africa and it's weird clutch, IMO Honda builds middle of the road stuff. Tame, predictable and blaaaa... boring.
I feel similar about BMW's, the big GSA is so big you better know how to ride it offroad if you plan on anything rougher than a dirt road. The GS800 wasn't my cup of tea either.
Hope that helps and feel free to ask if you need more info!
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