I'm a bit of a heretic here - but be aware I ride an 1173cc roadbike as well.
Taking a GTS - 250 or 300 - on a freeway at freeway speed is operating at the edge of its envelope. It certainly can be done, but it has a few quirks which may affect you. I'd hazard a guess that most of the regular freeway riders here are already used to these things and take them in their stride - so can you, but I think it helps to know upfront.
1. 12" wheels, short-ish wheelbase, quick steering and limited suspension travel all affect how the GTS 'feels' at highway speed. I call it "skittish" .. the scoots isn't going to go down, but sometimes it can feel that way until you get used to it. I'd say my GTS (with aftermarket suspension) is stable to 60mph on smooth roads. After that, it gets to feel "light" so that by 70mph I'm conscious of riding through this "skittish" feeling. As I got used to it, it became more of a "quirk" than an "irk" - but even after three years, I'm still conscious of it.
2. The motor / CVT / gearing is really set for town and (I think) it's out of puff very quickly after 60mph. I've ridden highways and the open road with 244cc and 278cc machines and all lose speed on long or steep hills, and in stiff headwinds. This is eminemntly manageable, but you will experience it. Big trucks come up behind awfully fast if your speed falls to 50mph!
3. It takes more effort than an open-road machine. As fun as a GTS is, it's a city scoot and on the open road it has to be "ridden" where a larger machine takes less effort. This "riding" is a lot ( a LOT ) of fun, but it does tire you out. (KUDOSKUDOSKUDOS at this point to the iron butt riders .. dunno HOW you did it!!!!)
4. Fast on bumpy roads takes a LOT of nerve!!! I've been airborne a few times ... fun, fun, fun - but it does happen!
That's my experience. Hope it helps.
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