[Sullybiker]

Highway performance is a tricky area on all bikes that aren't designed for it. Remember, in a lot of countries outside the US it's not uncommon to see 125-250cc bikes everywhere as they're in a cost bracket most can afford; just like the US bigger bikes get considerably more expensive. In Southern Spain, you might be surprised to see midsize scooters on the freeway, usually pushing 65ish. One difference is drivers are used to this, and do not expect them to keep pace. In the US drivers can become very dysfunctional if they have to interrupt their phone usage to pass a slower vehicle. Also in many places abroad tractor trailers are restricted to 56mph/90kph so they're much less intimidating on the open road. Differential traffic speeds seem much more commonplace elsewhere. At least in my experience.


The starting point is what you consider highway capable. Average speed of traffic, average low speed, or average high speed? In theory any bike capable of the average low should be absolutely fine. Some consider this dangerous; that's a matter of judgement and experience.



What's also interesting is that I ride with several friends that have supernakeds and they hate them on the highway: Just because you have enough power to cruise at 85mph effortlessly does not necessarily mean it's at all pleasant to do so. 70 is the sweetspot before wind starts creating a fatigue problem after more than a half hour.

My Ninja 300 can cruise at 85 and has good wind protection, but I can't ride it for more than 90 minutes at a time as my legs and back start to let me know in no uncertain terms that they're not having fun. Bear in mind that there are still people that don't consider the Ninja 300 highway capable, because it can't hold a 100mph cruise. This is considered the minimum performance level for parts of Texas. I think that's insane, but I don't live there.

I have not ridden an RX3, but if you can find a torque/power curve it's almost identical to the Ninja 300 up to 9000rpm, so it performs dead-on where most 250 street bikes are, like the TU-250X (which I know pretty well). Not terribly quick, but good enough. In other words, they'll get you there.

The 300cc phenomenon has been driven by the track in Kawasaki's case, but it's also been very positive for the US market as it's allowed full interstate performance for small motorcycles. There's still going to be compromise, though. Looking at the X-300, I still don't think I would choose it over an RX3, unless it was a strict commuter, but that's my choice.