The bike's measurements are WAY off. That's not true speed as it the bike is not calibrated correctly (most motorcycles share this same issue). Closer calibrations if the 19" front rim/tire is put on it. The bike can do ~80 max when measured with GPS. When I did the bike review, we conducted a series of highway tests to ensure we were getting a true sense of top speed of the machine. 77 mph was able to be obtained fairly quickly (in RX3 terms) and up to 80 took a while, in a tuck and did not stay there - waivered back between 77 & 80 depending on various environmental factors.

With the 19" front wheel and OEM tire my speedo reading was within 1 mph of GPS @ 70 or so. The 18" front tire gave me at least a 10% error. I would not trust the tach to be accurate enough to translate that into mph speed. The factory does test each machine on a dyno. As I recall, the machines that do not reach 84mph are sent back for re-work. Remember, that 84 mph is on the dyno...no air drag, no wind, no hills. I think it's safe to say that the stock bike with an average rider will top out around 75 mph. Of course YMMV.

Peter Y.

Well, here's a couple that have no complaints about their RX3 on the highway.
http://californiascooterco.com/blog/?p=28042

Dug up this old thread because it has a reasonable discussion of top speeds under different circumstances. Rode I26, I40, and TN22 from Saluda NC to Midway TN, the last 6 hours in constant rain. Rolling through the mountains at first light, 96mph indicated down hill. No problem maintaining 70mph (speed of traffic on the interstate) most of the time now that the engine is broken in. Need a GPS on the bike to get accurate speeds, but I'm too uncaring about such pickiness to blow the money.

i found a used speedo dv something can't remember what it's real name is there is a thread on it but now speedo is right on was easy to install and can program for different tire and sprocket combinations SpeedoDRD that's it

SpeedoDRD. I had one on my RX3 and it was easy to make the speedo perfect. Since it requires splicing into the speedo wires, you can buy the bare wire kit from them OR any of them with a plug for any bike and just cut off the plug...It may be a way to save a few bucks. Spud put a good tutorial on how to wire in on this forum.

I use Kentucky Windage on the speedo.

Oh, guess I should mention at over 80mph with a heavy load in the bags the front end gets light once a couple gallons of fuel is used. Bad wobble. Refill the tank, no wobble, no butt pucker. I think this might be what put me in a coma for 5 days when I landed on my head at 65mph. I have installed some significantly heavier headlights (pair 4x6 45w LEDs) and will see how that does next chance I get to ride.

Got the bike to 75 ish (per GPS) with the 13t front sprocket and it really didn't do much for me down low compared to the stocker. So lost about 5 mph with the change.

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.

Good input, Sully. Places like Texas have long ways between stops. Hence, speed is a real time saver. Try riding across Texas at 55mph. You are looking at 13 hours drive time on the quickest routes, not counting traffic slowdowns, fuel stops, or potty breaks. Frankly, if you can't make time better have lots of it.

Worst thing on long, lonely highways are road trains. Some smaller ones, doubles and triples, can pop up almost anywhere in North America. Some longer rigs are occasionally seen in Canada and western U. S. of A. in remote areas.

Australia is worse--road trains at 160kph on gravel. Talk about getting pounded! One learns quickly when motorcycle touring rural Australia to watch for road trains, and when you see the dust rising get 50 meters away from the road and marvel at so much mass going so fast. Not unusual to see trains with 6-12 trailers. Record seekers have hooked 120+ trailers to a single mover and driven them short distances. That's a rig just shy of a mile long rolling down the highway.

So, lots of miles brings out some solutions that seem silly to people who live in places crowded with traffic and everything within a few miles of home.

80mph is my limit on the highway, less if a significant headwind. Without a windshield the wind blast wracks my neck. With a windshield can't hardly keep a bike with upright ergos heading in the right direction. Wind and turbulence from passing vehicles compromises stability. Definitely a safety issue. Doesn't seem to mater if I'm on a RX3, CB550, Nighthawk 750, or most any other bike with upright ergos. That's why I ditched the windshield on my RX3, replacing it with a flat visor held on with the stock hardware through holes drilled in the right places.

My last ride was 8 hours at 70mph, with the last 6 hours in steady rain with temps between 40* and 50*F. The RX3 was capable and confident as long as I kept her below 80mph to avoid speed wobbles. The RX3 performed well until I go bad gas. No more Shell for my little Chinese honey.

Oh, got a 300 jug and piston for my RX3 on the way. Still going up a couple teeth on the rear wheel sprocket, too. Ought to pull well out of the hole.

I put the idea of an RX3 on hold, and snagged an SSR Buccaneer 250i. On this bike I've been greatly enjoying riding on the backroads, and it will do highway travel with varying degrees of success. In medium traffic on flat roads, it's perfect. I can use cars as a wind break and easily hang out in the fast lane at 75-80mph. But on lonely interstates with only slight uphill grades, I'm doing 65-70mph flat out. If I'm running up a bigger hill I have to downshift to 4th gear, which tops out at 70 indicated (66 actual).

I *could* tour on this bike, if it were equipped with bags and a rack, but this is slightly below where I consider comfortable. Short stints on the highway aren't a problem, but I'd not really want to tour on it. At least not on the highways. But it has helped me consider what I'd need a bike to be able to do.

To be adequate, I'd need to be able to easily hold 75mph (actual) on a highway with mild hills. I'm not talking steep grades, I'm talking hills you don't even realize are hills until you're on an under-powered 250. Central NC piedmont hills. Ideally I'd like it to do 80mph, but adequate is 75mph in these conditions.

To be exceptional, it needs to be able to hold 75 up steep grades on I40 around the eastern Asheville area. I don't expect this from the RX3. I'd call it adequate and be happy if it can do 65mph up those grades. There are a lot of cars that can't manage that.

Thoughts?

Charles.

Note that as my Buccaneer broke in, it holds speed better. Also, going to a smaller rear tire (equivalent of 2 more teeth on the rear sprocket) completely changed the bike. It holds speed far more easily now, and tops out at 88mph indicated.

Charles.

You Need A Bigger Bike
 

You need to be looking at a larger class of machine, if a steady 75-80 MPH is what you want from a bike without stressing the engine or the rider. Assuming that low cost is one of your primary criteria, then one of the new Royal Enfield 650cc twins, either the Continental GT or the INT, should be on your list, if it has to be a new bike . The RX4 should do it also, but a twin would be much better at it. Otherwise, look at a used Suzuki VStrom 650 or Kawasaki Versys 650. I have the Versys, and I can vouch for the fact that it will do 75-80 all day long, with luggage, and not break a sweat. You can find low mileage, 1-2 year old Vstroms and Versys' for around $5000-$6000. Many come with luggage. Here is a 2017 Versys 650LT, with 5600 miles on it, in your neck of the woods:

https://raleigh.craigslist.org/mcd/d...858681703.html

Other used bikes to consider would be the Yamaha FZ-07 or the more touring oriented FJ-09, now known as the MT-07 and Tracer 900, respectively.

I never felt comfortable on my RX3 at sustained 70+ mph runs. The bike just didn't feel right and it was thumping the engine.... No.... Daily sustained speeds you're talking about would surely be handled better on something a bit bigger.....just an old fat mans opinion.