Kymco AK 550 speedo offset

[rjs987]

Only one of my past bikes had an accurate speedometer. All the others were optimistically offset by up to 10%. IOW- My Burgman 650, for example, would show 55 mph when I was actually going 50 mph. This was based on comparing what the speedometer was showing with what my GPS was showing. GPS speed is commonly only 0.3% offset so plenty close enough for comparison to actual.

Last year I timed how long it took between mile markers on my AK 550 and found that it was close to 5% offset to actual. But wanting to test more accurately I used Google Maps navigation on my phone today while riding an assortment of roads with different speed limits from 35 mph up to including out on the Interstate highway. The speed limit on our Interstate highway around here is 70 mph, though most traffic is significantly over that. I found that the speedometer offset on MY AK is about 5.5% optimistic which is close to what I was seeing by timing my speed between mile markers. I like knowing what my speedometer is actually showing me regardless if I intend to go the speed limit (or perhaps a little more) so that is why I do such testing.

While I am somewhat math oriented and can calculate things like this on the fly I also like to keep some things simple.
So I'll simply add a few mph to the indicated speed and know how close I am to actual. I could post a chart but that would be too much. 

[Stig / Major Tom]

Yep. Saw the same with the speedo on my Honda Forza, Suzuki Burgman 400, Piaggio  Liberty150i and my Kymco LIKE200I.....all ran @10% optimistic ---- which is easy to deal with in town and the open road.
Stig
Once, when I had to go with a slightly oversized tire-- my Forza became spot-on!

[rjs987]

5.5% optimistic is just a little more difficult to manage than the easy 10% offset. But once you figure out how to simply split the difference about halfway between actual and 10% over it becomes much easier again.

[Mancashire]

5.5% optimistic is just a little more difficult to manage than the easy 10% offset. But once you figure out how to simply split the difference about halfway between actual and 10% over it becomes much easier again.

Did you happen to test accuracy of odometer?

[rjs987]

Did you happen to test accuracy of odometer?

Not yet. Not really concerned about that as much. It is less important that the odometer is so accurate as long as it is close. Any issues where odometer miles comes into play will go with whatever it shows regardless how accurate or not accurate it may be. On my past bikes the odo has usually been about 3% optomistic. So it would not surprise me if the odo on my AK is closer to 2% optomistic. As indicated by the above posts already submitted the offset of the speedo does vary from on AK 550 to another AK 550. This is also normal in my experience. Tire psi and wear and also the exact brand and model of tire as well as the wear on the drive belts, both final drive and CVT will factor into the accuracy of odometer and indicated speed at least a little.