Speedometer

[Mr Jangles_imp]

1st post here, has anyone checked there speedometer against there GPS to see if they match? previous bikes I've owner always read higher than the actual speed.
Thanks

[Randy B]

From what I have seen posted this bike is just about spot on.

[flynrider]

I did this last year. This was my first bike with a non-mechanical speedo (which are notoriously inaccurate at higher speeds). Edit : I meant mechanical speedos are notoriously inaccurate.

I grabbed my plane GPS and strapped it to the bars. Up to 95 mph, they were within 2 mph of each other. By far the most accurate speedo I've ever had on a bike.

[Cormanus]

Have a look [url=Http://cb1100forum.com/forum/showthread.php?tid=3330&pid=49065#pid49065]here at the post on the Lake Superior 1K. Ole says:

Quote:Can't fig out why my CB1100 odometer says 1094 miles for the lap yet the Garmin Nuvi 550 says 1062? Anybody want to comment on this? Are Honda odometers that bad?
My experience is that at 110kph on the speedo, the actual speed according to my GPS is around 104kph.

[Mr Jangles_imp]

My Harley I traded for my CB was spot on too, my Vstrom 650 was way off.
Thanks, now I know.

[AzBob_imp]

Mine reads 1mph higher than the GPS.

[Bike #12_imp]

Mine also reads 1 mph higher than GPS, in the 70 mph range.

[pekingduck]

Can we assume GPS to be 100% accurate? If there were 5 different GPS devices in the same car, would they all read the same after 100 miles?
Here are a couple questions I'd have that may account for some inaccuracies why GPS might record lower mileage. Sorry in advance for the rambling.

GPS devices rely on transmitted signals that can be interupted by trees, clouds, tunnels etc.
You're in tight twisties with tree cover, GPS loses signal for a couple secs, recovers and jumped across the ravine while you ran a hundred feet farther and back. It also does not track elevation well.
You go over a slight rise, down a little drop, and the difference is that you went a little farther than the crow flies.
Rear tire slippage. It occurs all the time, even though we don't feel it. It's the main (only?) reason tires wear.
One last point, a small one, maybe crazy. GPS is mounted at a fixed point, lets say along the centerline of the bike. As you lean, the GPS is moved a foot or two to the inside of the turn, and thus is going around a smaller radius, meaning a little less distance traveled.
Your mileage WILL vary.

[the Ferret]

I think weight, heat and the abrasive surface of the road especially during braking are the main reasons tire wear, not slippage, although slippage would certainly accelerate wear.

[redbirds_imp]

My wife's V-strom shows 64mph when I show 60 on the CB. My Garmin CXS shows the speedometer on the CB to be quite accurate, nearly spot on. About 1mph optimistic.