speedo off.

[Porko]

Anyone check speedo accuracy with gps? My 700X with Metzler z8 tires is off 8 km. showing too fast. Actual speed is 5 mph slower than shown on speedo. Can Honda speed's be calibrated?

 

[SuperMek]

It's about the same readouts I get on my X. It is quite common that speedos in any vehicle show some 5-10% more than actual speed.

 

[BigMike]

True.....gives you the impression that you're speeding, when you're not. Just go 8 clicks over the posted speed limit and you good to go!

 

[happy]

I was going so fast, I had no time to check the dash....

 

[SuperMek]

I was going so fast, I had no time to check the dash....

You
did
not!

 

[670cc]

Assuming the speedometer determines speed by countershaft rotational speed, I suppose (IF there is room) you could raise the countershaft sprocket 1 tooth to 17. It would raise the gearing 6.25% and the bike would be going that much faster for a given engine RPM, thus improving the speedo accuracy. On the down side it might make 6th gear less usable by being too tall.

Greg

 

[Beemerphile]

Assuming the speedometer determines speed by countershaft rotational speed, I suppose (IF there is room) you could raise the countershaft sprocket 1 tooth to 17. It would raise the gearing 6.25% and the bike would be going that much faster for a given engine RPM, thus improving the speedo accuracy. On the down side it might make 6th gear less usable by being too tall.

Greg

It does not detect on the countershaft. I can't tell exactly from the picture where it is taking it, but it appears to be from a gear within the transmission. It is bolted into a hole in the top right of the transmission.

 

[happy]

As I do not often speed (wink wink), I do not really need to know the real speed, etc.
By the time I see the flash, it is usually too late.

Go as fast as your deep pockets go...

Last month a friend here just lost his license for 12 months. He was going 138km in a 80km zone. Cost him some thousands chf also.
Ouch.

 

[mpgandfun]

I've passed a few of those radar signs on the road. The ones that say "Your speed" then show your speed as you pass them. My speedo has been right on, or 1 mph higher. I don't know if these signs are calibrated to the accuracy that police radar is, but I'd imagine they've gotta be pretty close.

 

[670cc]

It does not detect on the countershaft. I can't tell exactly from the picture where it is taking it, but it appears to be from a gear within the transmission. It is bolted into a hole in the top right of the transmission.

By countershaft, I meant the transmission output shaft itself or anything attached and rotating with it at the same RPM. Either way, since there is no sensor on either wheel on the manual bike, the instrument must assume rear tire size and sprocket sizes to calculate a displayed speed. So changing tire size or sprockets will alter the speedo accuracy, in some cases making it more accurate, I presume.

Greg

 

[Cyclerosis]

Huh! Sounds like every bike I've ever had! They've all indicated a faster than actual speed, according to gps.

 

[gpd211]

Not sure if speedo healer makes anything for the nc yet. The problem with changing the sprocket size or adding a speedo healer is it will throw the odometer off. I bet if you check the odometer is pretty accurate. On my VFR the odometer is spot on but the speedo is optimistic.

 

[Beemerphile]

By countershaft, I meant the transmission output shaft

Sorry Greg, I ran right past what you said. I think it is reading a gear on the countershaft.

 

[arefog]

My experience matches mpgandfun. I went past one of those radar speed signs at an indicated 37mph and the sign angrily flashed 37 at me (it was a 35 mph zone). I've also noticed that if I try the usual 5-8% over that most bikes require I pass more cars than usual. Your results may vary........

Dick Fogg

 

[670cc]

I just got my Garmin Nuvi 500/550 mounted on the NC700X. I went out this evening and checked the speedometer accuracy. This is a US spec model.

The results were much to my liking. It's very good to know that the indicator is accurate. Apparently the rest of the world is not getting the same calibration as the US models? Readings in Miles per Hour with stock Metzeler tire:

GPS NCX
30 30
45 45-46
70 71

 

[Beemerphile]

My manual trans non-ABS bike reads right on with the GPS. I wonder if this is a DCT only issue. Does anyone have a DCT bike that reads right on? The primary gearing and final gearing is quite different between the two, however the overall gearing (primary x final x overdrive ratio) is very close to the same. The vehicle speed sensor reads before the final gearing so there would need to be a way to compensate in the display controller.

 

[N97972]

My manual trans non-ABS bike reads right on with the GPS. I wonder if this is a DCT only issue. Does anyone have a DCT bike that reads right on? The primary gearing and final gearing is quite different between the two, however the overall gearing (primary x final x overdrive ratio) is very close to the same. The vehicle speed sensor reads before the final gearing so there would need to be a way to compensate in the display controller.

This was my thought as well, as my last 3 Honda's have been on by multiple gps checks. all have been non ABS units.... a '09 NT700, '11 CBR250R, and the '12 NC700X

 

[tweak89]

Using my mounted Garmin E-trex as a control, my speedo ranged from dead on to +/- 1 mph depending on the wind conditions. One of the most accurate speedos I have ever encountered on a bike.

 

[turbodieseli4i6]

Using my mounted Garmin E-trex as a control, my speedo ranged from dead on to +/- 1 mph depending on the wind conditions. One of the most accurate speedos I have ever encountered on a bike.

Same here! I'm very impressed with the accuracy on this bike.