My Rocket 3 GT Speedometer is out!

[technoguppy]

@technoguppy please tell us what the difference is in MPH between the speedo and the GPS is at a few different speeds. Slow, Medium, Fast and Warp Speed.

Next time it gets over 13C I'll try to do just that.

Snowed in Toronto yesterday, calling for more today. June is looking good though!

 

[idk]

With cruise control on my Jeep set at 65mph the GPS is in exact agreement.

The original RIII's speedometer is about 7% optimistic, IIRC, but the odometer was correct. If you adjusted the speedometer to be correct then the odometer would be pessimistic. I imagine that is also true with the new model as well.

 

[Wadejesu]

I have TuneECU with android working on my TFC, can clear service light, haven't tried speedo cal yet, I'll check it out and report back.

 

[Bernard Vinet]

To get the right speed I use the GPS reading. It's the most accurate in the world. They navigate really big boats around the world with these things.

 

[scot in exile]

To get the right speed I use the GPS reading. It's the most accurate in the world. They navigate really big boats around the world with these things.

A wee bird tells me that the big boats have a bit more sophisticated GPS on the boats i also use my GPS on my work van or the few times I have it on my bike

 

[Dr.D]

Probably has saved me numerous speeding tickets. I like to think I’m going really fast.

 

[Lamonster]

Mine is about 4mph faster than the gps.

 

[barbagris]

They navigate really big boats around the world with these things.

Thing is though that boats generally have pretty much unobstructed vision, inside their own little hemispheric view of the sky. GPS han be REALLY flakey in valleys - Cities with tall buildings (so called urban canyons) and narrow streets - and the real killer - tunnels. Even quite high end GPS speedos lose signal fast. TomTom etc have really cruddy averaging algorithms to make you think it's all OK.

A good SPEED sensor needs more satellite coverage than a locator. Especially if you expect it to calculate speed up and downhill. More sources and reliable strength.

I run industrial (Hummingbird Electronics from OZ) GPS speed sensors on the R3 and KTM. The R3 has an external antena - KTM does not - But the receiver is under a flimsy plastic cover. But they can both take a while (cold start) to find coverage in less than perfect conditions. And they will "blink" even under a wide bridge.

U-Blox in Switzerland do have a dead reckoning chip where the speedo pulses are corroborated via GPS - but mfr's seem reluctant to fit them. Odd as their chips are inside quite a few devices. My guess is it's a legislative restriction.

 

[idk]

It may also be worth noting that although they can see miles ahead and around them, and that there is generally not police radar waiting to catch them, and they often have the opportunity to speed, very few ships reach the same speeds as some of our more adventurous riders may attain, which could change the parameters needed for GPS speed monitoring.

 

[Larry_M]

Probably has saved me numerous speeding tickets. I like to think I’m going really fast.

Good point!
I don't really care if my speedo's a little off, as long as it shows more than i'm really going. I have selective OCD, like side mounted plates.. *cringe*