Author [ES] [CA] [PL] [PT] [IT] [DE] [FR] [NL] [DK] [NO] [GR] [TR] Topic: Speedo Sensor  (Read 2378 times)

0 Members and 1 Guest are viewing this topic.

Offline Harry H

  • XR Member
  • **
  • Posts: 74
  • Country: gb
  • Town: Sunny Surrey
Speedo Sensor
« on: April 03, 2017, 02:17:52 PM »
Was looking at the Nav on the bike yesterday and noticed that the Speedo compared to GPS is way over reading. I understand they all over read a little but were talking 10% at least.

OK I can allow for this but it annoys me a little about resale values and milage.

Where is the sensor?  If it's on the rear wheel or gear box then it could be down to the fact I'm running a 190/50 tyre at the moment as opposed to the 190/55  but if it's on the front wheel then I really don't think it should be that far out in this day and age.

Offline JRE

  • XR Pro
  • ***
  • Posts: 104
  • Country: us
  • Have a day
  • Bike: '16 S1000XR
  • Town: Cincinnati OH
Re: Speedo Sensor
« Reply #1 on: April 03, 2017, 02:29:13 PM »
I was just commenting on this the other day. Mine is high 7%. The Super Tenere I had was almost dead on accurate vs GPS which was the first bike I'd ever owned where that was the case. In this day and age, I don't know why they can't be more accurate...7-10% variance from the factory should be unacceptable. :232:
I know there are various speedo "healers" out there but I haven't personally looked into them for this bike (yet).
Joe

Offline Bob S

  • XR Pro
  • ***
  • Posts: 178
  • Country: gb
  • Town: Welwyn, Herts
Re: Speedo Sensor
« Reply #2 on: April 03, 2017, 02:31:23 PM »
My speedo is a lot closer to the sat nav speed, with a variation of 2-3 mph at speeds up to 70-80mph.

Offline ampj8

  • XR Pro
  • ***
  • Posts: 160
  • Country: ch
  • Bike: XR
Re: Speedo Sensor
« Reply #3 on: April 03, 2017, 03:07:22 PM »
First question is: Is the speedo reading influenced by the mileage of the tire?
Second would be: is the speedo adjustable to account tire usage?

It has to have something because otherwise how could the TC or ABS be accurate? if not?

Offline PL2112

  • XR Member
  • **
  • Posts: 85
  • Country: gb
  • Bike: S1000XR SE
  • Town: Canterbury
Re: Speedo Sensor
« Reply #4 on: April 03, 2017, 03:31:01 PM »
It's illegal for a speedo to under read, therefore most vehicle manufacturers make them at least 5% optimistic and often more.    Our car is exactly the same.

As for the OP's questions
First question:  Is the speedo reading influenced by the mileage of the tire?
Absolutely, the tire diameter reduces as it wears and hence has to rotate more often (i.e. faster) to travel the same distance.
Second would be: is the speedo adjustable to account tire usage?
No
And you'd be pretty miffed if you started getting speeding tickets when according to your speedo you were travelling at or below the speed limit because you hadn't set it up properly after a tyre change.

Offline Harry H

  • XR Member
  • **
  • Posts: 74
  • Country: gb
  • Town: Sunny Surrey
Re: Speedo Sensor
« Reply #5 on: April 03, 2017, 03:39:27 PM »
*Originally Posted by PL2112 [+]
As for the OP's questions
First question: 

The question was. Where's the speedo sensor. Back wheel, front wheel or gearbox ?

Offline ampj8

  • XR Pro
  • ***
  • Posts: 160
  • Country: ch
  • Bike: XR
Re: Speedo Sensor
« Reply #6 on: April 03, 2017, 03:46:59 PM »
Must be front wheel it must be that thing on the left where the ABS sensor is. It is called Front wheel speed sensor as per BMW manual.

Offline PL2112

  • XR Member
  • **
  • Posts: 85
  • Country: gb
  • Bike: S1000XR SE
  • Town: Canterbury
Re: Speedo Sensor
« Reply #7 on: April 03, 2017, 03:50:44 PM »
Sorry Harry H
I picked up AMPJ8's questions not yours doh! :138:

I'm not sure then where the sensor is, but it's more likely to be the front or rear wheel than the gearbox because it will use one of the phonic wheels that the ABS / traction control use.
You could try putting your bike on the centre stand and with the ignition on (but engine off) give the back wheel a spin.

Offline ampj8

  • XR Pro
  • ***
  • Posts: 160
  • Country: ch
  • Bike: XR
Re: Speedo Sensor
« Reply #8 on: April 03, 2017, 03:53:41 PM »
*Originally Posted by PL2112 [+]
Sorry Harry H
I picked up AMPJ8's questions not yours doh! :138:

I'm not sure then where the sensor is, but it's more likely to be the front or rear wheel than the gearbox because it will use one of the phonic wheels that the ABS / traction control use.
You could try putting your bike on the centre stand and with the ignition on (but engine off) give the back wheel a spin.

Or do a wheelie and while the front is up then pull front brake if it marks zero then you know  :008:

Offline meurig

  • XR Member
  • **
  • Posts: 41
  • Country: za
  • Bike: BMW S1000XR
  • Town: Cape Town
Re: Speedo Sensor
« Reply #9 on: April 03, 2017, 06:41:18 PM »
is there any higher profile front tyres?