Kidding the speedo...

[SpikeOne]

Does anyone know how the speedo reads the sensor ring on the front wheel on a modern scooter.
My experience is about a thousand years old when all we had was a cable driven by a small sprocket on the front wheel that span inside the speedo itself.
As I see it, the serrated ring spinning on the front wheels of modern scooters act through the sensor in a similar manner.
But are the actual pitch of the slots and the gaps in between significant. Does the computer in the bike "count" the slots and determine the road speed from that, or are the slots just to make it easier for the sensor the "see" the movement?
The reason why I ask is that the Downtown has an unreadable MPH scale and I was thinking of making a new ring with different spacings and slots to kid the speedo into reading in MPH instead, (assuming that this will even work!).
Anyone ever tried something like this?

[old geezer]

http://www.advrider.com/forums/showthread.php?t=675524&highlight=speedometer&page=2

[SpikeOne]

The speedo on the Downtown is electronically fed from a sensor on the front wheel and not driven by a cable I think...but interesting nevertheless.

[JustWantToRide]

Get a SpeedoHealer for about $100.  The only problem is that it will then change your odometer which was set more precisely (yep - the manufacturers purposely make the speedo's read optimisticly high).

[SpikeOne]

Speedohealer is not available in the Uk for Kymcos.
Shame that, that would have been cheaper...

[JustWantToRide]

SpikeOne:  Plug and Play would be nice - but I've always had to use the generic model and connect the wires myself - no big deal...   I emailed the people at SpeedoHealer and they quickly responded...  I verified - and you can order them from the UK distributor here:  http://www.bikersdiscountstore.co.uk/speedo-healer/healtech-electronics/speedo-healer-v4-pd-18.php

Cheers!

========================================================================

Hello Robert,

Thank you for your email.

The SpeedoHealer with the Universal harness kit should work fine.
Part number:
  SH-V4 + SH-U01

Kind Regards,
/Norbert
www.healtech-electronics.com


From: Robert 
Sent: Wednesday, August 17, 2011 17:15
To: support@healtech-electronics.com
Subject: SpeedoHealer


Do you make a generic SpeedoHealer which I could splice into the wiring on a
Kymco Xciting 500Ri or a Kymco Downtown 300i?  Thanks.

               Robert                                 

[SpikeOne]

That's brilliant. Thanks Rob.
I never thought of contacting them direct. I looked on their website myself and couldn't find  one, so I just assumed that it wasn't available.
How did you work out the wiring? Do they supply simple enough instructions to do it yourself?
How does the calibration work? Is it a case of running the bike with a satnav and adjusting it a bit at a time until it's right?

[JustWantToRide]

It's only 3 wires so it's pretty simple.  If I remember correctly it's power, ground, and speed sensor from the front wheel. 

If you know how much it is off - then you can set it and be pretty close right off.  To get them spot on you will want to take a GPS and get on the motorway at the speed limit for a minute or two (to ensure the GPS picks up your top speed).  The SpeedoHealer has a button you can press which will display your max speed - so you can compare it to your max speed from your GPS and adjust it again if you want. 

If you don't have a GPS, then have someone drive a vehicle at a preset speed (the higher the better).  Don't go faster than them so your max speed will be the speed you choose.  If you are going to do a max of 50mph, then have them go 45 until you get next to them and give them the thumbs up.  That way you won't go over 50 catching up to them. 

Kymco made engines for Honda for 20 years.  If you have a shop nearby you might remove your speed sensor box and take it in to the shop.  There are only 4 different Honda connectors - so you may be able to match it up and order a harness that you just plug in.  I'm going to try that with mine. 

Here's their instructions for programming the SpeedoHealers.
http://www.healtech-electronics.com/docs/SHv4_UsersGuide_en.pdf


A better option?  It looks like the Xciting 250Ri dash is the same as my 500Ri - except for reading 10mph lower.  The Downtown 300i seems to have the same situation with the Downtown 200i.  Since the speedometers are off by about 10% - we could change the dash plates to correct them.  That way we wouldn't throw our odometers off. 

[SpikeOne]

Thanks Rob.
That all looks pretty simple.
Once the warrenty has run out i shall think about investing in one.
Cheers