Modern Buddy

SCOOTER SPEEDOMETER HELP

I bought a new scooter about a year ago. Ever since, I have not been able to determine how accurate the built in speedometer really is and I hope someone out there can shed some light.

It comes as no surprise the dashboard defaults to KM. As such, these are the larger numbers for speed, as well as the so called mileage reading. The smaller numbers in green indicate miles and/or MPH.

I learned early on to divide the KM by 1.609 and/or multiply by .6 and convert to mileage and/or MPH. I am however, not real good with math and this has been difficult for me, even with a good calculator. Doing the different equations also give different results.

I have since added an app on my smart phone called cyclemeter.com. This does the conversion automatically and is based on GPS tracking. On longer rides, this program works well but drains the I-Phone battery.

I have also added very recently the Garmin Edge 200 which I like very much. This device is very easy to use and only needs charging about once every 12 hours. It also is based on GPS tracking.

Both devices on GPS are giving identical readings and converting from KM to MPH within a .10 of a mile. So it is these I would naturally think are most reliable.

However, here’s where it gets a bit confusing:

The dashboard printing for speed indicates that at 32KM is equal to 20MPH. This can be confirmed by looking up and converting these numbers on line.

The issue is when riding, the Garmin Edge and/or the Cyclemeter app indicates that to achieve 20MPH in real time, the dashboard indicator is up near 40KM.

This also asks the question, how accurate is the odometer reading? Have I really gone nearly 7,000 KM and/or 4,200 miles?

I feel the GPS devices are certainly more reliable than the dashboard graphics. But can anyone explain why it is so different other than I selected a cheaper brand Chinese scooter?

Thanks in advance for any thoughts.

Chip on Cape Cod, Massachusetts

Well first off almost all PTW speedos are off with few exceptions, second...it's a Daix.

The speedometers on scooters (and other motorcycles) are almost never accurate, usually indicating that you're going faster than you really are. Because they do. It seems to be combination of the variable dimensions of tires, psychology, and legal liability.

In practice, it really isn't worth worrying about it too much, since it's rarely important to know with any precision how fast you're going: the right speed for conditions is most important. Just use your GPS to figure out what the speedo says when you're really going a few key speeds, and memorize those readings. So if it says "55kph"* you might know you're going about 30mph (good for residential roads), and if it says "100kph" you know you're going about 55mph.

*Your Mileage May Vary.

Sigmasports usa motorcycle speedomter model MC-10

$40.00 new including postage within the USA

Fabrication of handle bar accessory to hold the computer might be required. For me, I took a shelf bracket from the hardware store and bolted it through the mirror connection. Then attached a small pipe to the bracket to hold the computer.

Also, 2 type epoxy was used to place the magnet on the front rim

Programming the computer took awhile to figure out but I did get the hang of it and after that it was about 10 minutes.

Measure the tire height multiply by 25.4 multiply by 3.14 and determine wheel size programming code. ( 15.5 inch X 25.4 X 3.14 = code)

This computer can be programmed to the bike's original odometer reading and continue from that point.

KM divided by 1.609 = current odometer reading in MPH.

Note this is a WIRED unit for reliability and the cable was positively long enough to do the job.

For those of you who hate the KM dashboard this will allow you to have a MPH reading at all times.

Success @ last!