Guinness
|
| posted on 21/9/05 at 08:33 PM |
|
|
Speedo Calibration
At my SVA my digital speedo was low throughout the range, usually only by 0.1 - 0.5mph, but anything too low is a fail.
My speedo has a single magnet mounted on the front offside wheel and you enter your wheel / tyre circumference in 10ths of inches. I put in
713inch/10. This was fractionally too low. If I want it to read higher I have to make it think it is travelling further for every revolution of the
magnet? So increasing the wheel / tyre size should put the apparent speed up? Is that right or am I barking?
Help
Mike
|
|
|
|
|
andylancaster3000
|
| posted on 21/9/05 at 09:01 PM |
|
|
Could you not reset the speedo? Then adjust the diameter to a tenth or so higher?
Andy
|
|
|
Hellfire
|
| posted on 21/9/05 at 09:57 PM |
|
|
I had a similar dilemma and worked it out like this.
If your speedo is correct you travel 60 miles per one hour.
You are indicating that you are travelling 59 when in reality you are travelling 60.
Therefore you need to increase pulses on your speedo for that distance hence you reduce your circumference/diameter by 2-3%. This will give you a
slightly over-reading.
That's how I did it - seemed to work 
|
|
|
Peteff
|
| posted on 21/9/05 at 11:10 PM |
|
|
So increasing the wheel / tyre size should put the apparent speed up
That's how my pushbike speedo works. It multiplies the times the magnet passes the sensor by the tyre circumference so if you put in a bigger
circumference you get a higher speed reading.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
Hellfire
|
| posted on 21/9/05 at 11:41 PM |
|
|
quote:
Originally posted by Peteff
That's how my pushbike speedo works. It multiplies the times the magnet passes the sensor by the tyre circumference so if you put in a bigger
circumference you get a higher speed reading.
If that's how it works then I stand corrected...
|
|
|
A.J
|
| posted on 9/10/05 at 10:18 PM |
|
|
I had a similar problem with my mechanical speedo when I went for my SVA. My solution was to take the needle of the dial and reset so it didn’t quite
read zero.
For the purpose of the SVA test your speedo can read slightly fast, providing it falls within the tolerances. You will need to look these up in the
SVA manual.
|
|
|
tks
|
| posted on 10/10/05 at 08:21 PM |
|
|
jejeje
Speed = distance / time
the more distance in the same time results an bigger speed!
sow if you increase the wheel diameter or the circumstance (wheel diameter * pi)
then automaticly your speed reading is going upwards....
Tks
The above comments are always meant to be from the above persons perspective.
|
|
|
