From: "Steve Tyng" Subject: RE: Speed eqation Date: 6 Aug 2004 12:10:00 -0400 Reply-To: tanks-at-rctankcombat.com

```I don't know about your motor rpm but if you know the drive wheel rpm and diameter
you can figure MPH with the following formula,

MPH = ((RPM x (DIA x 3.1416)) x 60) / 63360

In Excel it would look like,

=((A1*(A2*3.1416))*60)/63360  where A1 is RPM and A2 is drive wheel diameter.

Remember diameter times Pi (3.1416) gets you your circumference.  The 63360 is the
number of inches in a mile.

For a tracked vehicle you should add the thickness (times 2) of your track to the
DIA variable in the equation for an accurate result.  If the drive wheel is 4.5
inches in diameter and the track thickness is 1/2", add an inch to DIA (5.5" for
this example).

Steve Tyng

> Subject: Speed eqation
>
>
>
> Ok so here i am looking at my motors tring to figure out how
> fast or slow my tank will go  ?        If i know the drive
> wheel size is 4 1/8 " and the speed of my motor  ( x ) rpm .
> What is the formula to figure out MPH? Do i need more info to
> determine mph ? Thanks.
>
> Nick "gotta work on my typing " Barnes
>
>

```

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