[3-Wheeler]

Hi Metro,

For someone wanting to get some coast-down numbers, what have you determined to be a reasonable mph to start the test?

So far I've heard something like 100 kmh, which is close to 62 mph.

For data logging, I have a Garmin hand-held and can set it to record mph data every two seconds.

Also, we have to keep track of the actual baro and temperature for each run.

I'm planning on recording these numbers over the course of the winter and into spring time. That way I can build up a data base of numbers and see how consistent the coast down tests are.

I used Google Earth to find several stretches of road that are flat within a few feet over a 1/4 mile or so. The plan is to use the same stretch of road and start accumulating data. This is one of the roads I take to work.

Then when I make some runs with the under body panels off, I can get several runs and compare to the data base already accumulated. This will also give an idea on just how variable the coast down process is.

Performing this testing over the next few months will allow one to see the effects of the colder air and higher baro, and hopefully have an idea what the coast down numbers should be for various outside conditions.

With enough data, we can extrapolate to data values that we do not have, within reason.

Obviously I'd like to keep my top speed to a minimum to be legal, yet get some good numbers.

If anyone has ideas on this, please let me know.

Jim.