# Bachmann Spectrum 2-8-0 Question

Discussion in 'N / Z Scale Model Trains' started by roryglasgow, Jun 24, 2003.

1. ### roryglasgowActive Member

Those of you who have them or have seen them run... About how fast do these models run at top speed? I've clocked mine at a scale top speed of 20 mph. Is that typical for this model?
2. ### ClerkActive Member

Rory, I just clocked my 2 - 8 - 0 at 75 mph at max speed for just a short distance. I usualle run it batween 45 and 55 mph. I don't know why your's will not go faster unless something is binding.
3. ### K.V.DivMember

My 3 travel at 74, 79 and 80 scale miles per hour respectively.
Methinks that you have either a binding problem or that you have a shay dressed up as a conie.
Cheers.

Terry
4. ### billkActive Member

Clerk and KV are probably right. Just wanted to add that the max voltage put out by your power supply would come into the equation, too. So we should really be talking MPH at a given voltage level.
5. ### roryglasgowActive Member

Well, I suppose that it could be my power supply... It says that it puts out up to 13 volts at 400 milliamps. That doesn't sound to beefy on the amperage side... I'll try another power pack and see if it does any better...
6. ### belgMember

For us newbies could someone tell us how you calculate scale miles per hour?
7. ### billkActive Member

Just time how a train takes to travel a measured distance. Here's an example:

Measure off a distance of 100 (actual) inches, and measure the time it takes the train to cover that distance - say it takes 50 sec.

That means at the same speed it would travel 100 * 60/50 inches in a minute, and 100 * 60*60/50 = 7200 inches in an hour.

Then convert the 7200 inches to your scale, for N scale that would be 7200 * 160 = 1,152,200 inches per hour, which is about 18.2 miles per hour (1,152,000 / 12 inches per foot / 5280 feet per mile).

Converting all this to a magic formula:
N-Scale MPH = Distance traveled in real inches /
(0.11 * Seconds taken to travel that distance)
8. ### ClerkActive Member

Here is a "N" Scale speed scale somebody worked up for me using a 36" yard stick

Seconds to travel 36"......... MPH
65................................................... 5
22 ...................................................15
13.....................................................25
9....................................................... 45
5........................................................60
4........................................................75
3.........................................................90

There may be somebody out there that will argue and break it down to milaseconds or some such thing but this is close enough for me.
9. ### roryglasgowActive Member

Yep, it was the power pack! She zips along like she's rocket powered, now...
10. ### ClerkActive Member

Glad you found the problem Rory. I think it would have taken me a long time to check out the power supply.
11. ### WaytechNew Member

Here is a webpage that I have a calculator on.

(I do not know who created the calculator, or I would give them the credit)

Speed Calculator

Wayne
12. ### ClerkActive Member

Wayne. Thanks for posting that URL for the speed calculator. That is much more accurate then the one I have.
13. ### MCL_RDGMember

And here all the...

...time I been using the "Looks a little too fast (conversely- little too slow) method" for whether my train crews (me) were observing the speed limits.