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speedometer and the trip.

1970Custom

They call me Spuds
14,107
447
Middleton, ID
If my speedometer is of by 15-20 MPH, how far will the trip be off and how can I figure out the correct distance I've been traveling?


Also, how many teeth should I go on the speedometer gear to get the correct speed showing?
 

LEB Ben

Arrogant A-hole At-Large
34,919
1,124
outside your house
First off it depends on how fast you were going when you were off at those speeds. As for teeth, you can divide current tire size by original tire size...take that number and multiply it by your current tooth count. Oh and you can get trip length by multip[lying speed by amount of time traveld. IE...if you were reading 60mph, and you're actually traveling 75mph...and you traveled for 4 hours...that means you traveled 300 miles.
 
Last edited:

1970Custom

They call me Spuds
14,107
447
Middleton, ID
Doesn't matter, it's off by that much all the time, this is an estimate of course because I don't know how fast I was going but I do know, generally, how long it takes to get from place to place and how many seconds it takes to go a mile at say 55mph...
 

LEB Ben

Arrogant A-hole At-Large
34,919
1,124
outside your house
So when you're traveling 30mph, it says you're going 15mph? And when you're traveling 75 it says you're traveling 60mph? Typically, if it's that gear, it'll be proportionate and not a constant inaccuracy.
 

taxreliever

Licensed to Represent!
14,695
287
Maine
Use a gps, garmin or tom tom. Otherwise go through Ben's calculations.
 

taxreliever

Licensed to Represent!
14,695
287
Maine
Just add 20% to your miles it shows that you have driven
 

73F100Shortbed

That's how we roll!
5,937
320
NJ
First off it depends on how fast you were going when you were off at those speeds. As for teeth, you can divide current tire size by original tire size...take that number and multiply it by your current tooth count. Oh and you can get trip length by multip[lying speed by amount of time traveld. IE...if you were reading 60mph, and you're actually traveling 75mph...and you traveled for 4 hours...that means you traveled 300 miles.

Sounds like one of those math problems. If one train is travelling at 60mph and the other train is travelling at 75mph. How long does it take...

 

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