gear ratio/rpm/crawl ratio calculator

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Big Ray

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o.k. fellas...I'm sure some of you are familiar with this, I'm also sure some are not.
This is a really fine site for figuring your r.p.m.'s and speed, at specific tire sizes and gear ratios.
Or find a gear ratio for a specific r.p.m. with a specific tire size.
Or whatever else you may need to find...it is helpful if you're considering a gear change or if you're new to the hobby.

 

Tank6x2

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Well that’s handy! Thanks bubba
 

newguy11

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This is a great tool. It allowed me to play with rear gear ratios that complement my transmission shift points and my cams power band. Very cool
 

gmbellew

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yep, lots of calculators out there and this one is the best I've found. just be sure to use actual tire size vs the generic tire size...for example are the "33s" really 33" diameter? likely they are not, and the rolling diameter is likely a little less than the spec diameter.

example - my 33x10.5 are spec'ed at 32.5in. but the calculator is dead accurate at 32in diameter.
 

DoubleDingo

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Thanks Ray. This will definitely help some members. I have an old one from a 4x4 magazine I bought back in the 90's. I wrote down the formula and have used it numerous times to figure out what gear and tire to use. More time consuming than using a website, though. It's neat how much things have advanced or become more available through the years.
 

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