RPM Drop Between Gearbox Ratios

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Jerry Poole
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RPM Drop Between Gearbox Ratios

Post by Jerry Poole » Sun Feb 01, 2015 5:06 am

Could anyone from the forum please direct me to a site or formula that calculates the RPM Drop that would occur with different gearbox ratios ? I have a gearbox, 5 speed , that allows me to change ratios for each forward speed and would like to know what the RPM Drop that would occur with each ratio change at any RPM. Thanks for any information and input. Jerry

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John Wallace
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Re: RPM Drop Between Gearbox Ratios

Post by John Wallace » Sun Feb 01, 2015 9:19 am

See if this helps?

RPM After Shift Calc

:)
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Brian P
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Re: RPM Drop Between Gearbox Ratios

Post by Brian P » Sun Feb 01, 2015 9:57 am

Take the upshift RPM, divide by the gear ratio of the gear that you are shifting out of, multiply by the gear ratio of the gear that you are shifting into.

Very easy to make up a little spreadsheet that you can plug all your ratios into.

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Re: RPM Drop Between Gearbox Ratios

Post by iadr » Sun Mar 08, 2015 3:48 pm

In my opinion the absolute best:

http://www.cargister.com/calculator-gear-ratio

Perhaps a link to an example best shows it (best way is to cut the rest of the address and paste*after* arriving at the site):

http://www.cargister.com/calculator-gea ... =&teeths[2][]=

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Re: RPM Drop Between Gearbox Ratios

Post by Kenova » Sun Mar 08, 2015 8:54 pm

Over the hill but still learning!
Retaining it is the hard part.

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Re: RPM Drop Between Gearbox Ratios

Post by pdq67 » Thu Mar 12, 2015 10:33 pm

I have a old disc copy of MrG/Motion's Drag sim program that allows playing with tranny gears. Probably out of date since it is MSDos??

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Re: RPM Drop Between Gearbox Ratios

Post by F-BIRD'88 » Wed Apr 01, 2015 4:40 pm

pdq67 wrote:I have a old disc copy of MrG/Motion's Drag sim program that allows playing with tranny gears. Probably out of date since it is MSDos??

pdq67
If you want to run your old DOS computer programs on a new recent computer
get and install "DOSBOX" on your computer and run it under dosbox.

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John Wallace
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Re: RPM Drop Between Gearbox Ratios

Post by John Wallace » Thu Apr 02, 2015 9:00 am

Is the old program on a floppy disk? (not cd disk)

You would need to find a new computer with a floppy disk drive?

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Re: RPM Drop Between Gearbox Ratios

Post by pdq67 » Thu Apr 02, 2015 9:10 pm

Thanks John for your help.

pdq67

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