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Easy SCX10 III Gear Ratio Calculator

$uicide $hift

Quarry Creeper
Joined
Mar 4, 2014
Messages
224
Location
Masshole
The question about gear ratio, battery, and motor comes up often with any release. I know VoodooBrew has a nice calculator (HERE), but for those that do not have a lot of Microsoft® Excel experience it can be overwhelming.

This is a very simple Excel spreadsheet that provides the information specific to the SCX10 III only. You have the stock gearing in "Current Value" and can make changes to the "New Value". The new value is currently set with the lowest gearing I know of for this truck at this time. That is with the optional non portal transmission gear that has yet to be released.

I hope many will find this helpful and easy to use to give a clear picture of how the changes you want to make will affect your rig.

Download a copy so that you can edit the sheet with the changes you want to make.

SCX10III_Gear_Ratio_Calculator

Stock Gear Ratios (FDR):

1st Gear - 45.63
2nd Gear - 31.25
 
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There's also a super-simple-to-use gear calculator website (no need to use Excel), found here:
http://www.radiocontrolinfo.com/information/rc-calculators/rc-gear-calculator/

~ More peace, love, laughter & kindness would make the world a MUCH better place [emoji1690]

That is more simple but too simple IMO. Without motor kv, lipo cell count, and tire diameter you don't know how much difference you will see with your speed. That is great if you only want to know the gear ratio for a simple setup.

That site does not allow you to enter in each gear tooth count from transmission, transfer case, spur / pinion, differential, and portal.

This is for the SCX10 III specifically which is why I posted it in this section and not the general section. This has all of the gears listed with all of the tooth counts. You just need to enter in the "New Value" column changes you want to make and you can easily see the speed / FDR you currently are at, what speed / FDR you will end up at and the difference between the current and new values for each.
 
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Since I AM strongly considering getting the SCX10.3, I'll be downloading that spreadsheet. Just thought I'd provide that URL, as it's quite useful under 'normal' circumstances.

~ More peace, love, laughter & kindness would make the world a MUCH better place [emoji1690]
 
I remember finding that one a could months ago (when I also found the one I posted earlier), but it needed more info that what I had at that point. If you have the info, tho, I'm sure it's great.

~ More peace, love, laughter & kindness would make the world a MUCH better place [emoji1690]
 
This is fantastic. I'll be receiving my kit this coming Monday, this will help greatly. Thank you for posting it.
 

Absolutely there are other calculators out there.

This site draws a lot of people that are either new to RC or new to crawlers and I could foresee many people asking the same question but it being slightly different from the last guys question. Also not everyone knows what gears they need to get the tooth count from. And understandably some don't care, they just want to know "what will this "X" change do".

Here all of the stock gears are listed with their tooth count so everybody does not have to take the time to get all of this information and then do the math to figure out what changes they want to make for a desired result.

This is why the first word in the title is "Easy". There really is very little thought as this is specific to the SCX10 III stock gearing. A person that has ZERO knowledge in this area can grab this sheet, update what motor, pinion, battery, and tire size they run in the "Current Value" and then make changes to the "New Value" column for what they want to change and clearly see how that change will affect their MPH and FDR.
 
I hope many will find this helpful and easy to use to give a clear picture of how the changes you want to make will affect your rig.

Download a copy so that you can edit the sheet with the changes you want to make.

Nice job!"thumbsup"

Thanks for sharing!
 
I want to thank you for simply providing the raw tooth count data. Saves me from having to get out the magnifying glass and manually counting teeth on the gears. Seems I'm always ending up off by one...

Changing the gears in the transfer case looks like it has a pretty dramatic effect. 98:1 FDR is mighty low. I assume the 34 tooth gear is a Capra spur gear. Is the 20 tooth just a regular 3-gear trans input gear?
 
I want to thank you for simply providing the raw tooth count data. Saves me from having to get out the magnifying glass and manually counting teeth on the gears. Seems I'm always ending up off by one...

Changing the gears in the transfer case looks like it has a pretty dramatic effect. 98:1 FDR is mighty low. I assume the 34 tooth gear is a Capra spur gear. Is the 20 tooth just a regular 3-gear trans input gear?

^^^EXACTLY^^^ you are welcome, it can take a bit of time to collect the data and then do the math manually to see what to expect from the changes. If a person is new it takes a lot longer to research, learn, understand, and put to use.

I do not know anything about the optional transmission gear set other than what is in the manual. It states these will be available for a future release of a straight axle without portals. Losing the gear reduction from the portals will require those gears in the transmission to be changed. They basically put a transfer case between the transmission and the dig / 2 speed gears.

If you use the straight axles with the optional transfer case gear set and the stock 14T pinion the gear ratio is 40.48:1 in first gear.

Some guys like to run really high gear ratios with lots of power and I can see people keeping the portals and using the optional gear set for some serious torque to the wheels. Others are not fans of portals but love the truck so they may go the route of the straight axles and without that gear change the truck would be really fast.

*EDIT*

No need to manually count the gear teeth. In the manual for each step the diagrams list the gear part number and how many teeth it has. The numbers I used were direct from the manual. So if the manual is wrong I am too!
 
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Great work! Thank you for sharing.

People are referring to other gearing calculators, but they are missing the point. This is very specific to the SCX10 III and you took all the guesswork out of it. Nice job! "thumbsup"


Can someone edit the first post to state CLEARLY what the stock ratios are for 1st and 2nd?

Thanks.

Did you happen to look at the link. It's as clear as day on there.
 
Great work! Thank you for sharing.

People are referring to other gearing calculators, but they are missing the point. This is very specific to the SCX10 III and you took all the guesswork out of it. Nice job! "thumbsup"




Did you happen to look in at the link. It's as clear as day on there.

Sure did. Since this is a searchable topic and something that will come up frequently seems like someone should say:

First gear ratio ~45:1
Second gear ratio ~31:1


But I suppose they can scroll down to my post to find it.

Thanks for the insightful response.
 
Sure did. Since this is a searchable topic and something that will come up frequently seems like someone should say:

First gear ratio ~45:1
Second gear ratio ~31:1


But I suppose they can scroll down to my post to find it.

Thanks for the insightful response.

I think I can see where your mind was at. You were searching for what the FDR was and this post came up. When you did not see it listed you inquired about it as you were not looking for a gear ratio calculator, but rather you just wanted to know what the stock FDR was.

In case somebody else is searching for stock FDR for the SCX10 III and they land on this post I have added that so that it is at the top.
 
I think I can see where your mind was at. You were searching for what the FDR was and this post came up. When you did not see it listed you inquired about it as you were not looking for a gear ratio calculator, but rather you just wanted to know what the stock FDR was.

In case somebody else is searching for stock FDR for the SCX10 III and they land on this post I have added that so that it is at the top.

You got it, thanks. Until Axial puts up the ratios for both gears that information will have to live under this thread!
 
The question about gear ratio, battery, and motor comes up often with any release. I know VoodooBrew has a nice calculator (HERE), but for those that do not have a lot of Microsoft® Excel experience it can be overwhelming.

This is a very simple Excel spreadsheet that provides the information specific to the SCX10 III only. You have the stock gearing in "Current Value" and can make changes to the "New Value". The new value is currently set with the lowest gearing I know of for this truck at this time. That is with the optional non portal transmission gear that has yet to be released.

I hope many will find this helpful and easy to use to give a clear picture of how the changes you want to make will affect your rig.

Download a copy so that you can edit the sheet with the changes you want to make.

SCX10III_Gear_Ratio_Calculator

Stock Gear Ratios (FDR):

1st Gear - 45.63
2nd Gear - 31.25


Great job"thumbsup"

Is it o.k. for you if i post that excel sheet in the german rockcrawler.de forum?

Thx
 
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