Single Speed Gearing
 

I have a single speed on a stock chassis and want to run the 9920 with a 8xl on 5s. I tinkerd with the "motor selector" and "Random Parameter Solver" and found that an 8xl with 5s and 18/54 gearing is "good" for a for a top speed of +/- 40mph, 20/54 for 45mph and 22/54 for 50mph without any overheating warnings.
Does this sound about right to you guys?

what pitch? 32?

It sounds like you got some short tires. It sounds right though depending on tire
height.

It sounds about right but maby + or - depending on the weight and tire size

Yeah I figured 32p but the calculators did not have an option to select what pitch.

Yeah right now I have maxx mashers (not 40's).

Here are the variables I entered:
Enter approximate vehicle weight: 12 lbs (is this abought right)
Enter the differential gear ratio: 2.846... Revo
Enter the transmission gear ratio: 1.722... E-Maxx 2nd gear
Enter the battery voltage you plan to use: 18.5 5cells 3.7/cell
Enter tire diameter in inches:5.5

where can you get a 54th 32 pitch spur? I thought they were mod 1 when they went that low..lmk
phil

Jato

Actually, I have some of these spurs I believe...Not sure, but I think there for the Nitro Hawk...

Is 12lbs a good estimate for thw weight of a BL Revo with a stock chassis?

12lbs is definitely a safe figure. Mine weighs less than 11lbs with 14 GP cells. My first version (using the emaxx tranny) weighed something like 13 lbs IIRC.

I was close...

When I said "Jato", I was assuming a gear that was compatible with the Revo slipper (with no mods)...

Cool! I think im all set to make my final purchases to complete my project. Oh, Im so excited! :D
Yeah, Nitro Hawk gears are the next smallest of the 32p spurs that traxxas makes that use pegs/diffballs.

Does the revo slipper fit the shaft on a e-maxx tranny?

No, it doesn't, but a adapter of sorts is on its way...

one more question with a spur that small does the pinion match up ok? mine on 18/66 is about out of adjustment. (motor hits the tranny) (E-maxx though)
phil

Good catch, diddnt even think of that.

If the total sum of the diameters of your gears is 70.4mm (18t = 16mm + 66t 54.4mm according to the “gear calc”), then the sum of the diameter of each gear should be equal to or greater than 70.4mm in order to for the gears to mesh properly. Is that right? :013:

If so, 22/54 wouldn’t reach, only adds up to 64mm. The smallest spur I could use with a 22t pinion would be a 62t. Maybe I’ll hold of on buying a motor and pinions until I get a better handle on the whole gearing thing.:002: