Transmission Internal Drive Ratios

[Eau Rouge]

Lots of people are running their vintage cars more and more, and using contemporary electronics in them on the track. Gearing is always an issue for many newbies and vets, alike. To get a proper gear ratio for your motor, battery, tire and chassis, it's important to know the final drive ratio of the transmission or gearbox in your buggy. Here's a list I have been compiling for a while of various final internal ratios of different buggies. I know I am missing some, so if you know of any that aren't on the list either old or new, feel free to post them and I'll update the master list in this first post.



Transmission Internal Drive Ratios

1.76:1 -- Tamiya Astute
1.86:1 -- Team Pit Stop Chain Drive
1.87:1 -- Team Associated 6-gear RC10
1.87:1 -- Team Pit Stop Chain Drive
1.96:1 -- RPM Stealth RC10 and RC10T Oval Conversion (Grey case)
2.00:1 -- Team Pit Stop Chain Drive (optional)
2.00:1 -- Schumacher Cat 2000 - Cougar 2000 - Storm 2000
2.00:1 -- MIP "Stealth"
2.04:1 -- Schumacher Cat XLS - Pro Cat (Re-release U7236 Pro transmission)
2.07:1 -- Schumacher Top Cat - Cougar (Re-release U7600 pro transmission)
2.10:1 -- Team Losi XXX4
2.14:1 -- Team Pit Stop Chain Drive (optional)
2.14:1 -- Traxxas TRX-1 - TRX-3 - TCP
2.18:1 -- Team Losi JRX2 - JRXT
2.19:1 -- Team Losi Pro SE - XX Buggy
2.20:1 -- Yokomo MR4-BX
2.21:1 -- Kyosho Lazer - Lazer Alpha - ZX-R - Triumph
2.22:1 -- A&L Lethal Weapon
2.25:1 -- Team Associated Stealth RC10 - RC10T - Dual Sport
2.28:1 -- Team Pit Stop Chain Drive (optional)
2.29:1 -- AYK Pro Radiant
2.33:1 -- Yokomo YZ10 - 870C - Works
2.40:1 -- Team Associated B2 - B3 - T3
2.43:1 -- Team Losi XXX CR
2.43:1 -- Schumacher CAT - Top Cat - Bosscat - Cougar - XL (Original or re-release standard transmission)
2.44:1 -- Tamiya DTM + 4WD
2.53:1 -- Schumacher Pro Cat
2.56:1 -- Team Losi XXX BK2 MF2
2.60:1 -- Kyosho RB5
2.60:1 -- Team Associated T2 - GT - B4 - T4 - SC
2.61:1 -- Team Losi XXT - XXT CR
2.65:1 -- RPM Stealth RC10T Conversion (white case)
2.67:1 -- Duratrax Evader SX - BX
2.72:1 -- Schumacher 98/99/Axis
2.72:1 -- Traxxas Stampede - Rustler - Bandit - Blue Eagle - LS - LS-II - SRT
2.90:1 -- TAG Coyote
3.03:1 -- Kyosho Ultima
3.79:1 -- Kyosho Ultima Re-release




(Spur gear teeth/pinion teeth) X transmission ratio = FDR

[Coelacanth]

Kyosho Optima?

[Eau Rouge]

I know which ones are missing... I obviously don't know what they are.

[askbob]

Much appreciated!

[dinglem]

AYK Pro Radiant - 2.29

TAG Coyote - 2.90

[Lowgear]

Thanks, I added them to the list since Eau Rouge isn't around to do it.

[aip47-2008]

1.86:1 -- Team Pit Stop Chain Drive

[Lowgear]

Thanks, added it.

[dldiaz]

Does anyone know the internal drive ratio for a Kyosho Lazer Alpha?

A knowledgeable person told me 2.21
Elsewhere on RC10Talk, I see where somebody estimated a Lazer ZX would be "something like 2.28"?

[GoMachV]

I trust Terry, and assuming the pulley teeth are the same as ZX which I can't imagine they would differ then it should be 14/31 so 2.21 and some change

[dldiaz]

I trust Terry, and assuming the pulley teeth are the same as ZX which I can't imagine they would differ then it should be 14/31 so 2.21 and some change

Great, Thanks!


By The Way - in looking at the transmission ratios in this thread, I came across something I never knew... AE RC10T2 has a 2.6 internal ratio??
Is that right?
That would mean the T3 went back down in ratio to 2.4, then up again to 2.6 in the T4.

[dldiaz]

I see now in the T2 manual that it is a 2.60:1 transmission.

Good to know, as I plan to start on a T2 for vintage racing soon - I have not previously built a T2.

[GoMachV]

Yeah T2 was same as GT and pretty much all the modern stuff. Weird how the ratios bounced around but motor tech was always changing I guess

[Retro rc]

Xxt and xxt-cr both have the same 2.61:1 ratio boxes
Xxt is not 2.60:1

[Retro rc]

I trust Terry, and assuming the pulley teeth are the same as ZX which I can't imagine they would differ then it should be 14/31 so 2.21 and some change

Just checked my Lazer zxr that I’m rebuilding and yes your correct 14/31
2.214:1