Gearing Revisited

[2ndGeneration]

Did some digging thru some of my old RC literature and lo' an behold there it was in print, an article by Jack Johnson Titled " Gearing To Win " . This article was clipped from a '93 RCCA mag. In this article a glossary of gearing terms and other useful information about over and under gearing.
The best part about this article was the gearing chart, It gives conservative Final Drive Ratio starting points for several motors.

Buggies Trucks

24-Degree Stock 7.66:1 9.98:1
36-Degree Stock 8.00:1 10.40:1
45-Degree Stock 8.36:1 10.93:1
19-Turn Modified 7.08:1 9.18:1
18-Turn Modified 7.35:1 9.57:1
17-Turn Modified 7.67:1 9.98:1
16-Turn Modified 8.10:1 10.44:1
15-Turn Modified 8.60:1 10.94:1

I hope that these numbers are still somewhat valid, as I will begin to use them as a starting point.

Any comments appreciated.

[highroller]

Kinda of outdated a little now. With the increase in battery capacity so have the turns of motors changed. 19turn are generally used in spec classes and are generally like a mild mod, but gearing is similar to stock motors depending on type of vehicle and racing. Manfacturers still make machine wound motors in a variety of turns but hand wound are generally made in the 6 -14 turn range with most in the single and double range and a few offering triple winds.
Probably the best information you will find is from the vehicle or motor manufacturer which may be more up to date.

[2ndGeneration]

Yes I do see your point about going to the manufacturers, But I'm running vintage RC10t's and a RC10 CE. There just doesn't seem to be alot of information around anymore, those that were racing them seemed to have tossed any and all gearing and setup information when they upgraded their equipment. I have been floating around buying up last years and older motors to play around with.

Thanks again for your reply, If you ran the vintage goodies I would be most appreciative of any information you may still have laying around.

Again Thanks.

[highroller]

Yes I ran the older cars never owned a stadium trucks (just could never get interested in them) own the RC10 through B4 series, plus a couple of 4wd (RPS Yokomo SE, YZ10, YR4M). Hornet that was modified and raced. Had other buggies but sold them JRX, Ultima2, Traxxas TCP, Optima MidSE and RPS-C4.
Motors that I ran then were mostly Reedy Competition Stock, Trinity Monster and Joel Johnsons, Twister for modifieds the Reedy Pink and Silver Dots, Trinity and Twister motors and the 240ST Kyosho motors and battery were generally 7 cells then.
For stock spur was 81/24 for offroad, 4wd 81/23 when running on rolling skating rinks using sprint car and modified wedge bodies on 2wd buggies 81/26-28 with stock and 240ST, converted 4wd (SRP, Dominators, YZ10s, Optimas) 108 spur, 29-33 pinion (64pitch) or 81 spur 21-23 pinion in 48pitch. in modified. When we started running trucks most were made using standard RC10, JRX, Ultima conversion kits, gearing was usually 1-2 tooth less than for the buggy (if I remember right). Back then knowing the motor actual power output wasn't known, and not everyone know how gearing should be calculated. Also if you look at motors today a Epic Roar Stock is nearly making the same power (rpm levels) that a mild 17 turn motor did back in the early 80's. So when you use older vehicles with newer motors you almost need to consider where the motor is producing power and use that as a means to gear it. So today I would use a 83 or 85 spur and around a 21-23 pinion for some stock motors if tires were still 1.9. Tires ran were mostly CRP Dynamites 4211, 4212, later the Schmacher and other brands.

[2ndGeneration]

Thanks alot man,
This might actually get easier the more information I gather.

You must be the only other "old" guy on these boards :D , or just the only one that can remember that far back.

Thanks again