First time with a brushless car...

[RC104ever]

I think the issue here is gearing - I run a 23 / 81 combo with a Castle 5700 / Mamba setup and have had zero issues in HARD bashing with my stock stealth tranny. Heck, even the 6 gear lasted for awhile before the idler gears crapped out. I'm also running it on pavement but I'm using 2.2" wheels and tires so that could account for some of the difference.

[JK Racing]

sounds like a combination of bad gearing (19/90 is way too low) and the smaller buggy tires.

the motor is a 3800 KV, when I ran my slash (as a slash ), I ran a 4600 KV castle motor geared 24/86, still had plenty of torque and low end grunt to pull the front end up 1/2 way down the straight away when I felt comfortable to squeeze the trigger all the way. Also...the stealth is a 2.25 ratio, the slash is 2.72 ratio. What gearing were you running on the stealth? Using that info we can figure out what gears to run to match the speed you used to have.

[Dave145]

I was running 23/87 on the stealth. I have pinions as low as 17 teeth and as big a 30 teeth. I have spurs as low as 81 and as big as 87. Right now I'm testing the 6 gear tranny that should be more durable with an all metal drivetrain. What ratios should I use for both the first gen stealth and the 6 gear tranny?

[JK Racing]

Stealth tranny is 2.25

• 87/23*2.25=8.51 FDR

Slash tranny is 2.72

• 87/28*2.72=8.45 FDR

6 gear is 1.85

• 87/19*1.85=8.47 FDR

every 3 teeth on the spur gear - 1 tooth on a pinion:

• 87/23 is essentially the same as 84/22, 81/21, 78/20

[Dave145]

so those ratios would yield a good amount of both torque and speed? I'm looking to go fast (even on a 7 cell nimh battery from a year ago), but still have enough torque to get me through medium length grass at top speed and (maybe?) pull a wheelie or two. Is this possible in a 4.5 pound car without overheating the motor or esc?

[JK Racing]

if you were originally doing that with the stealth, the other ratios I posted are near identical, a touch taller (lower punch and slightly higher top end).

A lower FDR - more top speed
A higher FDR - less top speed

[Dave145]

Dumb question: Any idea how fast the car will go with the FDR for the 6 gear? (I'm hoping for around 30-40mph) Is that possible? What about speed on a baseball diamond?