Gearing is the cheapest speed on your kart. The same engine, same tires, same driver will run a completely different lap depending on what's on the axle and the clutch. Get it right and the kart drives off the corner and pulls down the straight; get it wrong and you're either bogging off the bottom or running out of gear before the flag stand. Here's how we think about outlaw kart gearing, track by track.
The two numbers that matter: sprocket and driver
Your final gear ratio comes from two parts working together — the rear sprocket (the big gear on the axle) and the clutch driver (the small gear on the engine). The math is dead simple:
More teeth on the rear sprocket OR fewer teeth on the driver both mean more gear — harder drive off the corner, lower top speed. Fewer teeth on the rear or more on the driver means less gear — more top end, lazier off the bottom. Rollout from your tires factors in too (a taller tire effectively takes gear away), so always think of tire size and gearing together. If you're not sure on rollout, start with our Hoosier tire size & rollout guide.
Reading the track
Tight, slick, or short tracks
Where the track is short and corner exit matters most, you want more gear — a bigger rear sprocket or smaller driver — so the kart hooks up and drives off the bottom. You'll sacrifice a little top speed you weren't going to use anyway.
Big, fast, high-bite tracks
On a longer track with a fast straightaway, gear down (smaller rear or bigger driver) so you're not bouncing off the limiter halfway down the straight. The kart will pull a little softer off the corner but carry more speed where it counts.
Rule of thumb: change one tooth at a time on the rear and re-evaluate. One tooth is a real, feelable change — don't make three changes at once or you'll never learn what did what.
Rear sprockets: #35 chain setups
Most outlaw and box stock karts run #35 chain. We stock the WMS Standard Red #35 Split Sprocket in sizes 53–57 tooth — the split design lets you swap gear at the track without pulling the axle, which is exactly what you want on race day.
#35 gear ratio chart
Use this to see how a sprocket-and-driver combo translates into a final ratio. Rows are rear sprocket teeth; columns are clutch driver teeth; each cell is the gear ratio (rear ÷ driver). A higher number is more gear (drive); a lower number is less gear (top speed). The shaded cells are combinations you can build straight from what we stock — WMS 53–57T rears and Velocity 12–20T drivers.
| Rear ↓ / Driver → | 9 | 10 | 11 | 12 | 14 | 16 | 18 | 20 |
|---|---|---|---|---|---|---|---|---|
| 53 | 5.89 | 5.30 | 4.82 | 4.42 | 3.79 | 3.31 | 2.94 | 2.65 |
| 54 | 6.00 | 5.40 | 4.91 | 4.50 | 3.86 | 3.38 | 3.00 | 2.70 |
| 55 | 6.11 | 5.50 | 5.00 | 4.58 | 3.93 | 3.44 | 3.06 | 2.75 |
| 56 | 6.22 | 5.60 | 5.09 | 4.67 | 4.00 | 3.50 | 3.11 | 2.80 |
| 57 | 6.33 | 5.70 | 5.18 | 4.75 | 4.07 | 3.56 | 3.17 | 2.85 |
| 58 | 6.44 | 5.80 | 5.27 | 4.83 | 4.14 | 3.63 | 3.22 | 2.90 |
| 60 | 6.67 | 6.00 | 5.45 | 5.00 | 4.29 | 3.75 | 3.33 | 3.00 |
| 64 | 7.11 | 6.40 | 5.82 | 5.33 | 4.57 | 4.00 | 3.56 | 3.20 |
| 68 | 7.56 | 6.80 | 6.18 | 5.67 | 4.86 | 4.25 | 3.78 | 3.40 |
| 72 | 8.00 | 7.20 | 6.55 | 6.00 | 5.14 | 4.50 | 4.00 | 3.60 |
Ratios are rounded to two decimals. Always confirm against your own tire rollout — a change in tire diameter shifts the effective gear without touching a single tooth.
Mini gears: the compact precision option
If you've spent any time in the flat kart and outlaw pits you've heard somebody talk about running "mini gears." It's worth clearing up what that actually means, because the name throws people. A mini gear setup still runs the same #35 chain as a standard sprocket — it is not a different chain pitch. What's different is the sprocket and hub system. The 4-Spoke Mini Precision Sprocket gears are a compact, lightweight gear that snaps together in two halves around a dedicated 1-1/4" mini sprocket hub, instead of bolting up like the bigger standard sprocket.
Here's why racers go to it. First, weight: the 4-spoke mini gear pulls rotating mass off the axle, and rotating mass is the worst kind of weight to carry — the engine has to spin it up out of every corner. A lighter rear gear is free acceleration. Second, precision and quick changes: the left and right halves snap together and self-center, so a gear swap at the track is fast and the gear runs true every time with no wobble. Third, tight tooth increments: the mini precision gears come in every single tooth from 40 to 64, so you can make a one-tooth change anywhere in that range without hunting for the right blank.
The trade-offs are honest ones. The mini system needs its own dedicated hub and a sized gear guard — we carry the aluminum mini gear guards in 6.75 (fits gears 40–53), 7.50 (40–60), and 8.00 (40–64), plus a carbon-fiber option — so it's a small up-front investment in the hub and guard before you're swapping gears for a few dollars apiece. And because the mini gears top out at 64 teeth, the really deep gearing for the tightest bullring tracks lives in the standard #35 sprocket range. Most racers who run mini love the light, precise feel and the fast track-side changes; racers who want maximum strength and the widest tooth range tend to stay on the standard split sprocket. Plenty of pits keep both on the trailer.
Mini gear ratio chart
Same idea as the #35 chart — rows are mini sprocket teeth, columns are driver teeth, cells are the ratio. Because the mini gears run the same #35 chain, you pair them with the same Velocity 12–20T drivers. The mini range (40–64T) leans toward the less-gear / more-top-end side, which is why it's a favorite on the bigger, faster tracks.
| Mini rear ↓ / Driver → | 10 | 12 | 14 | 16 | 18 | 20 |
|---|---|---|---|---|---|---|
| 40 | 4.00 | 3.33 | 2.86 | 2.50 | 2.22 | 2.00 |
| 44 | 4.40 | 3.67 | 3.14 | 2.75 | 2.44 | 2.20 |
| 48 | 4.80 | 4.00 | 3.43 | 3.00 | 2.67 | 2.40 |
| 50 | 5.00 | 4.17 | 3.57 | 3.13 | 2.78 | 2.50 |
| 52 | 5.20 | 4.33 | 3.71 | 3.25 | 2.89 | 2.60 |
| 56 | 5.60 | 4.67 | 4.00 | 3.50 | 3.11 | 2.80 |
| 60 | 6.00 | 5.00 | 4.29 | 3.75 | 3.33 | 3.00 |
| 64 | 6.40 | 5.33 | 4.57 | 4.00 | 3.56 | 3.20 |
Every tooth from 40 to 64 is available in the mini precision gear, so you can land on any ratio between these rows — we just stepped the chart to keep it readable.
Clutch drivers: the other half of the equation
If you run a Velocity clutch, the driver is how you make small gear changes without touching the rear sprocket. We stock Velocity Needle Bearing Drivers in 12–20 tooth so you can fine-tune the ratio with what's already on the engine. Going to a #35 setup from a different clutch? The Bully Conversion 10-Tooth Kit and 11-Tooth Kit get you converted, and the SMC 10t #35 Sprocket Conversion Kit covers Viper-based clutches.
If you're still choosing a clutch or want to understand how the Velocity 2-disc works, start with our Velocity 2-Disc Clutch buyer's guide.
Don't forget the chain
A worn or loose chain robs you of everything you just dialed in. Run a quality #35 chain like the RLV Xtreme #35 120-link chain, keep it clean, and check tension every time you change gear — swapping sprockets changes your chain slack.
Build a gear chart for your track
The fastest racers keep a notebook: track, conditions, rear sprocket, driver, tire rollout, and how the kart drove. After a few nights you'll have a cheat sheet that gets you close before you ever unload. Start with the charts above, change one tooth at a time, and let the stopwatch tell you the truth.
Need a baseline for your track?
Tell us where you race and what class, and we'll get you in the ballpark on sprocket and driver so you're not chasing gear all night. Browse our standard #35 sprockets, the mini precision gears, and Velocity drivers — or reach out and we'll help you dial it in.