Best Gearbox For Go Kart: 10 Forward-Reverse Options Compared

#1 · Best Overall

1. VEVOR 30 Series Gearbox

• Weight: 12 lb
• Dimensions: 5.5 x 4.33 x 8.34 in

Best for: Rustproof 30 Series versatility.

Why it ranks #1: Its 2–13HP fit, 5/8-inch shaft and 3/16-inch keyway suit common builds, with sprocket options for #35 and #40/41/420 chain.

VEVOR specifies rustproof metal and three shift modes, giving a 30 Series kart operator forward, reverse, and neutral selection in a gearbox described for durable use. Its 5/8-inch shaft and sprocket choices for two chain families make the drive setup more clearly defined.

The 5/8-inch shaft with a 3/16-inch keyway provides the listed interface dimensions, and the 12-tooth #35 or 10-tooth #40/41/420 sprocket choices let builders match either named chain arrangement. Forward ratio is 1:1.3, reverse is 1:2.6, and RPM is listed as 2300. Rustproof metal is cited as a durability feature, while three shift modes support more maneuvering options. VEVOR lists 2–13HP fitment in verified facts and describes installation for DIY kart assembly.

Skip it if you require one consistent engine-range specification before selecting a gearbox; maXpeedingrods YW65 states a clear limit of up to 14HP.

This suits a DIY 30 Series build needing three shift positions and either listed chain setup. Weigh its rustproof-metal claim and clear shaft details against the conflicting engine-range information.

Listed on Amazon as: VEVOR Go Kart Forward Reverse 212cc Gear Box, 30 Series Torque Converter, 10T #40/41 12T #35 Go Karts Accessories TAV2 30 40 41 for 2HP-13HP Engine, Transmission Local Honor, 3 Shift Modes

#2 · Best Engine Range

2. maXpeedingrods 30 Series Kit

• Weight: 12.35 lb
• Dimensions: 7.87 x 7.87 x 7.87 in

Best for: 30 Series chain flexibility.

Why it ranks #2: The 30-series kit is listed for engines up to 14HP and includes both 12-tooth #35 and 10-tooth #40/41/420 sprockets.

Included 12-tooth and 10-tooth sprockets let this maXpeedingrods gearbox accommodate either #35 chain or #40/41/420 chain, giving a 30 Series kart builder a choice of listed chain setups. It supports engines up to 14HP and provides forward and reverse operation for go-karts and utility vehicles.

The 5/8-inch shaft with 3/16-inch keyway specifies the connection point for the compatible 30 Series installation, while the 1540mm shifter cable provides a stated cable length for positioning the shifter. Forward ratio is 1:1.3 and reverse is 1:2.6; the gearbox speed is 5/13 of clutch speed. With both chain sprockets included, buyers can select the listed chain option without sourcing that sprocket separately. The 14HP ceiling and 30 Series restriction define the appropriate application.

Skip it if you need a 40 Series gearbox for an 11–18HP engine; Leyuncot's 40 Series kit lists that engine range.

Choose this for a 30 Series go-kart or utility-vehicle build up to 14HP where either listed chain size is useful. Its boundary is clear: it is specified only for 30 Series, not 40 Series installations.

Listed on Amazon as: maXpeedingrods Go Kart Forward Reverse Gearbox Kit 212cc 30 Series

#3 · Broad Chain Fit

3. GXYWADY 2–13HP Gearbox

• Weight: 12.45 lb
• Dimensions: 7.87 x 7.87 x 7.87 in

Best for: Broad 30 Series engine range.

Why it ranks #3: This 30-series replacement covers 2–13HP engines and specifies 12-tooth #35 or 10-tooth #40/41/420 sprocket options.

A stated 2–13HP engine range gives this GXYWADY gearbox unusually broad listed coverage within 30 Series applications, from smaller engines through 212cc setups. Forward, reverse, and neutral modes add maneuvering choices, while included sprockets serve two named chain arrangements.

The 5/8-inch shaft with 3/16-inch keyway defines the connection specification, and the listed 12-tooth #35 and 10-tooth #40/41/420 sprockets let buyers match either stated chain family. Three shift modes—forward, reverse, and neutral—support maneuvering beyond forward-only operation. It is specified for four-stroke engines from 2HP to 13HP and works with a 30 Series torque converter. The package listing also mentions mounting hardware, though the supplied details do not fully enumerate its contents.

Skip it if you need a 40 Series gearbox for an 11–18HP engine; GXYWADY's 40 Series replacement lists that higher range.

Choose this for a four-stroke, 30 Series build within 2–13HP that benefits from three shift positions and either listed chain option. Its torque-converter series and engine type limit the fit.

Listed on Amazon as: GXYWADY Forward Reverse Gearbox Kit Replacement for 2HP-13HP Go Kart

#4 · Clear Shift Modes

4. Silscvtt 30 Series Gearbox

• Weight: 12.35 lb
• Dimensions: 11.81 x 10.24 x 7.87 in

Best for: 30 Series neutral control.

Why it ranks #4: It specifies forward, reverse and neutral, a 5/8-inch shaft, and a 1540mm shifter cable, while explicitly warning it will not fit 40 series.

Three positions—forward, reverse, and neutral—make the Silscvtt gearbox useful when a 30 Series kart needs both reverse maneuvering and a neutral setting. It lists support for engines up to 13HP, a 5/8-inch shaft, and sprocket options for two chain families.

The 5/8-inch driven-clutch shaft with a 3/16-inch keyway supplies the key interface dimensions for evaluating installation, while the 1540mm shifter cable gives a stated length for arranging the control. Forward and reverse ratios are 1:1.3 and 1:2.6, with a listed 2300 RPM specification. Sprocket compatibility covers 12-tooth #35 chain or 10-tooth #40/41/420 chain. The kit is explicitly for 30 Series only, making that restriction important when matching a drivetrain.

Skip it if you need a 40 Series gearbox for a 420cc engine; Leyuncot's kit lists 40 Series fitment for that application.

This fits a 30 Series kart builder who values neutral and needs one of the two listed chain arrangements. Keep its 13HP ceiling and explicit exclusion of 40 Series installations in view.

Listed on Amazon as: Silscvtt 30 Series Go Kart Forward Reverse Gearbox

#5

5. ALL-CARB 30 Series Gearbox

• Weight: 12.28 lb
• Dimensions: 7.09 x 7.09 x 7.09 in

Best for: 30 Series cable-length choice.

Why it ranks #5: Its 5/8-inch shaft, 3/16-inch keyway and 1:1.3 forward ratio are clearly specified for 2–13HP engines and 30-series applications.

A 130cm shifter cable distinguishes this ALL-CARB gearbox from listings that state a longer cable, giving builders a concrete control-cable dimension to consider. Its 5/8-inch shaft, 3/16-inch keyway, and three shift positions suit listed 2–13HP 30 Series applications.

The 5/8-inch shaft and 3/16-inch keyway specify the gearbox interface, while 10-tooth #40/41 and 12-tooth #35 sprocket options support the two listed chain setups. Forward and reverse ratios are 1:1.3 and 1:2.6, with a stated 2300 RPM. The 130cm shifter cable gives buyers a defined length to account for when routing controls. It is described for engines from 2HP to 13HP and for go-karts, utility vehicles, and other off-road vehicles.

Skip it if you need the stated 1540mm cable length; Silscvtt's 30 Series gearbox lists that cable dimension.

This suits a 30 Series builder within 2–13HP who can work with a 130cm shifter cable and needs either listed chain option. Account for that cable length when planning control routing.

Listed on Amazon as: ALL-CARB Go Kart Forward Reverse Gearbox Replacement for 2HP-13HP

#6

6. labwork 30 Series Kit

• Weight: 5600 g

Best for: 30 Series assembly dimensions.

Why it ranks #6: This 30-series 2–13HP option lists 5/13 clutch-speed gearing, a 1540mm shifter cable and replacement sprocket sizes for common chains.

A 1540mm shifter cable gives the labwork gearbox a specific control length for builders planning a 30 Series kart assembly. It is listed for 2–13HP four-stroke engines and 2300 RPM, with replacement sprocket options covering 10-tooth 40/41 and 12-tooth 35 chain setups.

The gearbox speed is stated as 5/13 of clutch speed, which gives builders a defined speed relationship for planning the transmission. A 1540mm shifter cable supplies a concrete dimension for routing the shift control, while the listed 10-tooth 40/41 and 12-tooth 35 sprockets identify two chain arrangements. The kit is described as easy to install for kart assembly and is specified for 2–13HP four-stroke engines in a local 30 Series setup. Its stated 2300 RPM further defines the listed operating specification.

Skip it if you need a 40 Series gearbox for a Predator 420cc engine; Leyuncot's 40 Series kit lists that fitment.

This fits a 30 Series assembler working within the stated 2–13HP four-stroke range who needs the listed cable length and chain options. Keep its series and engine limits central to the drivetrain choice.

Listed on Amazon as: labwork Go Kart Forward Reverse Gearbox Kit Replacement for 2HP-13HP Engine

#7

7. JNDO 30 Series Gearbox

• Weight: 12.1 lb

Best for: DIY three-mode maneuvering.

Why it ranks #7: It offers forward, neutral and reverse for engines up to 13HP, but the supplied details do not specify shaft dimensions or chain options.

Forward, neutral, and reverse modes give the JNDO gearbox a practical answer to a go-kart's missing reverse function, helping drivers reposition without relying on forward-only movement. Its listed engine support reaches 13HP and 420cc, making this a 30 Series option for builders seeking more maneuverability.

The three shift modes let a driver choose neutral as well as forward and reverse, supporting more controlled operation when maneuvering a kart. JNDO lists compatibility with engines up to 13HP (420cc), so buyers can assess the kit against a stated power ceiling rather than assume it suits every engine. Its 30 Series designation narrows the intended setup, and the DIY-assembly description makes it relevant to builders adding reverse functionality themselves. The supplied information does not specify shaft or sprocket dimensions.

Skip it if you need stated shaft and chain dimensions before choosing; maXpeedingrods YW65 specifies a 5/8-inch shaft and two chain sprockets.

This suits DIY builders adding forward, neutral, and reverse to a 30 Series kart within the listed 13HP and 420cc limit. Check the available specification detail against your installation needs before committing.

Listed on Amazon as: JNDO Go Kart Forward Reverse Gearbox Kit 30 Series for 212cc 420cc Engine

#8 · Best 40-Series Fit

8. Leyuncot 40 Series Kit

• Weight: 23.1 lb

Best for: 40 Series heavy-engine fit.

Why it ranks #8: Its 3/4-inch shaft, 3/16-inch keyway and 530-chain sprocket target 11–18HP builds, including Predator 420CC applications.

Predator 420cc and Duromax 11HP-and-above fitment put this Leyuncot gearbox squarely in the 40 Series, higher-powered replacement category. Its listed 3/4-inch intermediate shaft, 530 chain, and 12-tooth sprocket give builders concrete drivetrain details for assessing a go-kart or utility-vehicle installation.

The 3/4-inch intermediate shaft with a 3/16-inch keyway establishes the specified shaft interface, and the 12-tooth sprocket with 530 chain identifies the drive arrangement. Those details help a builder compare the kit with a 40 Series drivetrain rather than treating it as a universal gearbox. Leyuncot lists an 11–18HP engine range, including Predator 420cc and Duromax 11HP-and-above applications, as well as go-karts and utility vehicles. Forward ratio is 1:2 and reverse is 1:2.6; the description does not list alternate chain sizes.

Skip it if you need a 30 Series gearbox with both chain options; maXpeedingrods YW65 includes sprockets for #35 and #40/41/420 chain.

This is a fit for 40 Series builders using the listed 11–18HP engine range and 530-chain arrangement. Its 3/4-inch shaft and stated chain setup define the boundary for a compatible drivetrain.

Listed on Amazon as: 40 Series Forward Reverse Gearbox 11-18hp Fit for Predator 420CC 530 chain

#9

9. GXYWADY 40 Series Gearbox

• Weight: 20.8 lb

Best for: 40 Series 420cc replacement.

Why it ranks #9: This 40-series option specifies an 11–18HP fit, 3/4-inch jackshaft and 12-tooth 530-chain sprocket for larger-engine applications.

A 3/4-inch jackshaft and 12-tooth sprocket for 530 chain make the GXYWADY gearbox a clearly specified 40 Series replacement for higher-powered kart setups. It lists fitment for 11–18HP engines, including Predator 420cc and Duromax 11HP-and-over applications, and supplies forward and reverse ratios.

The 3/4-inch jackshaft with 3/16-inch keyway identifies the mounting shaft specification, while the 12-tooth sprocket and 530 chain define the listed drive-chain arrangement. That combination helps buyers assess compatibility for the stated 40 Series and 13–18HP go-kart, utility-vehicle, and other applications. Forward ratio is 1:2 and reverse is 1:2.6, giving concrete transmission information for planning operation. Predator 420cc and Duromax 11HP-and-over fitment are also named; chain alternatives are not listed.

Skip it if you need a 30 Series setup with #35 or #40/41/420 chain; VEVOR's gearbox lists those chain choices.

Choose this for a 40 Series build in its stated engine range, especially one using a 3/4-inch jackshaft and 530 chain. Its listed chain setup is specific, so other chain arrangements are not established here.

Listed on Amazon as: GXYWADY 40 Series Forward Reverse Gearbox Replacement for Go-Karts

#10

10. Blast 40 Series Gearbox

• Weight: 22 lb

Best for: 40 Series clutch-free kit.

Why it ranks #10: It targets 11–16HP engines with a 3/4-inch jackshaft, but the listing says driver and driven clutches are not included.

The Blast gearbox is explicitly sold without driver or driven clutches, a key planning detail for builders assembling a 40 Series drivetrain from separate components. Its 3/4-inch jackshaft and listed 10-tooth 420-chain sprocket target heavier 11–16HP applications, including Predator 420cc setups.

A 3/4-inch jackshaft with 3/16-inch keyway gives the stated shaft interface, while the selected 10-tooth sprocket is listed for 420 chain; a 12-tooth sprocket with 530 chain is also mentioned. The 11–16HP feature range and 11–18HP description both position it for higher-powered applications, with Predator 420cc among the named fits. Because neither driver nor driven clutch is included, buyers must account for those separate components when planning the complete installation.

Skip it if you need a gearbox kit that includes driver and driven clutches; labwork lists a 30 Series gearbox kit without that exclusion.

Choose this for a higher-powered 40 Series project where clutches are already available or will be sourced separately. Its 3/4-inch jackshaft and chain choices should guide the drivetrain match.

Listed on Amazon as: Go Kart Forward Reverse Gearbox Kit Compatible with 11-16 hp Engines, Predator 420CC- 3/4" jackshaft (10T Sprocktet 420 Chain)