GY6 High Performance Koso Racing Transmission Package

Out of stock
Regular price $249.00

Get more torque and power to your wheels with the BDX High Performance Racing Transmission 



  • 150cc GY6  Engines 
  • 170cc GY6  Engines
  • BDX 175cc  Engines
  • BDX 184cc  Engines


The difference between a sluggish and slow buggy, ATV, scooter or UTV can be found in the transmission.  We have seen some great buggies, such as the Dongfang 170cc go kart.  But it is slow and sluggish because of its stock transmission. This can easily be remedied with our GY6 High Performance Racing Transmission package which includes

If you order this with an engine we install it free and you get a discounted price.



Four sets of Koso roller weights for you to optimize top end speed and low end torque of your vehicle (9g, 10g, 12g and 14 grams).  If you purchase an engine one set is included inside of your engine.

This Koso high stall clutch unit engages at higher RPM with more force than the standard clutch. This helps during steep hill climbing, towing, or when forcing the front end up over large obstacles. This unit provides a better launch from a stand still as well.

High Stall Automatic Clutch Unit

The Koso 115mm Performance Variator Included

  • 2 piece variator

  • 12g roller weights

  • Improved acceleration and hill climbing

  • Improved usage of powerband

  • Keeps you within good power range at all speeds

  • Over-sized 115mm

  • Revised Roller Ramp Angles

  • Teflon Coated Ramps

The Koso 115mm and variators are designed with steeper roller ramp angles for an improved acceleration and hill climbing. The revised roller ramp angles delay the CVT up-shifting process until the engine's powerband is reached - starting at approximately 6500rpm.

This keeps you well within good power range even at low speeds, and optimizes acceleration RPM when flooring it.

115mm Performance Variator

1500 RPM Clutch Spring

  • Extended Low Gear

  • Reduces Belt Slippage

  • Doesn't reduce top speed

  • For GY6 engine

This stiffer transmission spring keeps your CVT transmission in lower gear longer, allowing higher RPMs at lower speeds. This extends the amount of throttle you can apply at low speeds, and ultimately allowing more low-gear power to the wheels before the transmission begins to shift to higher gearing ratios. This is important for buggies where low-end power is what we're after.



Gates Powerlink Belt

This is the best quality belt for the GY6 engine.