Yerf Dog Spiderbox & Crossfire Internal Reverse Engine Upgrade Package, 150cc, 175cc

  • $849.00
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Finally you can step up your Yerf Dog or yellow Crossfire to be like all up to date buggies.  We have developed a bolt-in package for a reverse engine for your Yerf Dog Spiderbox. or yellow Crossfire  This is the standard GY6 internal reverse engine that comes on all new buggies.  You have several options with this package:

Option 1 - 150cc GY6 Internal Reverse Engine with Machined Axle

  1. The GY6 internal reverse engine. This is a standard GY6150cc engine with engine sprocket and nut.. 
  2. A reverse shifting package to change from forward to reverse. The shifting package included two shifting cables, shift handle and other hardware to change gears.
  3. Machining and welding of your old axle. In order to get your axle sprocket to line up with the engine sprocket, you'll send us your axle and we will cut the weld on your axle and move the sprocket hub location over and re-weld.

Option 2 - 175cc Internal Reverse Engine with Machined Axle

  • 175cc internal reverse GY6 engine with the upgraded transmission with the 1500RPM yellow spring, the high stall clutch and the performance variator.  Includes engine sprocket and nut.
  • Machining and welding of your old axle. In order to get your axle sprocket to line up with the engine sprocket, you'll send us your axle and we will cut the weld on your axle and move the sprocket hub location over and re-weld
  • Machining and welding of your old axle. In order to get your axle sprocket to line up with the engine sprocket, you'll send us your axle and we will cut the weld on your axle and move the sprocket hub location over and re-weld.

Option 3 - 150cc Internal Reverse Engine with New Heavy Duty Axle and Hubs

  1. The GY6 internal reverse engine. This is a standard GY6150cc engine with engine sprocket and nut.
  2. A reverse shifting package to change from forward to reverse. The shifting package included two shifting cables, shift handle and other hardware to change gears.
  3. You get a new heavy duty replacement axle, bearings, axle bearing hubs and rear wheel hubs.

Option 4 - 175cc Internal Reverse Engine with Machined Axle

  • 175cc internal reverse GY6 engine with the upgraded transmission with the 1500RPM yellow spring, the high stall clutch and the performance variator.  also includes engine sprocket and nut.
  • Machining and welding of your old axle. In order to get your axle sprocket to line up with the engine sprocket, you'll send us your axle and we will cut the weld on your axle and move the sprocket hub location over and re-weld
  • You get a new heavy duty replacement axle, bearings, axle bearing hubs and rear wheel hubs.

BDX 150CC GY6 ENGINES ARE GUARANTEED, VERIFIED AND CERTIFIED:

If you are considering purchasing a GY6 engine from eBay, Amazon or any other USA seller you could receive a 125cc engine instead of a 150cc and you would never know it.  The engines look identical from the outside.  BDX Performance is the only engine seller in the USA who disassembles and visually inspects engines to ensure that they are 150cc.  We unbox and dissemble approximately 50% of every engine shipment that we receive as we convert these into 175cc engines.  And we have caught some engines that are GY6 125cc being sold as GY6 150cc.  Don't play Russian roulette with your money.  Get a guaranteed, verified and certified GY6 engine from BDX.  The cylinder on the left is an actual cylinder that we pulled off of an engine that we purchased as a 57mm GY6 150cc engine and was actually a 52mm GY6 125cc engine.