When you’re in need of an engine with some serious power, the BBR Tuning Stage 4 Performance Engine Kit is the engine kit for you. With this performance package, you’ll get everything you need to get tons of power, from top-end speed to bottom-end torque. Outfitted with an Expansion Chamber for a smooth ride, and NGK spark plug and a high-performance head for major compression, and a high-performance carburetor for optimum speed, you’ve got a motor that’s ready to perform and more importantly, a motor that’ll last.

The Smoothest Running Engine You’ve Ever Felt

With an Expansion Chamber on this motor you can count on a smooth ride. Ever wonder why it feels so rough when you ride? That’s partially because the stock muffler restricts airflow coming out of your engine, and if you’re using performance parts you’ll need something that won’t limit your motor from expelling all that exhaust it creates.

Enter the Expansion Chamber. With no baffle in the chamber, there’s nothing limiting airflow except at the exhaust port. However, the banana shape of this muffler helps circulate air around the chamber so that instead of a large amount of smoke trying to go through a small hole, there’s a smooth flow of air coming from the chamber itself. Not only will you get a little bit of torque of this muffler, but you’ll also get a smoother ride, too.

Unlock This Engine's True Power With a High Performance Carburetor

With the BBR Tuning 2-Stroke 66/80cc High-Performance Carburetor on this racing engine, you’ll drastically increase airflow and fuel delivery for more power, speed, and even better fuel efficiency. Its 78mm jets are especially perfect for racing, and the best part: this carburetor needs no adjusting. Just install the carb, fire the engine up, and in minutes you’ll feel increased acceleration and torque.

Compression of a Performance Motor with the Carburetor to Back it Up

With the BBR Tuning High Performance head leading the way, this engine will give you more compression than ever. More compression means an increase in speed and pulling power, so not only will you go faster but those hills and inclines won’t give you a problem anymore. And if that wasn’t good enough, its tall heat syncs let your engine cool faster, letting your ride longer than ever.

Add to that the High Performance Carburetor, and you’ve got yourself a speed machine. Its bigger jets will give your engine more fuel, and its air filter will let your carburetor breathe better than ever. You’ll definitely need a performance carburetor if you’re looking to run a high performance head, and we made sure that this BBR Tuning package had that standard.

The Spark Plug Dream Team Included

What would a performance engine be without a high quality CDI? If you’re giving your engine more fuel it needs a better spark than your stock CDI will give it. The Stage 1 CDI included with this package was made for performance, with its high performance wire that offers you better connectivity than ever and a high quality Japanese NGK spark plug cap.

Standard spark plugs can’t handle all that performance quite well, so we paired this CDI with an NGK BR5HS spark plug that’ll give you the best, most consistent spark you’ve gotten out for your engine in quite some time.

*Note: Gasoline operated products are NOT compliant with Environmental Protection Agency ( E.P.A. ) or California Air Resources Board (C.A.R.B) for the use on/off Public roads. Upon purchase, the buyer agrees to use products for racing (closed-course competition) only and NOT for on/off public roads.

Installation is a breeze! The rider only needs some basic hardware skills, tools, and around 2-3 hours for installation and fine tuning adjustments (Note: Seller is not responsible for misuse or this kit or any warranty after installation).

Assembly of engine and motorized bicycle required. Click here for instructions

Product Requirements

Fits Most 26" Wheeled Bikes (Mountain, Cruiser, Chopper, Road) with V-frame. The frame should have 9-11” of clearance between the bottom bracket and top bar, and the diameter of the frame tubes should be 25-29mm (around an 1”).

** Also note: Sprocket Clamp Assemblies included with BBR Tuning 2-Stroke 48cc and 66/80cc, and 4-Stroke 49cc bike engine kits come with only 1x set of metal plates. Older production of these assemblies included 2x sets, but from testing and redesigning, existing engine kits and engine kits in the future will only require 1x set. This redesigned assembly helps secure your rear wheel sprocket better than in previous production.

1. Silver BBR Tuning 66/80cc 2-Stroke Engine
2. Bonus- BBR Tuning Billet Aluminum High-Performance Cylinder Head 66/80cc
3. Bonus - 66/80cc High-Performance Carburetor
4. Bonus – Expansion Chamber, Expansion Chamber with Muffler, or High Performance Expansion Chamber
5. Bonus - NGK BR5HS Spark Plug
6. Complete Clutch Cable Assembly with Clutch Wire Clip
7. Drive Chain Idler Pulley
8. Top Quality Japanese 202 Main Bearings
9. 415 Bike Engine Drive Chain
10. Drive Chain Guard
11. 2-Stroke Spark Plug
12. Locking Alloy Clutch Lever
13. Upgraded Twist Throttle and Cable With Grip
14. Updated 1.5L Black Teardrop Gas Tank (approx. Γàû of a gallon)
15. Fuel Line
16. Throttle Cable
17. Gasoline Tank Switch
18. Sprocket Clamp Assembly
19. 44 Tooth Chrome Drive Sprocket with 9 Holes
20. Large Spring (Heat Shield Spring)
21. Extension Spring (Recoil Spring)
22. High-Quality Japanese Bearings on Both Ends of Crank
23. Required Hardware and Gaskets
24. Magneto
25. Kill Switch
26. Complete Digital Installation Guide
27. Spark Plug Removal Tool (While Supplies Last)!
28. Standard Universal Mounting Bracket

The BBR Tuning 66/80cc Stage 4 Race Series bike engine kit is about 9" height 7" length 5" width. The bike engine kit fits on standard, male frames with tubing of 25mm to 29mm in diameter. Larger frame sizes require drilling into bike frame with a stationary bolt and use the universal face plate to mount the front of the engine.

• 2.75+ HP (horse power)
• 25 to 40 mph depending on the gear ratio and weight
• Fuel Economy: 100-125 miles per gallon

Disclaimer: Operating a motorized bicycle and/or bicycle engine kit carries a risk of serious bodily injury. The rider accepts responsibility for any and all vehicle operation that may lead to personal injury, economic loss, social distress, other losses, costs and damages. BikeBerry.com is not responsible for injuries and/or damages resulting from operating this motorized bicycle or bicycle engine kit.

Disclosure of accurate engine size: While we have chosen to use the long standing factory branding engine size of "80cc", the true displacement of the bicycle engine is 66cc. Down through the years China bicycle engine manufactures have advertised their biggest engine as 80cc, therefore we have listed them in the same way on our website. However, the bore and stroke of an 80cc being 47x38mm equals 66cc. Therefore the true displacement of the 80cc bike motor is 66cc. In the west, the volume of a cylinder is calculated by using the formula Volume = Pi x Radius Squared x Stroke. However, in the east the displacement of an engine includes the area of the cylinder head's combustion chamber as well as the volume of the cylinder. Therein lies a discrepancy between measuring standards by the manufactures in China with those in the United States. However, all "80cc" engine kits on the market today are actually 66cc in displacement size if measuring by US standards.

BBR Tuning Engine Kits require a pre-mixed fuel ratio of 40:1 (3.2oz of oil to 1 gallon of gas)

• Recommended Gas Grade: 87 Octane
• Recommended Oil: Maxima Scooter Pro 2-Stroke Synthetic Motor Oil 1 Liter