Engine Sprocket
We have several rear sprocket options available for our clients to “good tune” their gas operated bicycle to achieve their desired optimal velocity/power gear ratio.
A note to remember: The larger the rear sprocket, the slower the bike will go, but will have capacity to climb hills. Small the rear sprocket, the quicker the bike will move, but will climb hills less successfully. You are trading power for speed or vice versa.
You can expect sizes of 36 tooth, 44 tooth, 48 tooth, and 56 tooth sprockets in the Large 9-hole gear. The internal diameter is usually 1.4″, hole spacing is 1″. See table below for specs. Commonly, the large 9-hole sprocket with 48 tooth configuration will come with the 4G T-Belt Drive 4-stroke engine kit.

Rear Sprocket (Large 9 Hole) Hole Spacing Internal Diameter Outer Diameter Top Speed Acceleration/Power Included With
36 Tooth 1″ 1 13/32″ 5 7/8″ Fast Low Sold Separately
44 Tooth 1″ 1 13/32″ 7″ Moderate+ Moderate- Sold Separately
48 Tooth 1″ 1 13/32″ 8 1/8″ Moderate- Moderate+ 4G T-Belt
56 Tooth 1″ 1 13/32″ 9″ Sluggish High Sold Separately

The tiny 9-hole sprockets can be found in two sizes, 44 tooth and 50 tooth. The internal diameter is certainly 1.39″ and hole spacing is 1″. See table below for specs. The tiny 9-hole 44 tooth sprocket should come with the SkyHawk Position Fire 2-stroke engine kit.

Rear Sprocket (Small 9 Hole) Hole Spacing Inner Diameter Outer Diameter Top Speed Acceleration/Power Included With
44 Tooth 1″ 1.39″ 7 1/8″ Moderate+ Moderate- SkyHawk Angle Fire
50 Tooth 1″ 1.39″ 8 1/8″ Slow High Sold Separately