4.28 to 1 Reduction Gearbox with a 78 mm clutch drum for 76 mm clutch rotors.
Fits the Honda GX35, Tanaka PF-4000, ZENOAH 41.5 cc & some others. Engine in NOT included.
This has a 14 tooth one piece heat treated gear and shaft with the 9/16-18 right hand threads. The larger 14 tooth gear makes this gear box very smooth and quiet.
We use a clutch drum has 9/16-18 right hand threads and may be zinc plated.
It has two high speed double sealed ball bearing that have a 1-3/8" OD with a 9/16" ID that hold the 14 tooth gear and the output shift is supported by two high speed double sealed ball bearings with a 1-3/8" OD with a 5/8" ID.
The output shaft is 5/8" OD with a 3/16" keyway and two snap ring groves.
To move forward the engine will be on the LEFT side. The gearbox is to the right of the enigne. Look at the Axle mount kits to see how we use this gearbox.
This gearbox reduces the output 4.28 to 1. Examaple: If your engine turned @ 7,000 rpm's with this gearbox you final output rpm would be 1,635.5 rpm. This make it a lot easier to get you final reduction on lots of small projects. Your sprockets can be 4.28 times smaller on the wheel or axle the drives the unit and the sprocket on the gearbox shaft can be a 9 tooth or larger depending on the size of chain and sprockets you need to use. This also allows you to use Freewheel sprockets so you can coast with zero drag.