BMW Twin Close Ratio Gearbox

For all our products see our full product list

The BMW engine does not have a primary reduction from the crankshaft to gearbox as is typical in most engine configurations.  This makes overall gearing a problem, particularly for small wheel sidecar outfits, with this in mind a 6.67% increase between the engine and gearbox has been incorporated. We now offer an alternative ratio more suited to solo's and larger wheeled outfits.

The standard gearbox ratio’s are unsuitable for serious racing and have been changed, as shown below. All gears have three undercut engagement dogs to allow for rapid and reliable changes and positive retention

Both shafts supplied fully assembled and ready to fit and Superfinished as standard

We can supply both the older and newer cam forms on the input drive gear, so please specify when ordering. (Photo can be supplied to illustrate the difference).



BMW Standard Ratios >
1st 4.401:1
} 35.0%
} 27.6%
} 19.3%
} 10.2%
2nd 2.860:1
3rd 2.071:1
4th 1.670:1
5th 1.500:1
 
Overall reduction 1st - 5th : 65.9%
Nova Sidecar Close Ratios >
1st 18 - 30 2.999:1
} 25.0%
} 20.0%
} 14.8%
} 8.7%
2nd 24 - 30 2.250:1
3rd 25 - 25 1.800:1
4th 27 - 23 1.533:1
5th 27 - 21 1.400:1
Input Drive Gear 15T
 
Overall reduction 1st - 5th : 53.3%
Nova Solo Close Ratios >
1st 18 - 30 3.214:1
} 25.0%
} 20.0%
} 14.8%
} 8.7%
2nd 24 - 30 2.411:1
3rd 25 - 25 1.929:1
4th 27 - 23 1.643:1
5th 27 - 21 1.500:1
Input Drive Gear 14T
 
Overall reduction 1st - 5th : 53.3%

BMW Twin Gearbox

Price £1700.00

+VAT (if applicable) & Carriage

Availability: Call

BMW Twin Vernier Cam Timing Sprocket

For all our products see our full product list

Direct replacement for the standard item.  Allows precise cam timing to be achieved.



BMW Twin Vernier Cam Timing Sprocket

Price £275.00

+VAT (if applicable) & Carriage

Availability: Call