# 06 YZ 450 Total Drive Ratio Calculations

I figured I'd Post it and let you all comment on it I think Im going to try the 14/50 combination next time out, I think it will make the bike a little easier to ride but then again who knows.

Stock Gear Total Drive

2006 YZ 450 Gear ratios Ratios Ratio

Primary-61/23 (2.652) 2.652

1st- 27/14 (1.929) 1.929 8.35

2nd- 23/15 (1.533) 1.533 7.95

3rd- 23/18 (1.278) 1.278 7.70

4th- 24/22 (1.091) 1.091 7.51

5th- 20/22 (0.952) 0.952 7.37

sprockets 13/49 rear. 3.769

Gear Total Drive

2006 YZ 450 Gear ratios Ratios Ratio

Primary-61/23 (2.652) 2.652

1st- 27/14 (1.929) 1.929 8.22

2nd- 23/15 (1.533) 1.533 7.83

3rd- 23/18 (1.278) 1.278 7.57

4th- 24/22 (1.091) 1.091 7.39

5th- 20/22 (0.952) 0.952 7.25

sprockets 14/51 rear. 3.643

Gear Total Drive

2006 YZ 450 Gear ratios Ratios Ratio

Primary-61/23 (2.652) 2.652

1st- 27/14 (1.929) 1.929 8.15

2nd- 23/15 (1.533) 1.533 7.76

3rd- 23/18 (1.278) 1.278 7.50

4th- 24/22 (1.091) 1.091 7.31

5th- 20/22 (0.952) 0.952 7.18

sprockets 14/50 rear. 3.571

Gear Total Drive

2005 Yz 450 Ratios Ratio

Primary-61/23 (2.652) 2.652

First 27/14 1.929 8.22

Second 25/16 1.563 7.86

Third 23/18 1.278 7.57

4th. 21/20 1.05 7.34

sprockets 14/51 rear. 3.643

I don't understand how the last set of numbers in each series was derived or what they signify?

For instance, to determine the overall ratio for a given gear, let's say 1st and 5th gears with 13/49 sprockets: (Primary)2.652 X (Secondary)3.769 X (1st gear)1.93 = 19.28 and 2.652 X 3.769 X (5th gear)0.909 = 8.06