Did a small study:
, on Flickr
Gear Ratios F800GS: 42 rear and 16 front. Gives me ratio of 2.625
Wishing my bike to be more snappy. Aiming for ratio 2.75
Bad combo: 47R/17F R=2.764. Need to change chain as well, 116 links will not be suffice
Note that only 41/42/43/47 are common. 44 is rare and costs $127
Found that 41R/15F will give me 2.7
3, close enough to 2.75
44R/16F is exactly 2.75 but $127 ...
41R/15F will cost me cheap $43+$34 = $77
Ordered 41R/15F and will see how it goes...