Hi Trolle,
I didn't know that the european bikes had different final drive ratios - are you certain that maybe there isn't a typographical error in the OEM catalogue information - it would only be a matter of one digit ?
Technically speaking, the ratio is supposed to be expressed as the number of teeth on the ring gear and the number of teeth on the driving gear , and not just the mathematically reduced ratio or simplified fraction.
If the European and USA spec-final drive ratios were indeed different during that time period, one possible explanation is that during this time, we had a national speed limit of 55 MPH, so operation at higher speeds was perhaps less common over here. However, I think that the sport of drag-racing originated over here in the U.S, so we've always had an emphasis on acceleration capability over true top speed. Hhaving a 32/9 (3.56) rear end instead of a 31/9 (3.44) would give slightly better acceleration from a standing start, assuming bikes/riders of equal weight and engine torque output. Now that the national speed limit is no longer fixed, nor at 55 mph, we are consuming more gas than ever before. I wonder if the folks in our congress have pondered the idea of re-instituting the 55 MPH speed limit to conserve fuel again ?
Note, I was not and am not a fan of a 55 MPH speed limit, but I suppose if things get as bad as they were in the 70's/early 80s with fuel costs we may see history repeat itself. Conservation is a much easier thing to do than implementing a global hydrogen fueling infrastructure, though not as sexy...
