Paladin. wrote on 05/29/08 at 03:56:26:For a given displacement, the single puts out more torque than a multi.
Right, this is about every single or twin 650cc bike I can find to compare. I ddn’t include the Suzuki SV 650 because this is quite sporty and high revving and no really the same category of bike as we should compare with.
But, very clearly, the average torque of the twins is higher than that of the singles.
Year Make Model Layout Style Hp at rpm ftlb at rpm
1996 Suzuki Savage 650 single Cruiser 30 5400 33 3400
1999 Kawasaki KLR650 single Dirt/Trail 43 7000 35 5000
2001 Sachs Roadser 650 single Naked/retro 50 6700 41 6200
2000 Aprilia Pegaso single Dirt/Trail 50 40
650 single average 43.3hp 37.3ftlb 1973 Triumph Bonneville 650 vertical twin Classic 49 7200
1975 Yamaha XS650 vertical twin Classic 51 7500 37 6000
1996 BMW F650 flat twin Tourer 50 6800 44 5500
1989 Honda XRV650 parallel twin Dirt/Trail 57 8000 44 6000
2001 Kawasaki W650 parallel twin Retro 50 7000 42 5600
2006 Yamaha Dragstar 650 v twin Cruiser 39 6500 37 5100
650 twin average 49.3hp 40.8ftlb 1999 Suzuki SV650 v twin Sports Tourer 69 9000 45 7400
If we exclude the Savage from the single averages (after all, it is deliberately restricted), the figures for singles rise to 48hp and 39ftlb average – close to the twins, but still below on torque as well as power..
If I were to add the following bikes’ details:
Year Make Model Layout Style Hp at rpm ftlb at rpm
1988 Honda XR600 single Dirt/Trail 45 6500 38 5500
1992 Yamaha XT600 single Dirt/Trail 45 6500 36 5500
And factor them up by 8.3% to equate their 600cc outputs to those at 650cc, and add them to the 650 single average, the average figures remain 48hp/39ftlb for the singles – still below the twins.
Maybe I’m missing something here, but I’m not quite seeing how singles give out more torque than multis.
If we look at 4 cylinder motors,
Year Make Model Layout Style Hp at rpm ftlb at rpm
1981 Honda CB650 Custom 4 cylinder Custom/Cruiser 63 9000 38 800
1977 Kawasaki Z650 4 cylinder Naked/sports 64 8500 42 7000
2005 Suzuki GSF650 4 cylinder Naked/sports 78 10000 44 7800
2007 Suzuki GSX650 4 cylinder Sports 86 46
2005 Triumph Daytona 650 5 cylinder Sports 114 12500 50 11500
650 four average 81hp 44ftlbNo – I still don’t see it!!