The best-selling two-wheeler in Canada has been entirely redesigned and is now powered by a liquid-cooled and fuel-injected four-stroke.
Yamaha’s BW’s 50 scooter has topped motorcycle sales in Canada for many years, partly because it is affordable, partly because it appeals to young riders, and partly because it’s bulletproof.
The early release 2012 BW’s 50 replaces the aging air-cooled two-stroke engine with a modern 49 cc liquid-cooled, three-valve, four-stroke single that is fuel injected. The reasons behind the change are simple: the new bike will be more fuel efficient and it will burn cleaner. It also promises smoother, quieter operation.
Styling is very similar to the outgoing model, with its distinctive, bug-eyed twin headlamps and fat tires. A 23-litre storage compartment rests under the seat and the fuel tank holds 4.5 litres. And get this: at 93 kg (205 lb), wet weight is one kilo down on the two-stroke model.
Retail price is $3,079, a $170 reduction over the 2010 BW’s 50, the last BW’s listed on Yamaha Canada’s website.
Compared to 0.35kg-m(2.5 ft-lb) @ 6,000rpm on the old model.  Strange I would have expected a 2-stroke to be zippier.
We need a full-on CMG test here.
For comparison, a human being cranks out 0.1 hp and 0.5 in short bursts.
Max torque: 3 ft lbs (yamaha website)
As Patrick said…power differneces and what would the top speed be…some city streets are 70kph…
Later.
I want the 125Z!!
Would there be any significant power change going from a 50cc two-stroke to a 50cc four-stroke?