How much hp does a 250cc motorcycle have?

Answer 1

Depends on-

1) if it's 2-stroke or 4-stroke

2) how many cylinders it has

3) when it was manufactured

3) how much it's tuned

For example, a 1992 Honda crm250 makes about 40bhp out of the factory. This is a single cylinder, 2-stroke enduro Motocross bike. They can be tuned up to near 50bhp though.

A late model Aprilia RS250 makes around 62bhp out of the factory. This is a twin cylinder 2-stroke sports bike.

The 250cc 2-stroke race bikes in 250GP make a little over 100bhp (gulp!), but these are in a very high state of tune and rebuilt every week.

4-stroke bikes make less peak power because they ignite the fuel mixture in any given cylinder once every four strokes, whereas 2-strokes ignite the fuel mixture once every two strokes (hence the names) however 4-strokes usually have a much wider power band and flatter power curve than the peakier and narrow power banded 2-strokes which tends to make them much easier to use.

Not sure of any figures of 250cc 4-strokes but would expect a single cylinder motor to be 25-30bhp for the more modern bikes. Newer, more advanced motors are of course usually more powerful than older technology, however 2-strokes are being fazed out and no longer developed because their emissions are not as clean as 4-strokes (much to many peoples sadness as 2-strokes are much more exhilarating to ride). I personally have a 1992 Honda crm250 (2-stroke) and a Triumph Daytona 675 (4-stroke) and though the Triumph has 3 times the power of the Honda, it's the CRM's "get you when your not looking" delivery that has the biggest grin factor!

I don't see how anyone could improve on this answer. He hit it pretty well.