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The workshop manual for my 220 states that the maximum horsepower for this bike is 27kw ( 37 hp )
I recently had my bike dyno`d & the reading came out at 25.1hp @ 8146 rpm,with 16.2ft lbs, this was taken from the crankshaft...at the wheel it read 22.8 hp 8146 rpm 14.8 ft lbs...this reading was with my bike suffering from worn crank bearings....
I had the motor stripped & fully rebuilt with all new genuine Kawasaki parts, I never replaced the piston as this was new only last year & has done very little use, the bore was excellent too & didn't require a replate, while it was apart I had the inlet & exhaust ports measured & professionally opened up & polished inc all the transfer ports etc, the head was also milled down, re-profiled & squish set, the piston was also modified to suit the inlet side. The jetting was dialled in on the dyno & the new reading was as follows...39.1 @ 9370rpm with 24.6 ft lbs (crank ) 35.9 bhp @ 9370 with 22.8 ft lbs.
So even after a full rebuild & tune my bike still doesn't perform like the manual says it should, was Kawasaki exaggerating the performance of these bikes?? I will say that even before the rebuild & tune my bike went very well & hard to believe with just 25 hp!....now its a real rocket ship with loads of power everywhere & I would say will give a 250 a good run for its money.

That's interesting. I've seen a few dyno charts for the h series that usually put em at 28 rear wheel hp, so you're spot on.

There was nothing mentioned about the 200s bhp in the manual ? ( the 220 manual is a supplement which came with my original kawasaki factory workshop manual ) ..my 220 has a full fmf pipe with powercore silencer, 35mm kdx 200 carb jetted to suit on 40.1 mix with snorkel removed & modified airbox lid, also running the boyesen rad valve with dual stage reeds...like I mentioned before my bike ran very well with this set up before I had the motor rebuilt & tuned, I find it difficult to believe that kawasaki quoted 37 hp for this bike in stock form after reading my final dyno print out...perhaps another manual error which should read 27 bhp & not 27 kw ??

Every dyno is different. Back in the day, the dirt rider magazine dyno always have results that were lower than others. For example honda would claim 60 rear wheel hp for a cr500, the dr dyno would read 50 rear wheel. I'd say that on a dyno where a 125 makes 35 hp, the kdx 200 would be at 30, and the kdx200 would be 25hp, with 14ft lbs of torque as an example.

cornishwrecker220 wrote:The workshop manual for my 220 states that the maximum horsepower for this bike is 27kw ( 37 hp )
I recently had my bike dyno`d & the reading came out at 25.1hp @ 8146 rpm,with 16.2ft lbs, this was taken from the crankshaft...at the wheel it read 22.8 hp 8146 rpm 14.8 ft lbs...this reading was with my bike suffering from worn crank bearings....
I had the motor stripped & fully rebuilt with all new genuine Kawasaki parts, I never replaced the piston as this was new only last year & has done very little use, the bore was excellent too & didn't require a replate, while it was apart I had the inlet & exhaust ports measured & professionally opened up & polished inc all the transfer ports etc, the head was also milled down, re-profiled & squish set, the piston was also modified to suit the inlet side. The jetting was dialled in on the dyno & the new reading was as follows...39.1 @ 9370rpm with 24.6 ft lbs (crank ) 35.9 bhp @ 9370 with 22.8 ft lbs.
So even after a full rebuild & tune my bike still doesn't perform like the manual says it should, was Kawasaki exaggerating the performance of these bikes?? I will say that even before the rebuild & tune my bike went very well & hard to believe with just 25 hp!....now its a real rocket ship with loads of power everywhere & I would say will give a 250 a good run for its money.

After these mods , how was the wonderful bottom end that the 220 is known for ? Or did it turn out to be a MX power band like most 250's ? Incredible power gains one way or the other !

I think Kawasaki just plucked that figure from fresh air! as no stock bike will make close to that!
good results from your work though Alan
best regards
john

The bottom end is still there....just more everywhere!! it really is like a different bike especially higher up the rev range...I will be finally fitting your old kx front forks in the next month or so john !!
Will send you the pics when she`s done bud.

cornishwrecker220 wrote:The bottom end is still there....just more everywhere!! it really is like a different bike especially higher up the rev range...I will be finally fitting your old kx front forks in the next month or so john !!
Will send you the pics when she`s done bud.

look forward to the pics bud
best regards
john

The manuals err on the high side. Different dynos will give different readings.