HP estimate 1015 kit

What would be an accurate HP estimate for a 900 engine with a standard wiseco 1015 kit (10:25:1) APE 410 cams, stock unported head with 29mm smoothbores and V&H header?

I would guess around 85-90.

On a brake dyno, you will get about 70-75 hp IF your engine is properly tuned.

Where do you get the largest increases in power on these motors? Im trying to collect information to build a motor that'll crank about 120 or so HP. Parts are expensive and i'd hate to waste alot of money on trial and error. I assume that with a 1015 kit and the 410 cams that the really big power increases come from ported cylinder head and larger carbs?

Madkaw,read My sig and You'll see what I've done to My engine...and with what others have said,I'm guessing that I'm sitting around the 120 mark,as far as ponies go,Bud.
A night and day difference for sure!
That thing pulls so nice above 7 grand,and the midrange is great too!

Sandy, I trust with the long winter up there, you will have time to get the bike on a dyno and shed some real light on this subject. I have seen several KZ1000s get dyno'd (good running stock bikes) and their owners were always shocked to be in the low to mid 60s HP. I may be wrong but I think 120 is very optimistic for any streetable KZ but I guess it depends on the definition of streetable. I am guessing that you mid-compression, street cam bike does run a bunch better than a stocker. Get her dyno'd and let us know.

madkawltd900 wrote:

What would be an accurate HP estimate for a 900 engine with a standard wiseco 1015 kit (10:25:1) APE 410 cams, stock unported head with 29mm smoothbores and V&H header?

Like most things, the answer is, it depends. Are you going for maximum top end? Or are you going for a fatter mid-range? The kz1000 makes about 85 at the crank at about 9000rpm. if you degree your cams, you can get a few more ponies along the rev range. Jetting your carbs can bring more top end or more mid range at the expense of top end. I dunno about the cams, if they are for street/strip & road race I'd guess more mid range than top end, but the APE folks would know better.

I realize that this is old news, but...lots of top end makes for a peaky motor that will win a drag race, but a fat, smooth torque curve makes for a bike that is a hoot to ride in the twisties.

My vote would be for anything that gives you more torque between 4000-7000 rpm, because when you're back road blasting thats where the tach needle will be. Do your mods, jet your carbs for mid range and enjoy one sweet ride.

hope this helps...Sam

Sam, How did you measure your horsepower at the crankshaft? Just curious. I know there are dynometers that can measure crank horsepower but have NEVER seen one.

wiredgeorge wrote:

Sam, How did you measure your horsepower at the crankshaft? Just curious. I know there are dynometers that can measure crank horsepower but have NEVER seen one.

I think I made a slip of the pen there.:pinch:

85 ponies is what I've seen listed in literature for kz1000. Most horsepower numbers quoted by manfacturer, at least in the 70's wasn't rear wheel power but measured at the crank or counter shaft. At least I think.:blush:

Sam

Most of the horsepower listings by a manufacturer are crank horsepower which is quite a bit higher than brake horsepower (rear wheel). I am not sure how they measure horsepower (what type dyno) but most of the claims seem to be a tad inflated. I believe my 79 KZ1000E1 is listed by Kaw at 93 HP which is about 20-30 horsepower more than this bike actually makes at the rear wheel. I don't put much stock in factory horsepower claims.

Here you go WG, this one is for V Twins but they also make them for inline motors.

wiredgeorge wrote:

Sandy, I trust with the long winter up there, you will have time to get the bike on a dyno and shed some real light on this subject. I have seen several KZ1000s get dyno'd (good running stock bikes) and their owners were always shocked to be in the low to mid 60s HP. I may be wrong but I think 120 is very optimistic for any streetable KZ but I guess it depends on the definition of streetable. I am guessing that you mid-compression, street cam bike does run a bunch better than a stocker. Get her dyno'd and let us know.

I wish I COULD get it dyno'd but there's nothing in the immediate area.
Donthekawguy says there's one in His area,so maybe next summer I can get it out that way and get it done.