80's KZ Liter Bike input?

[Hoosier Daddy]

OK, I am sure to jinx myself by showing my hand before it is even delt... but I have been working on a future project and am about to change directions and need input. As some may know Drewski bought an H2 engine that was housed in a drag bike chassis. He and I have been P.M.ing on me buying the roller drag bike after he pulls the lump. My original intent was to go for a Suzuki GS1100 powerplant, but after much research those early 4 valver 1100's are getting rare and snatched up for pretty big money. Soooo I changed to looking for a oil cooled GSF1200 out of an early Bandit with more power, and seemed easier available. Still over a grand for an engine alone and >$2500 for a donor bike. : Like all good members looking for a project, I have been watching Craigslist for a "Cheap" donor.
This morning I found an 82 KZ1000P or KZP... that right, a Cop Bike! Decked out in all its tupperware with 32K miles and a runner that I could afford and local. Noow I know the early KZ900 was THE drag bike in the '70s and still used today on Old Skool bikes at the strip.... and later it was bored out to 1000cc. A guy I know has a couple of their standard liter bikes from back then, he refers to them as "J"s and says even though they are the same cc's they aren't a desireable as the earlier Z1's and it's later siblings and cheaper to pick-up.
Wiki says about the KZP...

"The engine was updated in 1981 from the Z1 type with a displacement of 1015 cc to the "J model" type with a displacement of 998 cc"

...so why are they not a desireable? Were the KZ's victoms of the '80s detuning like a lot of other vehicles? Seems with some quick research that as far as "Go Fast" parts availability, APE and Z-1 both list this generation in their parts line up.

So what gives? Why are these later J models, and persumably viewed as stepchild and not as performance oriented? Or is is a myth and they were the natural progression in performance capability that comes with model years?
Thanks!

 

[Nebr_Rex]

The "81 and up KZ1000 was 998cc via a smaller bore, but with the better flowing head.
The "80 and earlier was 1015cc back to "77 then it was a smaller 66mm bore for the 903cc/KZ900.
The economy took a dump and fewer "81 and up ( j models ) were sold/built. Thou they handled
and performed better stock. Lots of drag racers would swap the 'j' head onto the KZ engine.
The cop bike from "82 to 2002 was basically the same engine as the "81 and up 'j'. Lots of
performance parts are available and that doesn't include the GPz stuff. Check out KZRider.com
for more info. A guy on eBay called oinkjohnson is always selling old KZ drag bike stuff.


Edit: and hardley ableson cried to the government to have a tarriff on all imported bikes over 700cc
back in about "83.
.

 

[Drewski]

I'm no expert on the "J" by any means, but I'd buy one if the price was right. It just happens that I started with the older late 70's 1015cc version kz1000, so that's what I've stuck with. 8)

For an "all-out" drag motor, I'd guess you're probably better off with the meatier "1015" as a foundation.

As has been suggested, check the kzrider forum. Lots of advice and stuff for sale. 8)