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HELLLOOOOOO everyone, this will be my first post here so please be nice to me

A man I have been doing some yard work for locally saw me riding my xr250l, and asked if I liked motorcycles, I told him I loved motorcycles. He told me that he had bought a 1980 kz1000 shaft brand new, he then had a laundry list of work done to the engine, such as a wiseco 1261 big block with 10.5:1 compression, welded crank, 33mm smoothbores, heads ported and polished, then had the transmission strengthened, a heavy duty clutch pack, and springs installed, andrews x8 cams, 4-1 headers, kerker muffler, and stiffer springs. He told me he had it dynoed at 167 hp, and 121 tq back in the early 90's when he did all of these modifications.

Now I know that a stock kz1000 makes about 90hp stock or so, so even with all of these mods those numbers seem high to me, but I am an expert in other manufacturers, and engines not these ol' oz's so what do all of you fine folk think, do these numbers sound right?

He offered to sell the bike to me for 2,000 since he is in his 80's, and says he is too old to ride so he wants it to go to someone who will ride it.

Sounds like a bargain to me whatever it's state. If your handy with wrenches go for it

$2000 is stealing a bike like that....

About that 167 HP 121 ft-lbs. claim - maybe possible, as the engine modifications he / you give could produce those numbers measured at the crankshaft. Also keep in mind that different dynos, even different dyno operators, can measure significantly different performance from the same engine.

If it still has a pre '81 cylinder head and making that kind of power on 1261 cc and 10.5:1 C.R., that head has to be ported / big valve / big cam within an inch of it's life.....I have specs for the Andrews 8X, and at 0.410" lift and 266 deg. duration, I don't see that much RWHP, more like 135-140...which is still pretty damn impressive, and way easy worth $2K

I will ask him if it still has the 2 valve heads or not, he put 20k miles on it in stock form, and all of the performance thing were done in 1993 with paperwork to prove it. He put 2.5K miles in 23 years, so the motor has barely any miles on it, and when he let me hear it, I didn't hear any tapping, knocking, or weird rattles. With that 4-1, and the kerker silencer it sounds amazing, has a very dopey idle, but doesn't stumble, and after hearing him rev it to around 6k it has a great intake snarl, and an amazing raspynesss to the exhaust.


I have ridden several kz1000p's, but never ridden a shaft before, are there any major differences in ride quality? Also do you think that the ring gears, and the shaft can handle that kind of power for long?

If I do buy the bike I will use it primarily for a commuter, and it is completely original. The original seat looks amazing, the original paint is very crisp, the brake pads are even still in amazing shape. Part of me wants to go completely custom, and build it into a monoshick cafe bike, maybe do a nice authentic style with the tail, and add a front headlamp like the original cafe racers had. But the other part of me wants to keep it completely original.

I don't agree with the "café" and "bobber" craze (fad?) going on currently myself. Most I've seen are products of back yard butchers that make good bikes into sketchy junk piles. The stock ST is a good looking bike...I would keep it as is if it is in good shape - if it ain't broke, don't fix it....

I will guarantee you that bike has a two valve head - no 4 valve head was ever available for any air - cooled KZ engine - EVER! Kawasaki's first production four valve head was the liquid cooled GPz900R (ZX900A1?) Ninja of 1984.

'81 and up heads are similar (2V) to the older Z1 style heads, but the '81 "J" model and later "GPz Bathtub" heads have bigger valves and ports, and both can be retro-fitted to a pre '81 KZ1000 engine for a serious performance increase.

The shaft drive will be o.k. on a bike like that if you don't hammer on the throttle to often. I would change the gear lube often and keep an eye / ear out for noise and metallic particles in the lube. The gears will inevitably wear out more quickly with the increased power, so you might consider converting the bike to chain drive at some point if problems do arise. That won't be easy, requiring cutting / welding and a lot of parts swapping, but finding good shaft parts might prove to be difficult in the future. You could put a wider rear wheel and tire on it at the same time....

I mis-spoke, I did not mean to imply that they ever made 4 valve heads, I left out "early" what I meant to type was "Early 2 valve". He told me after the engine was built, and it had been broken in he managed a 11.87 at our local 1/4 mile drag strip which seems very slow for having as much power as it does, maybe he was jus being cautious, but he showed me the time slip, and said he couldn't control it as it kept trying to loft the front wheel.

11.87 is slow for any 1261 cc KZ. Maybe he was having a bad day, or just sucks at drag racing....

My buddy was having a hell of a time with his 100 RWHP, 12 second KZ-LTD lifting the front wheel all the way into third gear. He is about 200 lbs, and even with the front end strapped down to compress the fork, he still couldn't use full throttle in the lower gears without fear of flipping the bike backwards. His best that day was 12.09 @ 111 mph (we made a lot of passes that day).

I should add - if that bike is making 140 RWHP, skinny tire, with an average rider weighing in at 170 lbs, it should be good for about 11.4 @ 122 mph. at elev. 1000' above sea level, temp. in the high 70's / low 80's.

Shafties are not as reliable as chains for obvious reasons but they hardly ever malfunction if well maintained. Plus no stretch or sprocket replacements. If you intend to pop wheelies all over the place the front and rear box will fail but it should go on forever with mod to hard use

Buy it and enjoy it as is
Dont drag race it and always put the power down from a roll and the shaft should last a long time as is.
With 23 years since the last rebuild the rubber bits may be hardened up and you might have a few leaks plus brittle valve guide seals but that would not stop me from buying and enjoying the bike.
I featured a Shaft bike here as a Bike of the Month and Dave loves his bike Shaft and All

Dave

Mrsuperbuckets wrote: He offered to sell the bike to me for 2,000 since he is in his 80's, and says he is too old to ride so he wants it to go to someone who will ride it.

Welcome aboard!

If you don't want to buy it, let me know.