need help with kz 1000 build

[gixxer]

I just bought a 79 kz 1000, and im looking to drag it. The motor it had in it was a shaft driven motor and im looking to put another motor in it. I wanna know what i should look for motor wize, and where to start with buying parts, thanks.

[SixShooter]

900 crank and cases with a J-model head and trans is the preferred combo IMO. You can get by with a 1000 motor up to mid-8s with billet trans shafts, billet basket, and studs top/bottom. J-model head will save you $$. Comes with bigger valves. Lotsa used parts out there. More so than Suz GS's. Tricky getting a wide tire to work in that frame without offsetting the rear tire. U gotta get creative.

[gixxer]

Does the year range matter alot for doing this or are they pretty close in bolt up, thanks for the help

[gazx10]

all depends on what your goal is, how fast u trying to go?

[selfmade]

We have alot of old kz parts an two complete motors call 4077224602

[SixShooter]

Most parts can transfer. You hafta bore 900/1000 cases to fit a j-model trans cuz the bearings are larger diameter. There's a bearing kit out there to drop it right in though. The other thing is the crank center pin has different counts between j-model and 900/1000. You hafta use j-model cam gears with a j-model crank, 900/1000 gears with a 900/1000 crank.

[gixxer]

thanks for all the info and help

[dragracer]

thanks for all the info and help

Send me a PM with your email address. I can help share with you what i did with my recent KZ build along with some pictures. If you intend to push button start a KZ, using the Mark 2 crank is highly advisable. While the 900 cranks are lighter and spin up faster, the main 2 drawbacks are they will break in the center unless you install a HD center. Secondary to that problem is you will have issues with it spinning off the starter gear on the end of the crank. You cannot tighten that small bolt with enough torque to keep the rotor on with a large, high compression motor- eventually it will fail. The Mark 2 crank is heavier but it has the HD center, it has the big end on the crank with a large bolt that you can torque down enough to keep the rotor from spinning. The other option is to use a j model or gpz crank and have the hivo center replaced with a 16tooth center from a Mark 2 crank. You must then use j model pistons and a shorter block. Unlike GS Zuks, big Kaw motors are harder to crank and will require a 24 volt starting system and a good starter. I use a starter from a DOHC Honda because it has more hp than the original Kaw starter. The other option is to send your Kaw starter to Paul Cashio and have him modify it into a higher torque setup- you will still have to 24 volt the starting system. To reduce resistance against the starter, you need to consider using an ignition controller that will retard the timing while the starter is cranking over the motor. The Pro Series 2 has this feature and works great. I think the Dyna 2000 does the same thing but do your research. Once you overcome these items, even a 1500cc Kaw motor will spin over very fast.

Your next challenge relates to chassis set up. Actually this is simpler than you might think. I would suggest using a mono shock arm so you can better tune the suspension with late model sport bike shock like the Busa shock. you can get them revalved to meet the specifications of the bike. I use a stock Busa shock on my KZ and it works very good so far. The arm came off a 93' water cooled GSXR but the oil cooled arms are about the same. Be sure to get the pivot also if you use this type arm. Install this arm on the chassis is not very complicated but requires some welding. Hopefully your chassis still has the brackets for the center stand. You will use the two inner most brackets to attach the pivot like. The next step is to position the bike in the exact ride height you want so you can figure out where to weld in the bracing for the top shock mount. On the water cooled arm, the shock will be at an angle towards the front of the bike and at the rear of the engine cradle. You will need to weld a piece of metal vertically across the rear of the engine cradle where to attahced the upper shock mount. Weld two pieces of angle iron at the same width as the shock mount, drill holes for the shock bolt and you are done!!! Be sure to gusset the angle iron on the vertical bracket and reinforce this area well since the weight of the bike/rider is being supported by this arrangement. Also gusset the center stand bracket where the pivot is attached. You don't want any of these area breaking loose. Oh, an arm from a 2000 up GSXR600 will work also but the shock stands up vertically at no angle. You must then fabricate a U shaped bracket welded to the seat rails to attach the shock. If some cases, you will not be able to retain the rear foot peg bracing because the arm will hit it due to the width.

I typed more info than i meant too. Sorry about the run on. Like i said, hit me up on a PM and i'll help you in anyway i can.

[dragracer]

I made an assumption in my post that you were not building a wheelie bar bike. If you are, i would use the 900 crank with an outboard starter.

[gazx10]

built dozens of these things in last 30 yrs.10-9-8 sec motors. u can overbuild or underbuild and waste money. it's all in choosing the right combination, but no one here can help or give accurate advice not knowing what u are trying to accomplish.