'78 KZ1000 engine rebuild

Hi guys this is going to be the first bike motor I've rebuilt and would like some input. I tore the head off today to send to Cavanaugh, ran the number on the piston after wire brushing the carbon off them to find out they're wiseco 10.25:1 1075cc. The number one looks to have some small nicks in the crown of it but all the others look fine. The P.O. did not silicone the o-ring groove around the cam chain tunnel when he put the 1075 in it so I don't think the head gasket ever sealed right found carbon on the gasket surface when it was removed. I'm going to split the cases and replace the bearings and o rings and the cam chain. possibly put in a back cut tranny and weld the crank. re ring the pistons and possibly replace the number one if I need to. have Cavanaugh do their stage one port job with new cams and then put it back together and see what happens. any suggestions from you guys are welcome and appreciated. also going to be running RS 34's on it with pods. Any guesses on power numbers or torque? ideas for gearing on a daily rider?

G'day,
LarryC does nice head work so you got hat part covered, he just did mine and i am following similar to what you are thinking. Larry supplied CamMotion Z1 Cams at a very reasonable price along with his head work and valve springs. I am going 1075, Larry's recommended 29 Keihin smoothbores (new),I have undercut (backcut?)ALL gears both acell and decel sides, FULL bearing and seal replacement etc etc. Gearing on the stock motor 15/35 gave me around 4000 revs at 60mph, i am going a little taller with the bigger engine but will return to low gearing once is run in sufficiently. I have been right through the chassis with Koni shocks,racetech springs and gold valves up front, new fork tubes from Z1 Enterprises (Jeff & Bakes rock!)tapered steer head bearings,roller swingarm bearings, new brakes,new this that and the other! Handles a lot nicer than you would think and went reasonably with stock motor (pipe,pods and rejet only), well enough to frighten a few 30 year younger riders on 30 year younger bikes!

YOu cant go wrong with advice from all these guys on hear, champion people all round & LarryC and the Z1Ent guys are just superb and helping with keeping these beautiful beasties alive and ROCKING!

Cheers from the land of Oz,
Kt.

I use www.gearingcommander.com when changing gear ratio's(new sprockets and chain).

well it;s started. I ordered all the gaskets and seals for the engine today {wanna talk about salty} and also ordered the new steering head bearings, front and rear wheel bearings, going to drop the bodywork off at my painters house in a few minutes, sending the head off to LarryC tomorrow if the UPS store is open, monday at the latest, ordered the new Kerker with comp. baffle, still waiting on the carbs from Sudco{bunch of slow sob's}, taking the bottom half of the motor to the blasters on monday to drop it off. I hope I'm not trying to tackle to much at once on this since it's my first rebuild but I want to be able to ride this thing when the snow melts. Wish me luck...:woohoo:

sounds like christmas came early, damn i jealous, :lol: post some pics so we can see the progress!

Well, my head got to Larry today and hopefully it will bear the one ray of light in this motor rebuild. I hoped it was going to be so simple as to split the cases verify everything was good put new seals in and be good, but no such luck. I think I'm making a roadtrip to Pearson Racing in Dayton to drop my crank off to be on the safe side. The counter weights have rust on them and I kinda have the feeling that even if I cleaned that all off and got it looking good that my bearings will be damaged. The cases also show signs of the crank walking so I may need to have the thrust bearing replaced. For $480+ parts it may be the best bet, I just don't want to get it back together and then have the crank come apart with the new found power Larry's going to give it.

well I took the day off work and drove my sorry butt to Dayton to drop the crank off at Pearson's to have it completely rebuilt. The good news is he said it wasn't in bad shape. he showed me a couple that he was getting ready to ship and from the looks of them that dude does some fantastic work. I'm starting to get excited;)

pearson does awesome work i haven't heard anything bad about him. you made a good choice.

update?

I've got the bottom end back together and should have the top end back on it this week. I'm taking it to Tom Sudman so he can show me how to degree the cams this coming weekend and should have it back in the bike by this Sunday. I have to get the caliper rebuild kits and the Tarozzi rearsets and we be ridin'.