I need my head examined

I would like to know peoples' opinions/advice on the following mods I plan for my bike build: I now have a good 900 block Z1E 123141 with a decent 900 cylinder and what looks like a pretty decent head. Here is where the examination happens..........the plan is to bump the motor up and put it into a frame that will be modified (read - strengthened) with modern forks, bearings, swingarm, wheels tyres, brakes etc. Of course I have drooled with the best of them over Sanctuary's magnificent creations as well as many others and I am inspired by those bikes. I have a '75 frame with no title in decent shape apart from a deep saw cut going across half of a down tube near the headstock, I also have a titled '77 KZ 1000 frame which I would rather use and save the '75 for who knows what in the future. Will the '76 motor fit into the '77 frame? Any minor or major mods to look forward to there?

The next and most important question is about the motor. My options are; 1) keep it stock; 2) bore and re-sleeve the 900 block to 1075; 3) use a 1015 block and bore it to 1075 and drop that into the '76 motor; or 4) I also have a 1015 block that has been already bored and re-sleeved (diameter 73.3 mm.) making it an 1105 and stuff that into the '76 motor. Either option necessitates the purchase of a set of pistons as I don't have any serviceable ones. Will the 900 head that I have fit any/all of the options above?

All the stuff I have so far has come to me for free or very low cost and I know I have to spend money from now on, budget is limited but what I would like to end up with is a solid reliable bike that I will ride in all seasons. The plan is to get some Wiseco pistons for whichever option I choose, get the head ported /polished by Larry Cavanaugh, I will need some better cams and all the rest of the bits and pieces to keep it all together nicely like new cam chain and parts, springs etc. etc. bigger carbs and all that that entails. Body work and paint will be done by myself and I have some of the modern running gear already. I have a bunch of parts that I have ended up with that I will catalog and trade for some of the stuff I don't have when I get to the build proper.

Many thanks in advance,

Bluezbike

Frame/motor mounting points are same for 73-80 900/1000

I would go with option four(big boy package). Are your planning on beefing up the bottom end?

Yes, the 900 head will work on any of the proposed options.

Cylinder related....Get the 900 bored to 1015cc. 1105 leaves a thin sleeve for a street bike.

LarryC wrote: Yes, the 900 head will work on any of the proposed options.

Cylinder related....Get the 900 bored to 1015cc. 1105 leaves a thin sleeve for a street bike.

I did a 1045 on my first one and had no problems with it, given the increased summer temps these day and oil cooler would be advisable

Bore your 1015 block to 1075 or better. With headwork and good streetcams/carbs you will be happy. Huge difference from stock.
Wayne

Wireman, thank you for the frame info, that clears up a big issue, I will go with the kz 1000 frame.
Tomolu, if I went with the big boy package, what bottom end beef-ups should I be looking at, besides maybe welding the crank and beefing up the clutch basket?
Larry, I think I will call you one of these days again (we discussed a suzuki head a few weeks ago) for your best advice on engine size/cam choice/carb choice so everything works well as a unit to go with some head work by yourself if that's OK.
Johnnybravo, I like the idea of an oil cooler, thanks, maybe even a dry block treatment with top end oiling too.
Kzz1king, thanks, I am leaning towards a bigger than stock motor and....I like being happy

Thanks to all,

Bluezbike