Katit's 1978 KZ650 project

Nessism wrote: www.enginehones.com/212240sc.html

Used cylinders & pistons are much cheaper than going the bore & new pistons route. Success depends on finding good used parts though of course.

Thank you! Order placed. Buying a ton in last couple days, now to wait for stuff to come in.

Now I need to work on prepping all parts for paint. Even though cerakote does not need to be baked- they recommend bake parts before to make sure any grease is burnt. Going to get used oven from CL for that. Later I may convert it into DIY bigger oven cabinet.

After engine cases clean and painted - I will start working on checking all parts per FSM

Started cleaning up this head. And dang.. Whats wrong with those people?
2 of the intake threads messed up in a bad way. No easy timesert here. Any suggestions on repair?

And.. What do I do with those emissions holes? I want to use my cover

And, speaking of those 750 heads. What else will I need if I find one? Do I need different carb? Will 650 cylinders work? Basically, if I shop (if) for 650/750 head, what else will I need?

At least with this one I know with repairs I have most parts

At this point I feel like I need to use machine shop for head work. Any recommendation on good one in US? I am in St Louis, don't know of any local shops but I am OK with shipping if they are good.

Man that sucks. You think they would have stopped after the first one. APE is a good resource but you will have to ship. They specialize in repairing damaged heads. but a used head might be a cheaper route.

Some people should not be allowed to own tools.

Emailed APE, will see how it goes. Checked eBay for used stuff - it's all lottery. they all $100 give or take and all "used in great condition". Mine was so dirty I didn't even see those studs until cleaned and blasted those spots. So, thinking how fragile those thread are - I can see how pretty much "any" 40 year old motor will have similar issue(s)

There is one NOS head on eBay for $800 haha.

Have you tried chasing the threads with a tap?  Just a guess but I think it would be M6 by 1.25.

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Have you tried chasing the threads with a tap?  Just a guess but I think it would be M6 by 1.25.

Look at pictures. Threads IS there. They just not in correct spot, about 3/16 off center, putting intake manifolds in a bind. Someone broke bolts but wasn't able to correctly extract broken bolts making it even worse.

I get it, it was PITA with head/engine on a bike, but...

If you pay the shipping you can get a 650 head for free. All threats in good condition, no broken fins. Only cam bearing cap #2 and 4 are missing.
It was a cheap 50 Euro ebay offer i bought only for the shim under buckets i need. Both cams also available.

 
 
 
 
 

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 Only cam bearing cap #2 and 4 are missing.

 

That "only" is a problem. They machine caps with head at a factory, you can't just replace cap as they go mated with a head. This is main reason I am not using my original head (see page 1) as someone replaced cap #8

And how do you know everything else is good? Valves, guides etc? If it was just for threads I could probably figure out something myself or fix it quickly locally. I am guessing surfacing might be needed and valve lapping and potentially guides.

Yesterday I put some more time working on head. Took valves out, inspected a little. There is corrosion on guides and valves. Not working surfaces but still.
Checked manual, removing/replacing guides if needed is not a problem , I got all the tools.

If I get Neway cutters - I can do valve seats no problem.

So, the only thing remaining - check for warpage and fix threads. Got helicoils on order, will try to repair. 

Sounds like with my own tooling I should be able to get most of it figured out.

Any pointers on exact Neway kit/set? I know I need 45/30/60 cutters. 

Any pointers / info on how to block smog ports? I see it's just a hole going to exhaust valve. How should it be plugged?

I blocked the emission holes by tapping them (from the valve cover side) and then screwing in a set screw with some red threadlocker.

If you have a good head that is missing a cam cap try pulling the valve train and bolting in a cam. try several different cam caps from the other head you have. If it turns over easily by hand I wouldn't hesitate to run it.