Another amateur build thread

My head s finished and will ship back to me tomorrow. Chris sent some pictures today and I thought I'd share them.

After cleaning the head, he flipped it over and the threads from one of the cam cap holes dropped out n his bench! That hole got a time sert. Also, he has gotten enough requests for stud and nut conversion for the cam caps that he has developed a kit. I got the first installed set. He also has stainless steel exhaust studs and nuts. The studs install with an Allen wrench! I am really looking forward to seeing it all in person.

Good to see things moving forward, head looks great. Are the exhaust nuts "self locking"? I am using the same type of studs but the nuts I have are copper plated locking nuts from the car world

That is a good question, that I failed to ask. I will take a look when it arrives.

By the way, if the cam clearancing looks a bit amateurish, that is because it was done by an amateur (me). Chris said that every head he has gotten in for a performance build was already clearanced, so he is not set up to do it. 

The exhaust flange nuts are serrated, so they should "lock."

I have a couple of questions---

1. The GpZ steering stem should work in the KZ frame, if I can find the proper bearings. Allballs does not list a kit, likely because of the upper bearing situation. 
The stock KZ bearings are 25 / 47 / 15 (top) and 28 / 52 / 16 (bottom). The stock GpZ bearings are 28 / 52 / 16 (top) and 30 / 55 / 17 (bottom).
Soooo, I reckon for the conversion I need 28 / 47 / 15 (top) and 30 / 55 / 16 (bottom). The Z1, KZ900 uses a 30 / 52 / 17 on bottom.
The top size seems impossible to find except from AliExpress, which I am reluctant to use. However, I found an upper bearing that is 28 / 47 / 12.
My question is, will the extra width on the bottom bearing and the less width on the top bearing be a problem?

2. What size do I need to drill the block oil passages to compensate for the larger APE studs?

Thanks

I don’t see the narrower top bearing being an issue (still located better than the ball type) with the bottom they don’t sit very deep so you may have to sacrifice the dust seal 
Alternatively you could reduce the stem to 28 and use the stock bottom bearing (which is what I have done)
with the oil passage, if I remember correctly you drill to the original size at the gasket face (the casting “tapers” to a smaller opening part way down) Zed1015 was the guy that posted this mod