Kz650 bore/what to do

So I took the top end out of the ol 80 Ltd and found a bore of 62.04.. pretty bad.
So I've been thinking of what to do.
Searching eBay for cylinders, etc.

I think my options are this:
I've got a 77 out back in the barn with an unknown cylinder bore (some guy gave me the bike for parts). I could pull it out, but I don't know if the cylinder will be the same. That bike only has 10k miles, but it's seized.

I read somewhere that the kz750 top end is bolt-on. Anyone confirm this? Maybe it's just the pistons with a rebore?

I could also get the weisco pistons and bore out my cylinder. How much will this effect my carbs?


Anyone been in this situation and have some wisdom?

There are a multitude of options open to you including boring your cylinders oversize, using a 750 top end, or purchasing a clean 650 cylinder. There are tons of threads here on these options or better yet, check out kz650.info for information. That's a great site with a DEEP archives filled with great projects. One caution: your 650 has a conventional type cam chain and the 750 used a link plate type cam chain. Most of the 750 cylinders can accommodate both type of chain guide but do some research before purchase to make sure you get the right type.

BTW, how did you measure the cylinder and determine that it's worn? Did you use a proper bore gauge?

Yeah, took it to a shop.. it's waay oversized. I ended up getting the wiseco k700 kit and boring to 64mm

You'll like the Wiseco's. 10.25/1. Carbs will need larger jets.
Steve

The 750's valves are like 1 or 2 mm bigger. You can swap the hyvo cam chainrings with the chainrings off the 650's and your down the road.