Front Fork Swap / Upgrade?

I’m looking to upgrade the front end of my 1980 Z500B, does anyone know what diameter the front forks are?
Would it be sensible/advisable to mill out the yokes to accept a slightly larger diameter fork (2-3mm bigger at most)?
Ideally I’d love to go down the USD fork route but this seems like a lot of work and most USD set ups seem to be very wide between the forks?

What bikes have other people fitted forks off?

First off you need to measure your forks!!

Secondly, both the 650 and the 1000 have 36mm forks. If yours are smaller perhaps this would be a decent upgrande especially if you went with progressive springs as well.

If you want upside down forks then chances are you will need to convert your rear end as well if you want matching wheels and modern rubber. I have converted my kz1000 forks to zx7r upside down ones. It was a fairly easy and straight forward conversion. Infact i would call it easy. The rear was quite a differnt story.

galaxian wrote:

If you want upside down forks then chances are you will need to convert your rear end as well if you want matching wheels and modern rubber.

Galaxian, can you please expound on this a bit? Why would you need to make a change to the rear end after converting to inverted forks? Is it an issue of switching to radial tires?

If you fit an USD fork from a modern bike the front tire will be a 120/70/17 or 120/80/17 give or take and your old rear tire will be a 130/80/18 at best. This does not make for a good handling combination. Not to mention it wont look good with a modern front wheel and a stock rear wheel.