fork oil question

Still working on my '81 GPz1100. I have the front wheel off to have the disks turned and such, so it's an obvious time to check/change fork oil. My Clymer doesn't specify oil weight, though. 10 weight and 15 weight seem to be the most often used, and I would guess that 10w would provide less dampening than 15w. I won't be using this for hard sport riding, mostly using it as a sport/touring bike. What should I use?
While I'm asking questions about the forks, this bike has air fittings on each fork cap. In my younger days it was pretty easy to find a balance hose for these, but I don't seem to be able to locate one. Any suggestions?
Thanks.
Bruce

Bruce, if no one gets to you this afternoon, I have the shop manual for your bike, but it's at home...I'll post later, if necessary.

Bruce:

The manual specifies 10W20. As for the air fitting, I have seen them on eBay...so patience is in order...keep watching...all things appear on eBay, eventually.

10w20? I don't find fork oil being sold in a multi-viscosity form. I find SAE5, SAE10, SAE15, SAE20, etc. Does the manual mean that I should just use an oil with a viscosity between 10 and 20? Oh, yeah, and once I figured out what to look for, I found Progressive Suspension's Air Fork Balance Kit (AFB-1) sold all over the place, including Amazon.com! I've ordered one from CruiserCustomizing.com, 'cause theye were the cheapest.

Bruce...that is what the manual states...use 10 or 15W and you'll be correct.

Sorry to jump in on this thread, but I am confused here also. It says in my manual (79 KZ1000 MKII) to use 10W20 but all I can find is straight weight ie: sae5, sae10, etc... Is it OK to use straight weight when multi viscosity is called for? And which weight is equivelent?
Thanks