Fuel Requirements for 1980 KZ1300?

After reading some postings concerning Fuel and it's relationship to compression I do have a question concerning my recently acquired 1980 KZ 1300 and it's fuel requirements. Leaded fuel was still available back then with higher octane ratings but I cannot find the fuel specs. for this bike and was wondering if anyone in KZrider knows what this bike feeds on? Normally the owners manual would list this requirement but it did not come with the KZ 1300.

My thoughts on this subject:

Since I already own a 1972 HD Sportster, the fuel reqirements are at least 92 octane leaded fuel. Any less of a rating and this machine does not run right. So I run 92 unleaded and use a lead additive to meet the requirements. Also I have a 1989 Honda VTR 250 Interceptor I restored 2 years ago and the fuel requirements are at least 90 octane unleaded. No problem there.
I might be on the wrong track, but I am thinking that the KZ 1300 would use at least 92 octane unleaded fuel with an lead additive to meet the reqirements.

Any thoughts?

87-89 pump gas should be fine with stock motor

I second Plummen...Kawasaki was ahead of the curve when they introduced the Z1 in 1972...it was designed to run on lower octane, lead-free petrol...which the engineers foresaw as the wave of the fueling future in NA and Europe (their intended market)...subsequent Kawasaki models followed suit.

We have several members with KZ1300's...one of whom is a moderator...he should be along shortly to answer your query...

Thanks guys. Somewhere in the 70s and 80s unleaded was becoming more of a requirement by the government than the engine manufacturers but somewhere along that timeline the switch between leaded and unleaded line was blurred. Well, at least for me during a CRS moment.

it has a bit to do with the efficiency of the combustion chamber. i would say that the 1300 has smaller pistons and therefore should be more likely to run well on lower octane fuel than something like a Harley.
Just try a bit of lower octane and listen for a knock in the mid range, under light load.
Good luck