76 KZ900 battery vs Z1, early KZ1000 battery

My '76 KZ900 has a seemingly unressurectable battery (old flooded, non-sealed style). I would like to replace this with an AGM battery, for obvious reasons. I've noticed that the KZ900 takes a different battery than both the '73-'75 Z1 and the '77 KZ1000, all of which take the same battery. The only differences between the two are that the Z1/1000 battery is about 3/4" taller and has a few more amp-hours. Also I have not been able to find an AGM battery for the KZ900, whereas AGMs are readily available for the Z1/1000. Is there any reason I can't/shouldn't substitute the Z1/1000 battery into the KZ? I'd almost have to assume they fit since the frames between the three bikes are so similar, and I'd almost have to also assume that the motors are so similar between the 900's and 1000's that swapping between the two would make virtually no difference, other than one is available in AGM and the other is not.

Thanks guys!

You can always substitute a higher A-hr battery, assuming you can get it to go into the space available.

You want the battery to be about the same output as the charging system +/- a little bit. Since the charging systems on all those bikes were the same, right around 12A, if you can make the battery fit than use it.

Thanks, guys!

I think I'm gonna get the AGM battery and see what happens. The only thing that puzzles me is why Kawasaki would have used a different battery in the first place, and only on the 900, for one year. Maybe the '77 900 uses that oddball battery also, I can't remember because I've slept since reading the chart. I guess my biggest problem is that I'm so used to dealing with GM cars, where EVERYTHING interchanges and is made with basically the same parts, that when I run into something where they use two different parts for seemingly the same application, I assume there MUST be a reason.

If I swap this battery in and lose my eyebrows or something you guys will be the first to know! :laugh:

I had the same problem with my 77 kz 900. I wanted a sealed battery. The only thing i found different is the early battery is about half inch longer. I used nylon spacers found at the local hardware store and used longer bolts on the side bracket that holds the battery in. Worked great.

A taller than spec battery likely won't fit past the KZ900's frame into the oem battery location.

Even the spec size battery is a tight squeeze into oem KZ900 position.

KZ900 battery pushes in from the side. Doesn't drop in from above like the Z1 battery.

Good Fortune!

Patton wrote:

A taller than spec battery likely won't fit past the KZ900's frame into the oem battery location.

Even the spec size battery is a tight squeeze into oem KZ900 position.

KZ900 battery pushes in from the side. Doesn't drop in from above like the Z1 battery.

Good Fortune!

Hmm...I accidentally got one that was spec'd for the Z1 and not the Kz900 and was able to make fit. There was a metal strip, I'd have to look to remember where it goes, that was already broken on my bike and allowed me to bend it out of the way. It is tight, but the taller battery does fit. Sure makes connecting the leads more of a challenge, though.

WmsKaw wrote:

Thanks, guys!

I guess my biggest problem is that I'm so used to dealing with GM cars, where EVERYTHING interchanges and is made with basically the same parts,

Guess you don't work on many SSRs.

Thanks for the heads up... going AGM then. I don't get enough time to ride the bike as it is, and it's one less thing I gotta fool with once it's in.

TexasKZ wrote:

WmsKaw wrote:

Thanks, guys!

I guess my biggest problem is that I'm so used to dealing with GM cars, where EVERYTHING interchanges and is made with basically the same parts,

Guess you don't work on many SSRs.

Nope. Newest GM vehicle I have is a '99 truck. Mostly '70's and '80's Chevy stuff I'm used to working on. Only two different batteries for most all GM cars and one will bolt in place of the other.