What year motor is this?

Is this a 78 or 79?

The 1977 kz1000 serial number range is KZTOOAE000101 - 41170.

www.zedder.com/Info/77%20KZ1000-A1.htm

But someone installed a clutch and chain cover from a 79/80 mk2.

Wait, I read the number as KZT00AE-07593 but that's missing a digit. Can you type out what you read?

Is there a number after the 3 that is not visible in the picture? Engine # should be KZT00AE followed by 6 numbers starting with 0. For 1978 the range is listed as 040605-081565 including Japan and U.S. production.

Mike

DOHC wrote: Wait, I read the number as KZT00AE-07593 but that's missing a digit. Can you type out what you read?

Its out in the garage, I will check and get back to you.

DOHC is correct on the 77 KZ's. Mine is a 77 KZ1000 A, engine # KZT00AE000295.

KZT00AE079530

The zero on the end is very faint.

1977 range is KZT00AE 000001-043500 (Japan) 004018-040604 (U.S.)

Mike

Injected wrote: KZT00AE079530

The zero on the end is very faint.

Looks like 1978 range.

Mike

It might be an early 79 mk2 engine. But the head, generator, and points cover look like a 78. Any chance it's from Canada?

'79 KZ1000-A3 MKII (Canada)
Engine No. Range KZTOOAE075474 - 081568

www.zedder.com/Info/79%20KZ1000-A3%20MKII.htm

DOHC wrote: It might be an early 79 mk2 engine. But the head, generator, and points cover look like a 78. Any chance it's from Canada?

'79 KZ1000-A3 MKII (Canada)
Engine No. Range KZTOOAE075474 - 081568

www.zedder.com/Info/79%20KZ1000-A3%20MKII.htm

Its not a MK case - no extra rib on top case and it has a small center gear crank.

I am in Canada so yes its very probable its from a Canadian model bike, our bikes were usually ordered and received from Japan.

I thought it may be from a 78 Police model.

It does have a mix of parts on it, I think it has a earlier head, and it has a 903 barrel on it but the pistons are 70mm.

I see things that suggest it's a Z1 lower case, cylinders and valve cover. I can't read the embossment on the lower right corner but there is no brace above the stamp, which tells me it's a Z1 cylinder set. If you look at the lower right corner of the bottom case you see only one case bolt. Later cases (from roughly mid 1974 onwards) had two. The valve cover has rounded ends. This was the Z1 style. From '77 onwards they had a rounded end but with a distinctive semi-circle on the end.

The engine has a single brace behind the serial stamping, which means it's not a MK2. But it has a Z1A serial number and also has the oil capacity scribed on a plate, so it's not a Z1 upper case.

Overall, to me it looks like a replacement upper case on a Z1 engine.

I'm in Canada too. (Near Kamloops) Where are you located?