VIN and Engine Numbers 1977 KZ1000

Hello all, thanks in advance for help on this topic. A guy has a '77 KZ1000 for sale. Frame KZT00A503840. Engine KZT00AE043616.
Looking on Zedders the frame checks out to be a '77 A1 but the engine falls in two ranges. Zedders says it is a '77 B1 LTD, but it is also shown in the range to be a '78 A2. Any thoughts on this? The bike has a rear disc brake but has LTD wheels and side covers, the owner thinks these were changed. Thanks again!

The bike is known by the frame S/N. It has an "A" in it, not a "B". Therefore it's a standard model. As for the engine...it could be original to the bike but an exception to the rule, or it could be a replacement. In any case it doesn't have anything to do with the bike designation.

But if the engine is not an A1 engine and it's a B1 out of a LTD, isn't value dramatically decreased? I wonder why the discrepancy on Zedders. The bike runs good but has the LTD pieces. He offered it at $2500. I'd buy the it but would like to know if the motor is original to the frame.

Z1 bikes had a close correlation between engine and frame numbers, but the difference could vary by up to 300 where the engine could be higher or lower. With Z1's I've heard of several frames with engine serial numbers up to 6,000 numbers different, but those were extreme exceptions. The important thing to take from that is that there were always exceptions back then, and we don't know why they occurred.

From 1976 on ward there was no correlation between the two component serial numbers. I don't know where Zedder got their info, but I've never known it to be incorrect, although that's a possibility. In my view the bike value would more or less the same regardless of the Zedder info. If the bike is in good shape and you want it then go negotiate a sale.

Oh...lots of people put LTD stuff on their bikes when the LTD line came out. My Z1B back then had LTD bars and seat. Many people bought the chrome headlight and gauge lowers.



I don't think the value would be