TOPIC:

2.15 is somewhat common for rear wheels, but most fronts are a size or two narrower.

Not sure if there is the info you are seeking there or not? Will say there is a great deal of info on the 400 and 440 machines located here  kz400.com/  

I do not think the site is being updated rather sort of kept as was/is but there are manuals parts lists how to's and lots of info there. If you have not looked at it before you might find it useful. 

I've seen that site, there is a lot of info there, but just like you said, it has not been updated in a while, and at this point it seems (at least to me) that most of the info form there has been extracted and poured in this forum in one way or another.
In regards to the subject at hand, no, I did not find which kz400 variant has the 2.15 spoked rear wheel on kz400.com

​​​​Thank you anyways for the help
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LuisLAN wrote:

Which year KZ400 had 2.15 spoked rear wheels? I've been reading here trying to find the answer, but all I came up with is that some have 2.15 wheels and some 1.85.
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I would like to swap the 1.85 I currently have for something wider, so far the easiest way seems to be a 2.15 from another kz400.

Maybe lace a 2.5 wheel on to the hub?

What is your experience with this mod?

The 2.15 is a KZ650 rim laced to a KZ400 hub.


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