TOPIC:

I’ve done a lazy google search to see if an airbox from 83 kz750-4 will work on my 78 kz650 and motmfinding much.
I’m assuming the carb boots are different but does anyone Here know if boxes are same?

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Ok thank you. Looks like the same box as I saw as well. No interchange info there. The cap indicates they used the same cap across the line.
Now, can anyone verify that box is the same before I waste more money

Looks like bike bandit shows different part numbers between the 650 and 750.

Until you get a definitive answer, you'll just have to do a visual comparison.
A couple of thing to note is the shape of the body & also where the mounting brackets fit.
The 70s 650 airbox duct holes are different than the 750-4 airboxes.

The 81-83 KZ650-CSR models use the same airbox as the KZ750E/H models, but some of the other 750-4 airboxes are different, especially the shaft drive models and 750-L3 & 700-A1 chain drive.

The 81 650-CSR had VM24 carburetors, and the airbox ducts are unique to the model & NLA; the earlier ducts won't work with that airbox. The ducts for the BS carbs are still available and were used on all of the 750-4 models & 82-83 650-CSR, but those ducts aren't a direct fit for VM24 carbs.
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