'74-'77 KZ400 Twins with All-Metal Slides KeiHin Carbs
This is the first generation of the KZ400 twin KeiHin carbs that use a all-metal slide similar to the early XS500, TX500 Yamaha's. They are very diverse and have a lot of chances to make mistakes. You have to take great care in identifying the carb before any parts are attained. All the years listed will interchange physically so it is common to see the wrong set installed. Although I always recommend installing the proper set, as long as you match the parts to the ID on the set you are typically fine.
Below is a set of '76 KZ400D3 KeiHin 757B carbs. Notice the flat bottoms on the slides which is specific to the '76-'77 years only. Just one of the many pitfalls to this type of carb set found on '74-'76 KZ400's. Note that these models at times were produced as made in the US or made in Japan and imported to the US. These models have many differences in pressed in parts, non-removable float seats on some, and internal tuning. This makes this carb VERY hard to correctly rebuild without mistakes. This includes replicating mistakes made years ago before the current rebuild.
'74 KZ400D1(746A)(746B)(746C)
'75 KZ400D2 (746D)(746E)
'75 KZ400S1 (746E)
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'76 KZ400D3
'76 KZ400S2 (757A)(757B)(757C)(757D)(V5A)(V5B)
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'77 KZ400A1 (757B)(757C)(757D)(V5A)(V5B)
