CB350 and CL350 Twin '68-'73 KeiHin 28mm CV's

These carbs come in four different versions with four different ID's and can be found on CB and CL 350 Twins made '68-'73. I will refer to them in two generations for simplicity. First gen with a large square-ish brass float and larger float bowl and the second gen with the smaller bowl and the round bob brass floats. However, the engines can accept all variations. 3D and 722A are the most common for our rebuilds. I also can use fiber or stock style brass floats in my rebuilds due to the fact that brass are just not as dependable and fragile in my opinion. Each model is tuned a little different and they can easily have other years miex parts and there are some truly terrible kits out there that could have been installed. This does not cover the SL350 twins, I rarely rebuild that model of 350 twin carb. Keep in mind there are other differences between these types like bowl drain screws, but since bowls can be interchanged on second gen, I feel the air screw is the best guide.

'68 CB/CL350K0-------------------------------------------------350A (First Gen carb)
'69 CB/CL350K1------------------------------------------------ 3C (First Gen carb)
'70-'71 CB/CL350K2-K3---------------------------------------3D (second gen with small exposed air Screw)
'72 CB/CL350K4-------------------------------------------------3D (Second gen with hooded small air screw)
'73 CB/CL350K5-------------------------------------------------722A (Second gen with hooded larger air screw that uses washer and o-ring)

The list above is more useful for the evolution of the carbs rather than implicitly corresponding years with styles. Honda had some versions run later and others started sooner. So use the list as a loose guide to get a good idea of what you should have on your year. Not to mention, they all interchange so you could buy a nice bike that could have any one of the models above mounted as an interchange. This list is for US models only.

Below are examples of 3D with hooded air screw, a '68 350A, and a '74 722A. All of the models have different tuning changes, float height, etc. The 350A has the largest differences and care must be taken for a proper rebuild as most available kits simply do not have correct parts. Unless your going for a direct restoration, I typically recommend using second gen carbs to make life easier. The bikes will accept them with no mods and they are pretty hard for most to see they are not the early carb.

'71 CB350 3D CB/CL350K3-'72-3D