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CB200 Intake Manifolds. Can I use 306B?

6806 Views 3 Replies 3 Participants Last post by  Simo
Hi folks

As I told you in my CB200's log, I bought wrong intake manifolds few weeks ago... Everything was set to start the engine and the manifolds spoiled my happiness... Back to search for the right ones.

Once is very difficult to find the original rubber manifolds here in Brazil, I'm here to ask to the masters: Can I use the aluminum manifolds in the pictures below? In both of them is written 306B, wich I assume that's the part number, right? Simo advert me about the need of insulators on aluminum manifolds. Do you know where I can find them to buy? (or how can I build them?)

Thanks a lot, folks.

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First, let me state that I have not actually swapped out the aluminum CB/CL 175 manifolds onto a CB/CL 200 engine.....
So, all that I will now tell you is based on my experiences swapping carbs , insulating blocks, and manifolds on other Honda models, but the principles are the same....

Basically, the insulator block is just a non heat conductive plastic spacer, with a paper gaskets to assure sealing..Essentially a very thick gasket...
The critical measurements are the size and placement of the larger center (bore) hole relative to the mount bolt holes.....
Some blocks have all three holes on a single centerline, some have the bore hole somewhat offset from the mount hole centerline......
Some actually have a taper or slant built into them, but I believe the ones you will need are just flat.....
Many similar insulators are used on the "Chinese-Clone" and scooter engines and can be obtained in a variety of bore sizes...
Other Honda models have some that can be easily (and only slightly) modified to work.....(You'll likely have to "oval" or "slot" the mount holes)

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Ill have to check, but off my head 306b is the cb175 manifold so will work carb to manifold, as Steve said chinese scooter insulator and sand paper for fettleing between the insulator and manifold and smooth the transiton to the head
Youll also need longer studs in the head
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