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I purchased a 1981 CM400C with all the parts in a box. When looking at the engine it appears to be a CM400T based off what I could find searching for the stamped number. I'm having an issue in which the engine mounts are not matching up with the frame. I'm wondering if these are supposed to fit, if I need different mounting brackets, or if something is wrong with the frame? The two bolts in the engine that directly mount to the frame do line up, but after I get bolts in there the top mounting brackets and the front mounting bracket do not line up at all.
 

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I'll be doing this same swap, CB400T kick only engine into CM400C so I'll be following this closely. I had wondered about the front and top mount pieces, but they are the very same part number.
 

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Post pictures of the misaligned mountings. CM400t and CM400c engines are identical.
 

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I'll be doing this same swap, CB400T kick only engine into CM400C so I'll be following this closely. I had wondered about the front and top mount pieces, but they are the very same part number.
The mounting brackets may be different. One of the more knowledgeable members may be able to tell you. If not I have a cb400 and a cm450, I can take some measurements
 

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CM400T

CM400c

Check the parts list. Numbers 5 and 6 (upper plates, front mount) are the same. The engines are identical in every way. Pictures would help a great deal here. Something with your frame or how you are installing the engine is wrong.
 

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Post pictures of the misaligned mountings. CM400t and CM400c engines are identical.
So most of us agree that the range of CB and CM 400 engine's mounting points are identical, the front and top mounts having the same part number in fact.

I agree that posting some photos of how you have the rear of the engine mounted, and the misalignment at the top and front mounts, and a wide shot of the whole thing should help us figure out just what's going on.
 

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Moved to SOHC Engine section
The CM frames are all identical with the exception of the 1981 CM400E which had a minor difference unrelated to the engine mounting.
The CM400 engine cases are all the same part number and include the 80/81 CB400.
The rear case bolts need to be loose while aligning the other mounts, there is some slop.
If you can't get all of the bolts to align then I'd say that your frame is bent.
 
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