Topic: rim swap?

[pinnacle]

will 1978 cb400 comstars fit on the 78 cb550 without to much mods have a chance to pick some up that became available?

[Triffecpa]

it's likely that the axle sizes are the same diameter, so that bit of the puzzle will be easy.  more than likely you will have to make up new spacers to center the wheels front and back.  On the back, you may need to alter the depth or height of the cush drive.  no way to tell without measuring both.  Up front the Comstar wheels take the newer 5 hole rotors which likely have a different offset than the CB550 rotors and they are thinner.  So the front brake system would have to be revised. 

So on the scale of wheel swap difficulty, it sounds like about a 5 out of 10.

Probably exceeds the "minimal mods" level that you mentioned though.

TR

[cb650]

I think the cm had a 18" front also.

[754]

I have 750 F ones. should look and see what sprocket bolt circle is as, 500/550 is rather small.. also whether sprocket can "move in"

comstars tend to be skinny anyway, the 400 might be sorta narrow.

Comstar discs(not sure of dia) are thinner  (could be solved by milling mount bracket), if you use the whole 400 front wheel and fork it may work.