While Honda OEM manual is the way to go, if you had to just have one, its nice to have several from different manufacturers to cross-reference. Sometimes something might not be too clear and better explained in a different manual.
Haynes and Clymer manuals are all over feeBay pretty cheap - NO reason to pay any more than $25 for either unless you are soooo anal-retentive that you can't deal with some fingerprints on it.
Also, there are many editions of each. Regarding the Clymer manual, look for THIS version:
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Early Clymer manuals use higher quality illustrations (which are straight out of the Honda manuals) while later versions use crappy hand-drawn versions
(I think Honda told Clymer to quit using their images, at some point or something)Here is another manual many of you probably haven't heard of:
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Its by Intertec (sic?) and is kinda neat - it covers ALL the CB cycles, to some degree. Its rather minimal but has real good illustrations and is a nice compliment to other manuals.
There is also the Drake manual:
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Another manual that's nice to have as a compliment to the Honda OEM - similar to the Intertec.
(for those that don't know, I sell automotive-construction-farm-cycle manuals and literature for a living - and no, I don't have any of these manuals currently for sale. 