Lots of reports over the years of people buying Chinese bikes in Accra--there is reportedly an area around "Circle" where this is often done. I've never tried this or looked into it myself.

I've posted before, so won't go into detail again (but suggest a site search): first, many of the larger bikes and familiar adv/dual sport models you'll see in West Africa are illegal, so beware.

Second, I've found it easy to just show up and start asking hotel desk clerks, taxi drivers, repair shops or other local contacts if they know anyone who'd like to rent for a week or so. It usually takes a day or so for someone to turn up with a newer Chinese bike in reasonable repair. Be extremely wary of bikes that have been around the block a bit, since repair standards are not what you're used to, and be sure to figure out insurance, carry documentation covering the bike and the owner's permission to ride it.

Best deal I had was for a few weeks two years running when the bike I found was government-owned and rented to me by a low-level bureaucrat. Riding that one, I breezed through police checks and never had any breakdowns. Another year I rented an almost-new Chinese "jungle bike," i.e., dual sport styled to look like a trail bike, from a hotel clerk I'd never met before. Of course, I also once paid too much for an unremarkable Japanese 200cc, and another year ended up with a totally unreliable older 650. Caveat emptor.

Hope that's helpful.

Mark

Edit to add: There's lots more involved in riding in West Africa. Think it through, read some trip reports, and be careful. Also, even in Ghana, keep your ear to the ground about civil unrest and banditry.