(bottom engine) These engines undeservedly get a bad rap because they don't scream RPM but have brutal torque instead.
This one will swing a Graupner Super Nylon wide 12.5x6 reliably all day long with ease.
I had two of these engines, and this one has a backplate I machined from aluminum by copying the other one and it works just fine, it just looks a little different because it's not a casting but who can see it anyways?

$ 68 includes shipping, please leave a comment if you intend to purchase so there are no misunderstandings. PM me with your email and I will send a paypal invoice. Thanks