I recently bought this 1970 Motobecane 40V with an AV7 engine. I'm planning to replace the engine with an AV10. Keep you posted on the progress... I've been working around the brakes, wheels ans suspention part, installing a brake disk on the rear wheel, and replacing the origianal fork with an Peugeot 103 fork. I have found some Grimeca wheels in France for a bargain price and adappted them with spacers for installing the 160mm disk. The second hand Brembo rear brake is ideal for this project.