Ran into a slight problem with mine yesterday. 46 size with a Saito 100, APC 16 x 4W prop. Pulled the threaded section from the back of the blind nuts holding the motor mount on. Three of them just snapped off when I hit the throttle hard in a waterfall. Got a couple of hours on it. Firewall is fine.

I had used the stock mount and it worked with minor mods. Think I should have gone the next size up and put larger blind nuts in the firewall.

BTW, plenty of vertical, even with the engine running rich breaking in.

Ed M.