hard engine-braking in second gear- will this wreck a 904/727?

The 904 intermediate band is sorta narrow. But there are kevlar bands on ebay for cheap, plus maybe you could fit in a 1.6" band to replace that 1.4". You could get creative and even install a much wider band just offset the struts; a la sixties Cruisomatic. I'm fitting a 2" FMX kevlar band into the 904 by offsetting the struts. It overhangs the front of the drum a bit.