Mamba Max fan mounting

[mtucker]

I am not having much luck keeping a fan on my Mamba Max ESC. I bought two 25mm Sunon fans (3.5 CFM airflow). They are nice and small, but still move a decent amount of air. The problem is the three support arms that go from the fan shroud to the rotor/blade are very thin and weak. I think the big jumps at the race track are causing the arms to break. That leaves the shroud well mounted, but the rotor/blade flopping around.

I used two #4 screws to hold the fan to the heatsink of the MM. I also used small washers to slightly lift the fan off the heatsink. My thinking was if the top of the heatsink wasn't flat it would put a lot of stress on the fan when I tightened it down.
Now that both fans have broke, I think maybe I should have mounted it flat and used some double sided thick sticky tape as a cushion. I would need to put the double sided tape not only under the rotor, but along the shroud. The tape would at least keep the weight of the rotor from pushing down too much on a big landing.

I tried to find a Novak fan at the LHS to see if it was a little more beefy, but they were out. Any suggestions for a beefier 25mm fan or mounting is appreciated.
For now the cool winter nights let me run a full 15 minute main without a heatskink, but I will definitely need a fan when it warms back up.

Thanks,
Matt