MILL/DRILL Spindle Speed

Hello,

I have a RongFu 30 and would like increase the max spindle speed from
2500 rpm to 5000 rpm. Has anyone done this ?

My plan is to change out the stock 1700 rpm motor with a 3400 rpm
motor, thus doubling each of speeds. My concern was the spindle and
other bearings not being able to handle the faster speeds. Could
this be an issue ?

Any ideas or concerns would help.

Thanks,
Joel
http://www.jhchoppers.com/cnc/