I have a 26" Scwinn del mar cruiser single speed bike. I changed the coaster back wheel for a mountain bike wheel. I put a front fork with suspension and built in side pull caliper brakes from a roadmaster sx mountain bike(I put this fork on cause i needed brakes since i removed the ones from the rear). When i apply the brakes the forks bend a little out toward the front of bike in the shock area, is this fork or suspension wore out or broke? They move around a 1" or 2" . If i have to put the old stock forks back on, what kind of brakes should i buy, theres a hole where the fender is mounted to mount brakes.