I added the large platform to the front of my RadCity 5 Plus, and now it's pretty easy to bottom out the front suspension, even with no cargo on the platform. Just going over a speed bump in the road will result in an audible "clang" from the front of the bike. I've turned up the suspension preload setting to max, but it doesn't seem to change much.

I thought I had a defective front suspension fork, but I showed the bike to two bike mechanics locally, and they think that the bike is just not fundamentally designed for the extra weight of the large platform and front rack (required for the large platform).

Anyone else having this problem? If not, maybe I do have a marginal front suspension fork.  If so, how did you address it?

At this point I think I may need to resign myself to using the lockout if I want to haul any cargo up front.