Depending on what you’re trying to ride, my beach cruiser never had any problems with dirt roads, sand or trails that were for 4x4. Now it wasn’t going off jumps or crazy trail rides, it was quite heavy for that. If I wasn’t concerned with dropping it, I’m sure I could have pushed it quite farther than I did.
Stock from end, progressive springs and adjustable preloads.
It wasn’t better than a 70s dirt bike, but it could transition to the highway and cruise at 75/80 all day, which a dirt bike of the 70s couldn’t.