50" is wide for woods. My 250R is 481/2" and I've been in some XC races (with another machine) and I knew my R wouldn't have made it thru.Custom a-arms to widen or shorten.
Like 1 fella mentioned, put your money into shocks.

 

The guys here are leading you in the right track. For most XC racing, 46-48" wide is usually ideal with 22-23" front tires and 22" rear tires. With that said, Setups all depend on the type of trails your actually going to be running. Some XC racing is done on courses that also accomodate to UTVs while others were originally designed for dirtbikes.

Here's a video of my brother and I on what is a typical trail in central NY. Both Honda 700s in the video are 48" wide and on 22" tires all the way around. If you plan on racing in tighter areas, I'd stick to around 46-47"

 

Its not even so much if your quad will fit, its how much room you have on the trails. If you barely fit, then you have to always be conscious of how much side clearance you have and slow down or you"ll hit something. I've seen this a lot with utvs on some trails. They will fit but they can't go as fast as atvs because they barely fit and turning radius is much wider as well. Even saw this at a riding park locally. The trails were originally wide enough just for atvs and 50" rzrs. But as utvs have become more popular in the last few years, all of the local atv parks have widened their trails. But the ultra wide machines like a Rzr 1000 XP or Wildcat 1000 barely fit. If you have something like that, you can't keep up with an atv because you just can't go as fast without plowing into a tree. I like those tight trails you ride on HondaR24, its fun to zip through the woods on a fast quad.