I have all my stock belt guards, and still get stones and stuff in my belt. I have to inspect ever day or two. Go figure

 

I took the upper and lower belt guards off of my '09 Street Bob. I have a LOOOONG gravel driveway. I went without an upper and lower guard on my last cruiser (Warrior) too. Never had a problem. Even pulled the um... I think it was the lower guard on the chain of my gsx-r that I just sold. Never had a problem with that either. I'm sure that something bad COULD happen without the belt guards. Just hasn't happened to me yet. But then again something bad COULD happen to me each time I get on the bike. But... I'll still ride.

 

I left the top guard b/c it looks cool, but i took off that ugly black plastic one!

 

Yeah, didn't like the look of the plastic lower guard so I added the chrome cover. Did a perimeter PVC bead between the two when I added it; figger'd it would help keep out dirt/water and prevent any rattle...very solid now.
WS6: Your guard mods look great; odd that your stock lower didn't match the curve of your sprocket. I like the cut-out you made.

 

I ride without the upper but with the lower..go figure...no problems so far!