I don't have it on my current bike...came that way. But I do have it on my first bike, my Trek 2100 WSD. And to be honest, I'm kind of glad it's there and I don't plan on removing it...and here is why. My second bike, a Cervelo, did not have the plastic thingy in place when I bought it. Cool, I thought...since I thought it was ugly anyway. About a year later, I was climbing a hill and somehow my gearing got all wonky. I was trying to get into my lowest gear (big cog on the rear)...when suddenly my chain got sucked into my rear wheel. I have no idea how this happened, but it did...and it snapped my rear derailleur off with it. I needed a new rear derailleur, chain, and rear derailleur hanger...all to the tune of $200 (with labor). Later on is when I realized, that if that stupid, ugly plastic thingy had been there...it would have prevented my chain from getting sucked into the spokes of my rear wheel. Oh well. Not saying you should keep it...but just presenting another perspective. Like I said, I don't have one on my current bike, but I'm always praying that something like this won't happen again.

Linda