rishio

I'm getting a new folding bike and I've been thinking about fenders for one purpose - to protect the bike and not to protect myself. I won't be installing a rear fender on my bike due to various technical reasons - but I've been thinking of installing a front fender. It seems as though the purpose of the rear fender is mainly to protect the rider from the dirty water where as the front fender seems to serve more of the purpose of protecting the chainring and important elements of the bike.

So my question is:

1. Is the rear fender protecting important elements of the bike? How so?
2. If I can't install a rear fender, would I benefit in protecting the bike by installing just a front fender?

BlazingPedals

I don't like muddy water being flung in my face, but I doubt a front fender would protect any part of the bike that needs protecting.

Metzinger

The rear fender prevents water from flinging onto the seatpost. It then can run inside the seattube and foul the bottom bracket. If the fender goes all the way down the front of the tire, it can prevent spray from hitting the drivetrain.
A full front fender can protect the drivetrain also, provided it extends close to the ground. Stubby sport ones mostly protect your lower headset race. A neoprene or rubber gasket would be easier to install.

wahoonc

IMHO only using one fender or a very short fender is kind of like only wearing half a rain suit, something is going to get wet. Front fender if of a proper size protects the rider's feet and front side, the bottom bracket area as well as head set and handlebars. Rear fender protects the rider's back side, bottom, saddle, seat post as well as providing some protection for the entire drive train (derailleurs front and rear). The only bike I have that I ride without fenders is my MTB that I use for off road trail riding. Everything else gets fenders and many of them get mudflaps to extend the length of the fender to provide maximum protection.

Aaron

dynodonn 

Since I don't ride off road on anything more serious than flat graveled pathway, I use full lenth PB Cascadia fenders with mud flaps front and rear. The full fenders, with their mud flaps, keeps the road grit accumulation to a bare minimum on my panniers and drivetrain in wet conditions. When I used shorter fenders, it was almost like having none at all, since my gear, bike, and I were usually covered with grit after every wet condition commute. OT, the front fender, if long enough, plays an important role in keeping road grit off the chain and front rings.

Artkansas 

What I used to do in the desert for a "rear fender" was put a folded "weekly news magazine" on the rack. It extended off the back and caught enough of the wheel spray to be helpful.