Fenders and Mixed-Terrain Riding

Fenders or no fenders?  Or, more accurately:  Mudflaps or no mudflaps?  It's a question we often hear.  For riding the road, with others, the answer is generally simple:  If there's any threat of rain, use fenders.  Mixed terrain riding adds a couple layers of complexity to the decision making process.

There is no one perfect answer for all situations, weather conditions, terrains, and riding styles.

We think about five primary aspects to the decision:

  1. The hope to stay dry and clean.
  2. The desire to be kind to riders behind you.
  3. The inclination to avoid mechanicals:  Keeping a stick from getting wrapped up in a rear fender.
  4. The need to ride safely:  The need to avoid a stick getting pulled up into the front fender.
  5. Tricks for optimizing whatever fender setup you choose.

The first and second aspects - staying dry and being kind to other riders - are easy:  Ride with fenders.  

It's the third - and particularly the fourth - aspects that we focus on:  safety.  We've seen fender failures and mishaps too many times over the years.  More than once we've heard of friends that were simply riding along and the next thing, they woke up with an EMT or good Samaritan staring down at a sprawled bike and body.  Too many hospital visits.

Here are some solutions for riding with fenders while improving the odds of a safe ride.  In order of least benefit to best improvement - when compared to a classic metal fender system:

  1. Marginally Safe:  Ride with plastic fenders instead of metal fenders.  Plastic is more likely to yield, deform, and fold under the force of a tough branch.  A plastic fender will not prevent a sudden stop but it does reduce the odds.  If you do have a run-in with a rock or log, a plastic fender is more likely than metal to be usable after the event.
  2. Slightly Safer:  Rotate the front fender as forward as you can get it.  Raising the 'foot' end of the fender will help it clear rocks, roots, and curbs more safely.
  3. A Bit Safer:  Ride with fenders that have fender release tabs.  This, combined with the plastic fender, provides a breakaway effect that reduces the odds of a sudden tree branch stop. 
  4. Pretty safe:  Ride with clip-on fenders.  These allow the fender to move - some would say too much - and therefore are unlikely to tangle with a branch for a sudden stop.
  5. Very Safe:  Ride with a rear fender only.  This eliminates the sudden breaking over the handlebar issue.  While a rear fender can catch a branch and lock up the rear wheel, this a lot less traumatic than the same happening to a front wheel.
  6. Safest:  Don't use fenders at all.  This may seem a bit obvious but if you're riding a multi-day bikepacking adventure and you expect rain, you're going to be soaked at the end of the day anyway.  A front fender is only useful after the rain or during extremely light rain.  A rear fender is, as always, nice for the person behind you but we find during a rain storm, the last place you want to be is right on someone else's wheel - heavy rain hide potholes, road defects, and trail nuances so we tend to give extra room to the lead rider.

We'll dig into the details of these suggested solutions in future posts.

Fenders, like everything in mixed-terrain bikepacking, can be complicated.  More after this photo.

Fifth aspect:  Fender setup optimization.  There are as many ideas on how to optimize fender setup as there are riders on the road.  Here are a few points to consider:

  • Fender coverage:  
    • Front - nose of the fender:  Longer is better the faster you go; if you're rolling at 20 mph, long will help keep grit out of your face.  Some would consider this a safety concern; getting grit in your eye at 40 mph - or at any speed - might be considered dangerous.  The downside to a long nose is that it is more susceptible to long-term vibration fatigue failure.  However, if you have good fenders and they are set up properly, you'll get a couple seasons or out of them.  There are some easy reinforcement tricks to extend fender life, too.
    • Front - tail of the fender at your feet:  Lower or longer is always better for dry feet.  Higher is safer for off-road riding.  If you drop off a rock and catch the fender, you'll be very sorry - at best.  Mudflaps help balance this conflict.  The more flexible the flap, the lower it can go for mixed-terrain riding.  Provisions Unlimited makes a fender mounting system that is extremely versatile - allowing for about 3.5 inches of rotation adjustability to most fender systems.
    • Rear - at bottom bracket:  Any good fender will clip on or bolt onto the chainstay bridge.  This is about as long as a fender ever needs to be.  This is pretty much a fixed point.  Some fenders have an additional cowl to protect your feet a bit better.  You can also modify your fender for better protection here.
    • Rear - tail of the bike:  Because the front end of the rear fender is essentially fixed, the tail of the fender is also fairly fixed - at least the metal or plastic portion is.  Adding a mudflap to the tail can add 4-6" of coverage.  A stiffer rubber flap is more versatile than most aftermarket fabric mudflaps.
  • Mudflaps and extensions:  Some fenders come with molded rubber flaps.  Some are available as aftermarket items.  There are also many fabric mudflaps available.  Of course you can also make your own from water bottles or even simple packing tape or duct tape.  Remember that the more flexible and forgiving the material, the better that is for mixed-terrain riding.  The stiffer the material, the better the foot coverage.

On staying dry:  We find this comes down to two parts of your anatomy:  your rear-end and your feet.

  • Rear-end:  Using a large saddle bag - like a Revelate bag or similar - does a pretty good job of keeping your tailbone dry.  
  • Feet:  There is no perfect solution here.  For cold rain riding, plastic bags and appropriate sock layering work fairly well.  In cold weather, rolling with foot warmers can help tremendously.

On keeping your bike dry:  This is truly a waste of energy.  It's going to get wet, dirty, rusty.  You'll be home eventually and you can sort out the water when you're home.

Some tertiary thoughts about determining when to use fenders:

Taillight:  finding a good place to mount a taillight is always a challenge.  Some people like to use the rear fender as a mounting platform; this is particularly true with hardwired taillights.  Fender mounted taillights are not our favorite for mixed-terrain riding because the light will eventually rattle loose and likely damage or destroy the fender along the way.  Taillights mount better to stiff metal fenders rather than flexible plastic fenders.

Snow Riding:  Snow means no fenders.  Many riders find this out during their first harsh weather ride.  Depending on the temperature and conditions, your fenders will simply get clogged with snow at some point on the ride; it makes rolling a drag.

There are a lot of other nuances and customized fender possibilities - all for future posts.

What fender solution do you use and why?