Making Mudflaps for your Fenders

Old Style New Style

Why Mudflaps

Full-length bicycle fenders are very handy for riding in the rain, because the keep mud and grime off of you, your drivetrain, and your friends. These qualities are improved with mudflaps. Its pretty easy to make your own with a small amount of time and a couple of basic tools.

The front mudflap is useful for keeping rain and street grime off of your feet and drivetrain. The rear one is useful for keeping the grime from spraying up off of your rear wheel, into the faces of fellow riders.

Parts and Tools Required




  1. Cut the rubber to be the same width as your fender (or a bit wider). I do this by putting the rubber up into the fender, bending it into the shape of the fender, and marking off how wide it needs to be. On my most recent mudflaps I have been making the lower part of the mudflap wider then the top part. I find that making the base about 2" wider then the top works well.
  2. Drill two holes in the fender, about an inch apart.
  3. Drill one hole in the rubber, about 1/2" from the end.
  4. Bolt the rubber to the fender using the top hole.
  5. Drill through the fender into the rubber, making a second hole in the rubber. You could also measure and make the holes in the rubber line up.
  6. Bolt the the rubber to the fender through the second hole. The rubber strip should now be hanging down from the fender. It would be a nice mudflap, except that its too long and trailing on the ground.
  7. Cut the rubber strip to length. I like to make my mudflaps really long, making the end about an inch off of the ground.
  8. Optional: Add reflective tape going down the fender and mudflap. I've been told by cyclists riding behind me that this is very noticable and effective in helping traffic see me.
  9. Optional: If the mudflap blows around a lot then you can add some washers and bolts to the bottom of it to weigh it down. I've found that this isn't necessary with my wider mudflaps.


When making my last set of mudflaps I spent more time making a template to get the most use out of one piece of stairtread rubber. I was able to get three sets of mudflaps out of one piece of rubber, but two of them are smaller then normal (for the 20" wheels on my Tandem Two'sday). My new mudflaps are also wider at the bottom then the top, which makes them a bit more effective and getting them perfectly aligned with the fender is less important.

These mudflaps are 10" long (rear) or 8.5" long (front). This brings the lower edge about 3" off of the ground in the rear and an inch off of the ground in the front. Longer mudflaps could be cut using the same template if you prefer to have them lower the ground.

To prepare the stairtread I cut off the rounded lip. This leaves me with a piece of rubber about 10" wide and roughly 30" high. I then drew out the following template:


(Click on the image to get a larger version of it)

You can then secure these mudflaps using the instructions found above. I will update this page with pictures of the mounted version of these mudflaps in the future.

Commercial sources for similar products

Cobbworks, the makers of the Oyster Bucket Panniers, have also started to make very nice looking mudflaps. I don't know what these cost, but if you are short on time they might be a good alternative. They are triangular (similar to the ones in my template above) and come covered with very high quality red reflective tape. The Cobbworks webpage has contact information.

Hunt Wilde (a bicycle accessory manufacturer) also makes rubber mudflaps. I don't know much about these, although the ones that I've seen have been shorter then I like. Your LBS should be able to special order these. The product number is 0009-055.

I have more bicycle information on my main bike page.