I 3D printed a surprisingly effective bike mudflap
I've been having a problem with my bike in the rain for the last number of months. Some time ago I lost both of the mudflaps that were attached to my bike fenders. I don't know when it happened. I didn't expect to find easy replacements, and I didn't think I'd really need them because I eventually forgot about their utility. Until it started to rain a lot again this season.
I kept on getting a bunch of water spray my backside; it was the dreaded "stripe" or skunk stripe. I was surprised that this was happening because it hadn't been an issue before, and I thought my fenders had me covered. I was getting a ton of road grit all over my panniers and rack, and it was making a mess inside when I brought my bags in. I didn't remember it being that bad before.. and it wasn't. Eventually I noticed that my rear wheel was still spraying water forward despite the fender - it didn't have enough coverage without the mudflap. And the mudflap had fallen off. Or broken off.
Finding and printing the bicycle mud guards
I did a quick search on Thingiverse and found this nice design by Fablab Ideenrich. I was kind of skeptical but I decided to give it a go. They looked thin, they were designed to be printed with TPU, a flexible plastic. I only had white and wanted to print in black to match my fenders, but decided to just print them anyway.
The mudflaps were surprisingly thin. They were way more flexible than I'd like, but at the same time I appreciated that they were really lightweight and didn't use a lot of material.
I wasn't sure how to install them, but then saw that I could reuse the screws that attach the fender struts to the fender with the mounting holes of the mudflap.
It was a little hard to get it centered, mostly because the 3D printed bike mudflap is so flimsy. But I got it to work eventually.
Riding with the new mudguards
I was actually excited for the next rain so that I could try the mudguards. Initial results were great. The rear bike mudflap prevented any water from spraying onto my back or butt. The insides of my panniers were way drier and free of road grit. I looked back when riding to take a look and still saw some road spray that was vertical. But my rear bike tire was no longer spraying water towards my back.
I 3D printed another one for my front fender, and mounted it in the same way. I had been having problems with my shoes getting really wet in the rain. Without a bike mudflap on the front fender, my fenders as they existed would direct water onto my toes when my pedals were in the forward position. This was no longer the case with the new bike mudflap on the front fender. Water was instead splashing off of the mudflap and onto the ground. The bottom of the new mudflaps is only 4 inches or so off of the ground.
What would I change if I were to redesign these bike mudflaps?
All in all, these were fantastic. Way better than my situation before, so I don't have any complaints. I'd make some changes if I could.
The feel a little flimsy. Sometimes in the wind, they flop around enough to rub on the tire. This is not a big issue at all as they barely rub if they do.
I'd 3D print them in another color. I'm sure something goes better with a black thermoplastic fender. Black? beige? light blue to match my frame?
I'd make them longer? The rear one could probably be longer so that there's no vertical spray at all.
If the fenders were stiffer, and longer, they'd hold their curve a little better and I'd have a little more clearance from the rear tire.
But all of these are minor changes. I'm super happy with these bike mudflaps and you can print your own if you want by downloading Fablab Ideenreich's design on Thingiverse.
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