Fat tires are great . . . we all know that. They give us super flotation on snow and crazy grip on dirt. But they can also kick up an awful mess of mud and other stuff when conditions are right.
Over the last year I have experimented with different designs to keep both me and my bike clean.
I have tried mounting one to the rear rack bolts . . .
Attaching under the seat . . .
However the most successful design is based on this template.
The material comes in many colours and is easily sourced wherever there is snow. Crazy carpets. For under $5 you can have enough material to outfit several bikes. I have also seen place mats or flexible cutting boards made from the same material in dollar stores.
One afternoon I thought I would swap out the black with a little colour.
Its as simple as trace with a sharpie . . .
Cut with normal scissors . . .
Drill out the mounting holes.
I mounted them to the bike with black zip ties that I got from a dollar store.
Here is the PDF of the template for the front and the rear fender. Tape the two 8.5 x 11 pages together and that will make the front fender.
Lengthening the square end will give you the rear fender.
The frame fender is 5" wide and 18" long (the full width of the crazy carpet). Cutting it this way uses the natural rolling of the material to make a nice curve in the fender.
Have fun !!