MK Fenders – Part II – The Install

In the last installment I talked about the drool worthiness of these MK Fat-bike Fenders. There is no doubt about it, these fenders look fantastic. However, no matter how good they look, the ultimate question is how do they perform? Well, before we get to that, there’s the install. These fenders install similar to other fenders I’ve worked with (namely Hanjos) so I was fairly familiar with the ins and outs of installing this type of system (drilling holes, aligning braces, etc). If you haven’t done this type of install before, just remember to take your time.

As stated on the MK website, each fender install is a custom job* and mine was a probably a bit more custom than normal. My frame is narrower at the seat and chain stay bridges than other frames so there was some interference. The other big issue was that my stays aren’t drilled so there wasn’t the necessary anchor points. With a little grinding al la a Dremel tool and some simple MacGyver engineering with a few clamps at the bridges, I was easily able to overcome these obstacles. Another issue I had was that the thread size of my fork bridge was larger than the thread size of the standoff and setscrews. A quick e-mail to MK solved this and they had a standoff with the correct thread size in the mail right away. Once you figure out any issues you may encounter, installation is fairly straightforward and laid out pretty well in the instructions (available on MK’s website). Overall, the fenders took me less than an hour to install (once I addressed the above mentioned issues).  The hardware is really well thought out which leads to a nice, solid installation.  Unlike some full coverage fenders I have for my other bikes, the MK’s don’t feel flimsy at all.  Below is a photo tutorial of the install.

Fenders and Mounting Hardware


Standoffs and sets screws – these are used at both the fender and frame attachment points to secure the fender braces. The longer setscrew goes into your frame, the standoff threads onto it, and a smaller setscrew goes in the other end of the standoff to secure the fender brace in place.


Lots of bolts, washers, and short brace rods as well.

Front Fender Install

The front fender instillation was pretty straight forward and went exactly according to plan (and MK’s directions).  The biggest thing to keep in mind is measure twice, drill once.  You don’t want to poke a bunch of unwanted holes in your fancy new fenders!

Measuring position of the fork crown standoff. I used the suggested 6” setback as a starting point and adjusted from there.


I used a punch to mark the spot and then drilled away. I used a piece of wood as a brace to drill in to. This helped reduce chipping of the finish


Standoffs are installed with a plastic washer to create a soft contact point with the fender.


Metal washers go on the underside for reinforcement. Additionally, MK suggests that you use silicon caulk on all holes and blue Loctite is used on all threads.


The fork bridge uses a standoff and a rod bracket which then attaches to the fender standoff. Due to the offset nature of my fork, the bracket is skewed to one side.


The fender braces are then attached to the fork standoffs. The standoffs at the fork legs allow for a little adjustability to account for wheel arch. The excess fender brace is then trimmed off.


MK suggests that for fenders this wide, two standoffs are used for the brace. You then have to put the fender standoffs on the brace and then install them onto the fender. If you install the standoffs on the fender first, you won’t be able to pass the bend in the brace through both of them. Due to interference with the brake caliper, I had to mount the standoffs/brace 8" from the bottom of the fender (vs. MK's suggested 4").


After a little adjustment to line things up, the front’s all done.

Rear Fender Install

The rear pretty much follows the same procedure – measure, mark, drill, install standoffs on the fender and frame, install braces, and adjust. One difference is that with the rear, instead of using standoffs at the seat/chain stay braces, you mount the fender directly to the stays using the holes located in the braces.  However, this wasn’t the case for me due to a couple of issues.  A custom install shouldn’t be without its issues, right? . . .

My frame was too tight in the seat and chain stays so I had to come up with a solution to get the fenders closer to the stay to eliminate tire rub. Additionally, my seat/chain stay braces aren't drilled so a solution was needed there as well.


I used a dremel tool to make clearance for the seat/chain stays. With some careful measuring, and going a little by little with the Dremel, I got the placement just right.


That didn't hurt too bad. Notice the single bolt needed to mount to the seat/chain stay braces. As with the front - measure, mark, and drill. One hole at each of the bridges, and two for the fender brace standoffs.


Exposed wood surfaces were masked off and then covered in liquid rubber to seal them up and buffer against frame rub


All ready to be mounted.

Rubberized and all set to be mounted.


To address the lack of drilled seat/chain stay bridges, I used cable clamps with old inner tubes to attach the fenders to the frame.


Once installed, they worked really well and are barely noticeable.


As with the front, two standoffs are recommended. Placement of these standoffs was dictated by the rear brake caliper as well as the available length of the braces, which in my case were a little short so the brace is mounted a little higher than I would have liked.


Fender brace standoff at the seat stay. I didn't have any etxtra brace to trim off for the rear.


After a little tweaking of the seat/chain stay bridge clamps and the fender braces, things lined up just right and the rear is ready to go.


Finished and ready to ride.

Next up  . . . Part III: A Short Term Review

*Mark from MK Fenders will be offering a pre-drilled option for their fenders to aid in the ease of installation.

, ,

2 Responses to MK Fenders – Part II – The Install

  1. Tom February 21, 2012 at 1:00 pm #

    One strut in the rear? How much room is there between the fender and the rear tire? It looks a little tight. Is it because the seat stay & chain stay bridge is to close to the wheel or is the fender not big enough?

    • Julio February 21, 2012 at 2:15 pm #

      I used one on the rear since that is what they have done on other fat bikes I’ve seen with MKs (both in person and pictures on their site). It’s plenty sturdy with just one so I really don’t see a need for a second.

      Tire clearance is a little tight but not too bad. I haven’t had any problems so far and I’ve ridden them in some really sloppy conditions. The fenders are plenty big enough. Its the bridges that limited how much clearance I could get. I’ve seen them installed on a Pugs and you get a whole lot more clearance because of the curved bridges.

Leave a Reply