Any bike tourist or commuter knows that if you’re going to bike in the rain, you want fenders. After searching online, I only found one obvious choice for the Ogre: Planet Bike Cascadia 29er fenders. After reading a blog post from Surly and other info posted by Ogre owners, I knew there were a couple challenges involved. The biggest problem is ensuring you have enough clearance between the rear tire and the front derailleur.
The Ogre came with a couple “monkey nuts” which push the rear axle back a bit (14 mm?), but that’s not enough. I rode over to Salvagetti to buy a chain tensioner (or chain “tugger”) to pull the rear wheel back a bit more. The Surly Tuggnut tensioner is $30, not cheap! But Salvagetti had some $10 chain tensioners by Redline. I bought two since I thought I’d need one for each side. Once home I realized the thickness of the tensioner would require a longer quick release skewer if I wanted to use both. Turns out you really only need a tensioner on the drive side to keep the wheel from moving forward under heavy pedaling. Oh well, now I have an extra tensioner for future use.
One problem with the Redline chain tensioner though. Notice how it contacts the rear dropout:I didn’t like how little of the tensioner was in contact with the flat part of the dropout ends. So I took a file to the tensioner to improve things. Here’s how it looks after filing down one side, and then with both sides filed down compared to the other unmodified tensioner:
Look how much better it now fits against the rear dropouts:The Surly tensioner is shaped like this already. So for an extra $20 you can save yourself some filing. However, there are a couple benefits to the Redline tensioner. First, it’s aluminum and so a little lighter. Second, look at the reverse side of both tensioners:
Notice that the Redline tensioner sticks out a bit between the two holes. When the axle is in the rear hole this little tab pulls back on the axle. The Surly tensioner surface is smooth so it can only pull back on the quick release skewer. I’d rather have the version that pulls on the axle.
Now, a note about the monkey nuts (the black thing in the dropout in the photo above). I left the monkey nuts in the dropouts even though they don’t really serve any purpose. Why? Because if we’re on the road and some problem occurs with the chain tensioner I’ll already have the monkey nuts on hand as a backup. Such a situation might require removal of the rear fender to avoid rubbing the front derailleur, but that’s ok for a short-term fix. Also, I positioned the monkey nut on the non-drive side so it helps align the axle when putting the wheel back on the bike. This makes it a little easier to make sure the wheel is straight and helps ensure the rear brake disc isn’t rubbing.
With the chain tensioner taken care of, the rest of the rear fender install was pretty easy. Here’s a photo of where the fender attaches to the seatstay bridge: I used a scrap piece of metal to extend the fender mount point. This allows the fender to be closer to the tire. It would work fine without this modification, but I think this looks better. Next let’s look at the lower fender mount points:
I found it worked well to mount the fender to the inside of the rear mounting hole above the dropout. I had to move the rack to the forward mounting hole. I could have used a longer bolt and put them both in the same hole, but I wanted to move the rack forward anyway to make the top of the rack more level (see previous blog post).
As for mounting the fender to the chainstay bridge, I also did a little modification there. The fenders come with two 30mm tubular spacers. I installed one and decided it was just a bit too long so I cut it down to about 22mm. Here’s how it looks installed below the front derailleur:
Notice how the back part of the rear fender is pushed away from the tire? That’s necessary to allow removal of the rear wheel with an inflated tire. I have a pair of Schwalbe Big Ben tires on order. Once those arrive I’ll re-check the fender fitting and adjust as needed. I might keep the fender closer to the tire and just be aware I need to loosen the fender (or deflate the tire?) before removing the wheel.
Update: I installed the Big Bens (28×2.15) and they’re a great fit. I was able to move the back part of the rear fender closer to the tire and I can still remove the wheel while the tire is inflated. The slightly smaller tires provide a bit more space all around, which is what I was expecting.
Here’s how I chose to mount the fender struts to the lower part of the fork: I used the mounting hole that was available on the Tubus Duo rack. The lower mounting hole on the forks (seen in the bottom of the above photo) wouldn’t work due to the disc brake being in the way on the left side. Here’s a view of the fender mount point from the inside of the fork:
Since I mounted the fenders to the Duo rack, the upper fender struts were a bit long and were hitting the frame’s down tube. I cut about 2 inches of metal off the upper fender struts to clear the frame.
Update: On her first ride, Caroline’s toes hit the lower fender struts a couple times. So I cut those down by a couple inches as well.
While I’m on the subject of protecting the bike from dirt and grime, let me show off a chainstay protector I created based on and idea I found on mtbr.com:
I took an old inner tube and cut it into a long strip as straight as I could. I then wrapped it around the chainstay starting at the rear dropout. I taped both ends and, voilà! I think it looks pretty good and hopefully it will stand up to a lot of abuse.