I am having some clearance issues at the fork crown with the front fender. Out of curiosity, would filing 1-2mm from the bottom of the crown affect structural integrity? It doesn't seem like an ideal solution, but I was curious if anyone has tried doing this on a similarly built fork. From what I can tell, there are several mm between the bottom of the crown and the hole that is drilled through the crown. The goal would be to shave a very small amount of material from the front of the crown to raise the front portion of the fender by a hair.

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Making the bottom of the steerer tube concave to match the contour of the fender is perfectly safe until you begin to nibble at the welds holding the fork legs to the steerer.

You could go with a socket head cap screw and a small pattern washer, or file the washer, for even more room to file.

It looks like the edges of your fender iare against the fork legs, so unless you bend the fender that may limit how far you can move it up.

I would put some Kapton or helicopter tape or similar between the fender and fork so the fender does not abrade the paint.

How much clearance do you have between the tire and the fender? It looks really tight, even if you raised the fender by 2mm.

If I were you, I'd manipulate the profile of the fender and the bracket before I'd start grinding away at the fork. I'd bet that you could get another 1mm clearance easily.

Right now, there is about 5mm or so of clearance between the top of the tire and the front portion of the fender. It's really hard to see between the tire and the underside of the front portion of the fender, but the fender doesn't seem to impede tire motion.

There is a faint squeaky sound every time the tire goes round. It's so faint I wouldn't hear it while riding outside...only when I'm at home alone, and it's quiet, and I put my ear up to the fender. I can't seem to make the sound go away. The tire spins freely--doesn't grind to a halt. I'm wondering if it's the little tire knobby thingies hitting the fender...or if it's rubbing somewhere since the tire is slightly out of round. I have the fender jammed all the way up into the fork, hence the interest in shaving some material from the inside of the crown. If I could shave just a little material off the front of the fork crown to make it follow the curvature of the fender rather than being square, I could raise the front of the fender a bit higher. Thoughts?

It's crazy but in the rear wheel I have huge amounts of space. I really want to stick with this size of tire. Should I just run with it? I've already played with widening the fender profile--problem is that it reduces the overall diameter of the fender.

I would not grind it. If your bolt is tight leave it alone. If it makes noise put some tape where the fender contacts the fork and reinstall the fender.

Those are called "sprues" and I have had them make noise on my bikes too; iI tend to like the largest tires I can fit. A few minutes' work with a diagonal cutter will get rid of them. You should be able to see where it is rubbing, if it is.

If you can you might want to arrange for the rear of the fender to have the closest fit to the tire; if it is larger items which enter at the back through the larger opening may jam when they reach the tighter spot; not fun with a front wheel.

Are these metal fenders? If so, perhaps you could form a properly sized dimple in the fender corresponding to the steerer tube projection.