This Space for Rent

Score: Leif Erikson Drive 1, Velo Orange fender 0

Whoops!

I went for a loop in NE/N/NW Portland this afternoon, and my return was via Leif Erikson Drive in Forest Park. It’s not paved, and it’s kind of bumpy, and today I was moving fast enough to vibrate the chainstay bridge fender bolt right out of the chainstay bridge and onto the road.

It made the rest of the trip back home a little more interesting, because the bicycle kept making the most amusing clattery noises every time I went over a bump.

Comments


I have myself – in my case is was a rear rack bolt to the dropouts rattling loose – become partial to either nylocks or a washer-lock-washer-washer sandwich, and then tightening the bolt enough that the lock washer shows visible curve.

Locktite is supposed to fail above a certain torque (or you might as well weld) and my (limited) experience of the stuff is that the only time it really holds is on ISO brake disc bolts. Which is perhaps a function of being provided already on the bolts (and thus possibly industrial-grade) and getting tightened to a set torque. I’ve never had that much luck with it on anything rack-or-fendery.

Graydon Saunders Sun Feb 12 09:20:52 2012

I strongly suspect that a major reason why that bolt ejected itself is an artifact of the historical reenactmentness of the VO fenders; the old SKS fenders had two sets of rear stays on the back wheel, while the VO only has one. There’s a loooong unsupported beam between the seatstay bridge and the (lower than the rear taillight) stays, so it vibrates like mad on any sort of rough surface.

I’m going to have to get a second stay for the rear fender before the spring rando season begins, because I’m trying to build up a mostly-gravel 200k and that will definitely be a stress test on the poor fender.

David Parsons Sun Feb 12 13:40:27 2012

I have seen it asserted that the single thick stay of the Velo Orange or Berthoud style mounts is in fact stiffer and stronger than the two stays made out of wire used by SKS.

I have absolutely no idea if this is in fact true; I sure hope it is, because I’m planning to switch to Berthoud fenders (and wider tyres, so switching back wouldn’t be completely straightforward…)

Graydon Sun Feb 12 19:44:48 2012

They might be stiffer and stronger (though you don’t need that much strength to hold up a u-beam) but they still only support the fender in one place instead of in two. Two of my randonneuring friends have reported their metal fenders breaking in half at the seatstay, and the only plastic fender I ever had break was a single-stay Planet Bike fender on my xtracycle – the span between the brake bridge and the stay was about the same as the span between the seatstay and the fender stay on metal fenders.

And for that matter I don’t think that stiffer is necessarily a good thing. My VO fender tries its damnest to rattle out that seatstay bolt every time I ride 10+ miles on gravel and/or dirt, while more flexible stays might soak up some of the vibrations before they make their way to the fender.

David Parsons Sun Feb 12 20:18:16 2012

Comments are closed