Tuesday, April 7, 2009

Sea Trials, Fender Woes

I had the opportunity to take 2 rides today to test out the Gran Tourer setup. This bike is being set up as my general purpose bike; I have pretty high standards for what that constitutes. Essentiallly, anything not bulletproof, smooth, and quiet is rejected. Anything short of being hit by a speeding coal truck should not cause rattling, buzzing, or clanking.

Life is too short to be messing around with subgrade parts and setup.

I have to go to Bethesda pretty frequently, about a 4 or 5 mile trip each way. If I chose, about 3 miles each way can be unpaved, with about a mile of that pretty bumpy, large gauge gravel. Blowing down that at an abusively fast pace is an excellent way to test if everything is tight and rattle free.

The first trip got pretty rattly, so I went home and found a few loose items. The pump actually broke free once, so I moved the mounts a little closer together so it is held in by more tension.

The second trip was much less rattly, which is good, and increases the signal to noise ratio for the few remaining issues. It turns out that there are three issues, all with the Velo Orange fenders.

One is the material - my impression is the VO aluminum fenders project more noise from minor grit and whatnot thrown up by the tire than do the Berthoud stainless steels ones to which I've become accustomed. They just seem noisy. Maybe it is something I could get used to.

The rear fender seems to have a little resonant buzz, probably needs some sound silencing pads (strips of inner tubes) where the fender passes near or contacts frame members.

The third issue is the most worrisome - on really bumpy stretches at full clip, I got the impression that the front fender struck the wheel a few times. This is what it sounded like and is not a good thing and possibly a safety hazard.

I had a bit of time to ponder this the rest of the ride home. Initially, I was quite pleased with the Velo Orange fenders, and one part of this was the ease of installation with only one fender mount per stay. Chris Kulczycki explained that with the heavier gauge aluminum, only one mount would be necessary.

That is probably true in terms of preventing fatigue failure in the fender, but if one examines the geometry, it is clear that this results in a less rigid arrangement that will allow the fender to sway more side to side and hence, strike the tire more easily than a two mount arrangement.

This is not good, although I suppose I could salvage these fenders for another bike. I haven't given up on it completely - I'm considering spreading the stays inelastically, then remounting, that way they will be under more tension, maybe this will be the margin of difference. Or perhaps one could use two mounts per stay, which probably would resolve the issue.

But even still, there is the noise issue, although I really need more rides and data to make a judgment there.

However, at the moment, it is looking like these may not be certifiable for extreme duty. This, to me means once installed and set up, I should get years of trouble free service w/no glitches or annoying issues in any sort of terrain to include unpaved and general abuse. In all fairness to Velo Orange, they don't market these things as suitable for 50 mile speed runs down the C&O towpath, etc, and 99 percent of riders will find them ok. They look like a million bucks, anyhow.

In other results:

The Velo Orange front rack is bomb proof. All the other components I've swapped out are ok. The stock chain is noisy. The front brake squeals likes nobody's business, but I've got some toe adjustable pads to throw on there to test out.

All in all, dialing this one in. I sure hope I don't have to pitch the fenders.

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