Menu

Technical FAQ: Chipped clearcoat, old gear and tire issues

  • By Lennard Zinn
  • Published Apr. 6, 2010
  • Updated Feb. 8, 2011 at 8:25 AM EDT

Dear Lennard,
I have Campy Record ergo shifter levers that have performed well since 2000. Over the year’s small chips, cracks and peeling of the outer “glossy” layer have appeared on the brake lever blade. Some of the spots are at the end of the lever – helped along no doubt when my cat took a fancy to them – and some at the brake blade release pin.

I have two questions. First, aside from aesthetics, should I worry about the loss of the clear coat? Second, if I should worry, what’s the best way to repair any damage? I’ve heard nail polish gloss coat is an alternative. Is this true?
Ken

Dear Ken,
No, there is no need to worry about chipped clear coat.

As for patching it with nail polish, I’ve tried that on bikes a lot, since it’s offered in so many colors that you can match the frame color easily without buying a quart of paint. But my experience has been that it is not very durable.
Lennard

Dear Lennard,
Seems like the pros change their bikes quite often. At least a completely new setup once a season. What happens to the old stuff?
Jagdeep

Dear Jagdeep,
It obviously varies widely, but one popular method for teams to dispose of excess equipment is on eBay. There are a few companies here in Boulder that specialize in exactly that, with a fair amount of their business coming from pros and pro teams. Here are a couple of them: www.theproscloset.com and www.gearmovement.com.

And don’t forget our own annual VeloSwap, where you can find some remarkable deals on used pro gear.
Lennard

Dear Lennard,
I recently upgraded to a SRAM Red external bottom bracket. The instructions said that I should repack it about every 1000 miles or after a rainy ride. They also sent a syringe of a blue colored lubricant.

My questions are: What is the best way to go about repacking the BB? I don’t want to take it off the bike every time I do it, so can I do it on the bike? Where can I purchase more of that blue grease? If it is not necessary to buy more of the blue grease, what do you recommend? Is Phil Wood waterproof grease a good idea?
Rob

Dear Rob,
Yes, you can do it on the bike, at least the side that gets dirty.

  • Remove the crankarms. To get the cover seal off to reveal the bearing, slip a blade under the edge and pry it up.
  • Now that the bearing is visible, with a razor blade or knife blade, get under the edge of circular bearing seal between its inner and outer rings and pry it off.
  • If the bearing is dirty inside, scrub with solvent and a clean toothbrush to clean the dirty grease off of the ball bearings.
  • Blow the bearing out with compressed air; (wear safety glasses while you do it).
  • Re-pack the bearing with clean grease and re-install the bearing seal and the bottom bracket cover seal.
  • Re-install the crankarms

You can’t get at the other side of the bearing without removing it from the cup (which is a project requiring a special bearing puller).

Get grease for ceramic bearings from Ceramic Speed.
Lennard

Dear Lennard,
I enjoyed reading your recent article on front blowouts in VeloNews and VeloNews.com. Indeed, I have enjoyed reading many of your articles.

You recently wrote:

There is no way to get a long rip in a tube like that without blowing the tire off of the rim, and there is no way to get a tight tire to blow off of the rim (at least one that is sized appropriately to the rim) without getting some inner tube underneath it to lift it off.

"No way" this can happen? Oh really?

I wonder, when you say “no way,” do you mean “100% of the time,” or are using the words idiomatically to mean “almost always.”

A long rip in a tube was associated with a tire bead problem in the attached photo.

Since you wrote “no way,” do you think the long tube rip must have been associated with some inner tube underneath the tire, or do you think it possible that a tire defect led to the problem?
Arnie Baker, M.D.
Bicycle Racing, Coaching, Sports Science, Medicine & Writing

Dear Arnie,
I stand corrected – “almost always” is more accurate. I imagine it is possible for a tire bead to tear away from the casing like that without the tire blowing off of the rim. It’s pretty rare relative to tires blowing off of rims.
Lennard

Dear Lennard,
Zipp says that decreasing pressure reduces rolling resistance. Nothing is said about the surface being ridden. I cannot understand how decreasing tire pressure can do anything but increase rolling resistance. The less the tire flexes and deforms the less energy is lost. We can discuss how lowering tire pressure helps handling and comfort and how that translates to being faster over a given course, taking into account the surface being ridden. But how anyone can say there is less rolling resistance at a lower tire pressures baffles me and apparently track racers agree.

If lowering pressure actually reduces rolling resistance, as Zipp claims to have found, then why aren’t the track guys running 120psi?
Bryin

Dear Bryin,
The assumption, if not explicit, that I made is that Zipp’s research applies to riding on the road. On the track, it has to do with the smoothness of the surface they’re riding on.

Riding a mountain bike or motorcycle on rough terrain is faster with suspension, and tires, your first line of suspension, act similarly.

As with suspension, the argument is about sprung vs. unsprung weight. If you ride a tire pumped up to, say, 140psi, on a chip-sealed road, every single chip you hit will lift you and the bike, sucking up energy and slowing you down. If you instead ride over that chip seal at, say, 80psi, the tire tread will move up and down over the chips without the wheel being deflected (and hence the bike and rider as well). This will result in lower rolling resistance.

The rougher the surface, the lower the pressure for minimizing rolling resistance. Cyclocross racers run tubulars at 26-28psi for this reason. Believe me, you can feel the enormous additional rolling resistance if you instead ride them at 50psi on most ’cross courses. Obviously, the converse is also true; you can use higher pressures efficiently on smoother surfaces.
Lennard

Dear Lennard,
Thanks for the succinct assessment of virtues of tubulars in VN Tech. I never switched and may be alive because of that. Was sweeping down through a hairpin on Alpe d’ Huez in ’03 when my front tire blew. I rode it out.
Phil

Dear Phil,
Glad you’re still here to tell the story.
Lennard


Follow Lennard on Twitter at www.twitter.com/lennardzinn


Technical writer Lennard Zinn is a frame builder (www.zinncycles.com), a former U.S. national team rider and author of numerous books on bikes and bike maintenance including the pair of successful maintenance guides “Zinn and the Art of Mountain Bike Maintenance” – now available also on DVD, and “Zinn and the Art of Road Bike Maintenance,” as well as “Zinn and the Art of Triathlon Bikes” and “Zinn’s Cycling Primer: Maintenance Tips and Skill Building for Cyclists.”

Zinn’s regular column is devoted to addressing readers’ technical questions about bikes, their care and feeding and how we as riders can use them as comfortably and efficiently as possible. Readers can send brief technical questions directly to Zinn. Zinn’s column appears here each Tuesday.

FILED UNDER: Bikes and Tech / Technical FAQ TAGS: / /

Lennard Zinn

Lennard Zinn

Our longtime technical writer joined VeloNews in 1987. He is also a framebuilder, a former U.S. National Team rider, and author of many bicycle books, including Zinn and the Art of Mountain Bike Maintenance and Zinn and the Art of Road Bike Maintenance, as well as Zinn and the Art of Triathlon Bikes and Zinn's Cycling Primer: Maintenance Tips and Skill Building for Cyclists. He holds a Bachelor’s degree in physics from Colorado College. Readers can send brief technical questions to Ask LZ.

Get our best cycling content delivered to your inbox

Subscribe to the FREE VeloNews weekly newsletter