Hijacked: Technical Q&A with Lennard Zinn RTMS

I have a lot of cycling-related fantasies: establishing our own nation with our own cheese; arranging a bike joust between Barack Obama on his dork-cycle and outspoken eco-nerd Ed Begley, Jr.; and of course the complete eradication of the pie plate. Unfortunately, all of these scenarios are pretty unlikely. But there is one fantasy of mine that's a bit more attainable, and that's taking over VeloNews tech guru Lennard Zinn's Q&A column. Sure, VeloNews isn't going to let me do that anytime soon, and I missed my best chance to steal his identity by not recovering his stolen laptop, but thanks to the internet (the ultimate tool for self-delusion) I can at least steal the questions from an already-published column and answer them myself on my own blog. So here goes:

Techical Q&A with Lennard Zinn Rip Torn’s Mug Shot – Time to replace?

Mix-and-match

Dear Lennard,

At one time I read in your column that you can change Campy 9-speed ergo shifters to 10-speed. Is this true and what are the details?

Guido

Dear Guido,

Sorry, Lennard stepped out for some Pringles, but allow me to help. My answer to your question is three-fold.

1) Yes, you can do it as long as they're not the old ones with the vestigial pointy tops. (Campy ergo levers used to have vestigial pointy tops before they realized people might actually want to put their hands there.)

2) The details are you stick a new shifty thingy in them.

3) I'm honestly surprised that in 2008 people a) still have 9 speed, and b) if they do would bother to “upgrade” to 10 speed at this point. Even though all you need to do is stick a new shifty thingy in them, you might as well throw them out because Campy is going to 11. This is a tremendous leap forward. It means: 1) you can have an 11-21 straight block; 2) those neutral wheel service techs will once again have to work for a living since not everything’s 10 speed anymore; 3) you can have a 20-30 straight block (in the event they decide to make one for some crazy reason). Also, best of all, it means that the Spinal Tap "it goes to 11" reference may finally be beaten completely to death, which would be great, because I'd love never to hear it in relation to road component groups again.

I should warn you, though—if you do go for the new 11 speed Campagnolo, it’s ugly. Really ugly. It looks like the bastard child of a Shimano STI and a Mektronic lever. Although if you’ve already got one of those stupid Pinarello Onda forks then the new Campy is a must-have if you want to retain that melting theme throughout the front end of the bike.

--RTMS

When to replace?

Dear Lennard,

I have two Shimano 10-speed groups: Dura-Ace and Ultegra. I've put about 3000 miles on both groups (I ride my Ultegra bike a lot more in crits and early season training), but I've noticed, aside from the shifting, that my pedal stroke seems "easier" and more supple with Dura-Ace.

So, I have a few questions for you:

1) What's the average lifespan of Dura-Ace and Ultegra bottom brackets? Do I need a new Ultegra bottom bracket?

2) Is there any easy way to determine when they're about to go (other than mileage)?

3) With the old spindled bottom brackets you could rotate the bearings by hand and "feel" the drag/crunch/friction indicative of a need for a new bottom bracket. Now, it's a guess based on "ease" of spinning the cranks, and that can be dependent upon bearing load?

4) Do you know the bearing-loading values for Dura-Ace and Ultegra bottom brackets (would I use a torque wrench for that)?

5) Have you heard of or had experience with the bearing overhaul kit, which I believe is made by Phil Wood?

Mark

Hi, Mark. Sorry, Lennard stepped out to take his ferret for a walk, but allow me to help. The reason your Dura-Ace feels "easier" and "more supple" is that you paid more for it. I always find it puzzling that people reserve Dura-Ace for the fair weather race bike, and use Ultegra or lower for the rain bike or beater bike. Since Dura-Ace is the best, wouldn't that be the logical choice for adverse conditions, since theoretically it should hold up better? I mean, it has "Dura" in the name. At any rate, to answer your questions:

1) You can kill a bottom bracket in about 35 seconds by installing it improperly, yet it can live nearly forever if you rarely use it. (Barring nuclear catastrophe, asteroids colliding with the Earth, Fixed-Gear Apocalypse, and so on.) So by averaging 35 seconds and 100,000 years, I come up with 1,567,800,000,018 seconds. So that is the average lifespan of your bottom bracket. Do you need a new Ultegra unit? If you're somewhere inside that window, maybe.

2) Get two mixing bowls. Fill one with plain yogurt, and the other with macaroni and cheese at room temperature. Place a wooden spoon in each. Then, remove the chain from your front chainrings and spin your crank. Next, stir each bowl with the wooden spoon. Which bowl does your crank most feel like when turned? If it feels more like the bowl filled with plain yogurt, then it's got anywhere from tens to trillions of seconds to go. If it feels more like the bowl of mac and cheese, consider replacement.

3) It can. Really, are you honestly this obsessed with bottom brackets?

4) No, I don't. Who cares? Yes, you would use a torque wrench for that--if you're a gigantic dork. I mean, using a torque wrench on the actual cups is one thing, but for the preload?!? Do you use a torque wrench to turn off your faucet, or to flush your toilet, or to replace the lid on your half-drunk Snapple? Take a risk!!! How wrong can you really go here?

5) Are you really obsessed to the point that you're ready to give money to Phil Wood? Patronizing Phil Wood is like going to an expensive therapist--this is an entire company based on assuaging the anal and neurotic. Take any normal, properly-funcioning component, like your bottom bracket. Even though it's perfectly fine and more or less incapable of failing catastrophically, you're checking it every day, writing letters to VeloNews, and waiting for it to fail like some kind of nutcase hunkering in a basement bracing yourself for a hurricane that's never going to come. Well, thank goodness for you there's Phil. What they do is make essentially the same exact thing you already have but charge you about three times as much for it because it has a special oil in it. (Or, they make some kind of "overhaul kit" for what you already have that essentially replaces the internals with the same thing. It’s like getting a heart transplant you don’t need.) That way, you can relax, knowing you paid for the "best." So, yeah, if you can't sleep at night due to the fear that your bottom bracket might explode in the night and take you with it, by all means, buy the Phil Wood thing.

--RTMS


Regarding rolling resistance of clinchers v. tubulars discussed in a prior column:

Dear Lennard,

I suggest you look at biketechreview.com. The range of the Coefficient of Rolling Resistance (Crr) for tires in the test, performed on a PVC drum, are similar to the range of Crr for clinchers and tubulars in the Chester Kyle study, published in Bicycling, May 1985. The Kyle study was done on smooth asphalt and low speed trike.

It is obvious that the steel drum used in the Tour magazine study magnifies the differences between tires, the question is how much. Tubulars do not perform well on a steel drum because of the small contact area and the resultant squirming or glue compression. The difference on the road is minimal. In a test done by Triathlon magazine (September 2006), the same six sewups, eight clinchers were tested on both a concrete indoor track and a steel drum. After adjusting for tire load and speed, the range of variability (defined in watts) for the six sewups on the drum was 2.24 times higher (my calculation) than on concrete. For clinchers the range of variability was 1.76 times.

Bottom Line: "Rolling resistance is very close on smooth road surfaces between clinchers and tubulars. Individual tires of either group may have better or worse rolling resistance".

Terry

Hi, Terry. Sorry, Lennard stepped out to enter a Peter Coyote look-alike contest, but allow me to help. Firstly, I couldn’t and didn’t read that. Secondly, are you still seriously confused about the difference between tubulars and clinchers? One involves glue, one doesn't. Take your pick. The real difference is in the rims, not the tires. Tubular rims and clincher rims have different weight and performance characteristics. If you want to use tubular rims, use tubular tires. If you want to use clincher rims, use clincher tires. If you're unsure, use one tubular wheel and one clincher wheel. That way you can't lose. Come on, do you decide between a sports car and a speedboat by comparing the ergonomics of the steering wheels?

--RTMS

Regarding orthotic construction from a previous column, I received some feedback about different approaches:

Dear Lennard,

I am a podiatrist and the pedorthotist's response to proper casting technique for custom orthotics is off-base.

Semi-weight-bearing casting defeats the purpose of creating a properly supportive device. It's difficult to be consistent between patients when utilizing this technique and one should simply use a heat moldable device if this approach is to be used. Yes, the foot compresses and the "arch" lowers and if done properly a non-weight-bearing casting simulating weight bearing by slight loading of the foot in its "neutral" position is the correct way to cast a patient.

Instructions can be given for "posting" of the devices if additional correction is needed. The foam impressions are a quick and easy way to cast but simply does not capture the true simulated semi-weight-bearing that is needed. Also, full-length devices may be appropriate, but if room is needed in the toe box area, a 3/4 cut top cover can be applied to the device without sacrificing any support supplied by the orthotic.

S.C. MurphyDPM

Dear Lennard,

Thanks for addressing the orthotic question. I enjoyed the article and comments by Russel Bollig.

No doubt he has the experience and athletes to stand behind what he says. Because I'm a cyclist and a health provider, I can appreciate the value of orthotics in a cycling shoe. You might say it's the reason I'm still training and racing.

I would, however, like to add a couple comments. I've been making cycling orthotics for a few years now using a neutral, non-weight-bearing cast, which has benefits worthy of mention. In my experience it's not so much about the arch as much as it is a combination of addressing the forefoot/rearfoot relationship, as well as the arch.

The craftsmanship you mentioned required to modify a positive cast's arch to address soft-tissue displacement really isn't a difficult task for an experienced tech, as it involves much less guesswork. I don't have any issues with this step, especially because there are so many benefits to a non-weight-bearing cast.

Because the forefoot/rearfoot is better captured with non-weight-bearing casts, it's much easier to post the forefoot accordingly for the patient's needs. Proper forefoot alignment is what in my experience really makes the difference in proper knee alignment while pedaling, also the basis for Paul Swift's BigMeat wedges.

For a more complete article, please read a recent article I wrote.

Dr. Rich Cimadoro

Sorry, Lennard stepped out to claim his third-place prize in a Peter Coyote look-alike contest. (A bucket of wings from KFC if you're wondering.) Orthotics aside, since you're both doctors, can I ask you guys a question? Just testing out a personal theory. Does either one of you ride a Serotta? I'm guessing at least one of you does. Am I right? Also, theoretically, can the casting techniques you describe be employed in penis gourd fabrication? I was intrigued by the reference to "Big Meat."

--RTMS