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Technical FAQ with Lennard Zinn: LED lights, trainers and saddle adjustments

  • By Lennard Zinn
  • Published Nov. 20, 2002
  • Updated Oct. 12, 2010 at 8:55 PM EDT

VeloNews technical writer Lennard Zinn is a frame builder, a formerU.S. national team rider and author of several books on bikes and bikemaintenance. Zinn’s VeloNews.com column is devoted to addressing readers’technical questions about bikes, their care and feeding and how we as riderscan use them as comfortably and efficiently as possible. Readers can sendbrief technical questions directly toZinn. Zinn’s column appears regularly on VeloNews.com.


Question:
It would seem like the ultimate night riding light would be an L.E.D.light for light weight and efficiency. Has there been anyone working onbringing this out or is the technology difficult for lights bigger thana flashlight? –Charles

Answer:
I got very interested in this question, and I did a bit of research. A recent article in The Economist predicts that all of our interior lights will be L.E.D.s. In the bike industry, the people at Cateye seems to be the furthest into this technology. At Interbike, they even used battery-powered L.E.D.s to illuminate the displays in their booth! The EL300 light with four L.E.D.s really throws some light, although it is not even remotely comparable to a high-powered light like a NiteRider. It is fine for road riding at moderate speed, but you can’t ride dark trails with it any faster than at a crawl.

On the other hand, it is way brighter than Cateye’s best L.E.D. light of only a year ago, so we can expect itto continue to improve rapidly. The most amazing thing about it is that you get about 12 times the battery life of a light putting out comparable illumination.

–Lennard

And two responses from Cateye:
We have three new L.E.D. lights out…the EL110, EL200, and EL300.All run on 4 AA batteries with about 100 hours run time. All feature our new Opticube lens technology which focuses the light for better pinpoint brightness.
EL110: 1 L.E.D. light for focused pinpoint brightness. Suggested retail – $19.00
EL200: 3 L.E.D.’s with about 110 candlepower, features a flashing mode and constant mode, suggested retail – $25.00
EL300: 5 L.E.D.’s, most powerful of the L.E.D. series form Cat Eye with about 400 candlepower, suggested retail – $35.00
For more info: www.cateye.com
–Patrick Reedy
Cat Eye Service and Research Center

And:
Actually our most popular light right now is the LD300. This is… Aaah… Bigger than a flashlight…. But it is not what we would call HIGH Powered.This technology is progressing but there are still considerable performance limitations still…when it comes to total light output. The EL300 is roughly equal in light output (measured in candle power) as that of the HL500 (the first halogen bike light ever!) so you can see…There is hope from Cat Eye that we will get there some day! The big difference between the HL500 and the EL300 is the L.E.D. light has 100 hours run time compared to 8 for the halogen light!!!
–Thomas Prehn
Cat Eye Service and Research Center

Question:
I am new to road biking and have found I really like it. I would like to get a trainer. It sounds like the magnetic resistance is the way to go. I would like to be able to change the resistance while riding. Do Ihave to spend $400 to do this or get a durable solid stand? Any recommendations?–Kelly

Answer (from Andrew Juskaitis, our in-house trainerexpert after his unfortunate broken leg this fall):
First off, if you’ve found yourself falling for the sport of road riding, I’d highly recommend staying away from a trainer–there’s no fasterway to learn to hate the sport then spending countless hours pedaling away in your basement watching Ren and Stimpy re-runs. If you live in terrible weather, or you just can’t make the time before or after work to ride outside, a trainer is a viable way to improve/maintain your riding fitness.

If you’re in the market for a new trainer, keep in mind there are three types of resistance–wind, magnetic, and fluid. Windtrainers were the first on the market, but are generally loud and don’tprovide a realistic road feel (although they do help keep you cool). Magnetic trainers were next on the market and can provide good, realistic resistance workouts. Fluid trainers are the latest technology and offer the extremely quiet, realistic road workouts (although some leak their heated, expanded fluid). You certainly don’t have to spend $400 on a trainer.

My two favorite are the CycleOps Magneto ($229) and the Kinetic Fluid Trainer($340). Both are great options–but do yourself a favor and try and get outside as much as possible–you’ll be sure to a long and happy relationship with your new-found love of cycling. -

-Andrew

P.S. Check out Andrew’s review of stationary trainers in the October 21 (2002) issue of VeloNews

–Lennard

Question:
My seat rails are as far forward as they can go on my Campy Record seat post. This post has quite a bit of setback and I’m wondering if I should get a different post so the attachment is centered on the rails? I’ve read that the rails should be centered so the seat flexes appropriately. My fit seems good, it is a Flite standard saddle and a 59cm Litespeed Classic. Thanks, and you have a great road bike maintenance book!

–Dave

Answer:
Try something like a Thomson seatpost then, which has no setback (the straight one, not the bent “road” post). And yes, the saddle does work better if it is not clamped at one of the extremes of the rails, particularly the rear one. If it pushed far forward, it becomes very flexy in the nose without offering suspension in back, since the rails generally come up almost vertically in back from the bend.

–Lennard

Question:
Is it possible to change a threaded headset to a threadless system?

–Dana

Answer:
Yes. Get a new fork with an unthreaded steerer of the same diameter as your old one, as well as a new threadless headset of that diameter aswell.

–Lennard

Question:
I am running a chorus gruppo 53-39 & 12-25 on a Serotta road bike. In the past, I’ve used the Campy 10 speed chain but repairing this chain is very difficult out on the road. Would the magic link chain or any other chain work well with the Campy setup? With the Campy 8, I was able to usea chain tool and do a road repair.

–Lanny

Answer:
I have used Dura-Ace and SRAM chains on my Record 10 with no problems. Also, the new Campy 10 chain comes with long break-off pins like a Shimano.

–Lennard

Question:
(Editor’s note: This question is from the famous Aussie, Skippi, who rides every stage of many of the major stage races — the Tour, Giro, etc. — a couple of hours ahead of the peloton) After five seasons with five Tours de France, four Giri d’Italia, four times at La Vuelta, four at Paris-Nice and a bunch of other tours, I now have stripped the frame you have seen so often. As you wrote in the 2001 Giro “Skip the Driving” article, the seat post welded into the frame. At first I tried heating up the frame to no avail. Then, having sawed off the top part, I tried to drill out most of the residue. Then with a cold chisel I tried to dislodge the remainder. So I am nearly at a stage where the frame is ready for a respray.

My question is: what damage will the heating of the frame have done and are the small bumps in the tubing from the cold chisel a problem when hammered flat?

The reason I wish to keep the frame is because it has given over 80,000 km and could be used for the Taxc trainer if not as a spare bike. What is your view on the matter? –Skippi

Answer:
As that is a steel frame and you did not melt the brazing material in the process of heating, then you have probably not damaged it by the heating. The cold chisel gouges could be more of a problem, but if they are within the area supported by the lug, then they are probably okay as well.

–Lennard

Question:
I just bought your third edition maintenance book. Hey, I’m glad to see you put Paul Morningstar’s info in there. I bought your performance book last year, when we exchanged some emails, while you were in Italy. I have a question about brake boosters for V-brakes, which was not addressed in either of the books – at what distance from the brake arms should a booster be mounted? Some kits come with lots of spacers and washers, others don’t. Is farther or closer better for preventing flex? Also, is the use of a really long screw preferable for this installation (as opposed to a screw that grips a good amount of thread but does not go all the way to the bottom of the brake boss)?

–Liviu

Answer:
It really should not matter how far away from the brake the booster sits, nor should the bolt length, as long as it engages a couple centimeters of thread. As long as it is reasonably close, there should not be any flexof the bosses or the bolts between the fixed points at the frame and the booster.
Thanks for your kind comments,

–Lennard
Question:
I’m trying to pull my Ultegra cranks from the splined spindle bottom bracket. The problem is that the retaining ring that retaining bolt is supposed to push against to remove the cranks is spinning along with thebolt when I try to loosen it. The new bolt/ring pairs that I got with Dura-ace crankset seem to move against each other very smoothly while the ones in my current crankset do not. Perhaps they are damaged in some way? Can you let me know what the easiest and cheapest way to remove the cranks is? I don’t mind sacrificing the current bottom bracket and/or crankset in order to remove them. I thought about just loosening the retaining bolts a little bit and going for a ride to wear out the spline/crank interface slightly, but I’m not sure if this will work. Does anyone make a crankpuller for this kind of situation? — Eric

Answer:
The cheapest thing is to use a pin tool to hold the ring while you unscrew the bolt with an 8mm hex key. You need one that will hold into the little holes well and still give you good leverage. There are also inexpensive crank pullers available now for splined bottom brackets.
–Lennard

And, from Park Tool:
Try Park’s CCP-4. See http://www.parktool.com/tools/CCP_4.shtml
This fits the ISIS Drive and the Octalink system that do not usea one-key release system. On a related note, the retaining-rings (“dustcaps”) on the one-key system seem to be on the loose side, and fall out,as noted below. The SPA-2 is a good tool for these, as it gives plentyof leverage. See http://www.parktool.com/tools/SPA_2BIG.shtml
–Calvin Jones
Park Tool


VeloNews technical writer Lennard Zinn is a frame builder, a formerU.S. national team rider and author of several books including the pairof successful maintenance guides “Zinn& the Art of Mountain Bike Maintenance” and “Zinn& the Art of Road Bike Maintenance.”

FILED UNDER: Bikes and Tech 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.

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