Tech letters for January 15, 2002

Edited by John Stevenson

Confounded by carbon fiber? Need to sound off about superlight stuff? Tech letters is the forum for your gear-related questions and opinions. We'll attempt to answer all questions that don't require a PhD in astrophysics or industrial espionage.

Send your emails to Cyclingnews' tech desk

Happy New Year from the tech desk after a longer-than-intended abscence. Letters over the past few weeks have covered cable housing, fit, integrated headsets and lots more uses for old inner tubes.

We've also had a few letters looking for guidance in bike purchases. We're intending to increase the number of bike reviews this year, but it's almost impossible for a publication to answer questions of the 'which $3,000 bike should I buy?' type. All I can do is offer my general rule number one for bike purchase: find a shop where you get on well with the staff, where they're your kind of riders, and follow their advice. Often, it's not what you buy that matters, so much as where you buy it from.

Contents

Cable Housing
Fit & frames
Integrated headsets
Rotor cranks
Crank Brothers Egg Beaters
Disk brakes
Cateye OS 1.0
Inner tube tips

Cable Housing #1

It is imperative to tell the folks when installing new cable and housing NOT to lube the cables prior to running them through the housing. Especially nylon/teflon lined housings. I can't tell you how many riders who do it themselves wind up with drag and friction problems with shifting and or braking.

John J. Koenck

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In that case, why does Shimano supply gear cable outers with a squirt of grease in one end? Some greases are absorbed into the plastic liners of cable housings, but I suspect it's better to use something than nothing at all to prevent the cables themselves from getting rusty. Any tribologists out there?

Cable housing #2

I was looking over your article and would like to ask if there is any information on the brake cable routing for a cyclo-cross bike. My bike has Shimano 600 brake levers and Avid Shorty cantilever brakes. I am particularly interested in the routing of the front brake cable as it is very curved to get into the cable hanger. Any tips here? Thanks for any help.

Chris Bernique

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Cyclo-cross is nonexistent here in Australia, so I have nothing to offer – how do cross fans set up their front brake cables to keep the cable run as large-radiused as possible?

Fit & frames

I like the inner ear theory. That's a good one.

Something nobody talks about when measuring people for custom bikes is the rider's posture. Two people can measure the same and require very different set-ups because one's back is erect and the other is a sloucher. Most people can ride stock frames and tweak their position with stem changes. Before you drop $3,000.00 on a custom frame, watch yourself ride on videotape for an hour on a couple different bikes. Look at your own position and compare it to photo's of pro's. Like what you see? When you "look" the best on a bike it doesn't mean you're going to be comfortable for 5 hours on the road. Be honest on video and slouch if that's how you ride.

Most of us will we need more off the bike exercise to develop core strength rather than micro-building the tubes and angles.

Todd Cullen

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Integrated headsets #1

My GT Rage with 7005 AL just had the sort of head tube failure Cassandra mentions. Luckily, I caught it before it cracked completely, as the handlebar did a week before. At only 165, I never thought I was THAT hard on a frame. Anyway, suffice it to say, head tubes do fail, and lifetime warrantees are only good for the lifetime of the company.

Bill Jensen Illinois, USA

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Integrated headsets #2

I have a C-40 head tube on my desk right now that has the down tube and top tube broken off. Strangely enough, the Star fork appears fine (although I wouldn't want to ride it...). The C-40 has a conventional headset, as well. Anyway, more strength and stiffness in the head tube area is probably be a good thing.

Geoffrey A. Mar Calgary, Alberta, Canada

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Has the head tube itself failed, or the top tube and down tube just behind it? The areas just behind the head tube are the most highly stressed parts of a frame, so maybe thatís where manufacturers need to be looking to add beef, as well as the head tube.

Integrated headsets #3

There is always new, or newly-packaged technology coming down the pipes from the manufacturers. I believe there are two reasons that most manufacturers are going towards integrated headsets: lighter weight (function) and good looks (form).

You have to look at the front end area (head tube/fork/headset) as an integrated unit. By doing away with traditional cups and placing the bearing directly into the machined head tube, you save weight. By using an oversize steer tube, you can use less (or lighter) material, like carbon. The larger the diameter, the stiffer the tube, or something like that. You can save up to one half pound when you compare just the front end and the items listed above!

As far as durability, most new stuff gets put through the ringer with the pro teams. They might get a new bike everyday (perception), or get certain parts overhauled more frequently than us (reality), but it is the best testing ground you can get. Also, no manufacturer would bring it to market without a good bit of testing. At least they shouldn't. They would most likely spend more money on fixing broken pieces or issuing recalls than they ever would make with sales. A good rule is to wait for a year or two. If the technology is legit, then buy it then. There are always techno-geeks(like me) willing to get the latest stuff as soon as it hits the market. Let them be your guinea pig.

Then we get to good looks. You can't argue here, the integrated front end just looks sexier. I know, looks aren't everything, but when was the last you heard someone say, "I know my bike is ugly as sin, but it rides great!" Now, if all you want is a cool looking piece of "technology", then get a frame with carbon seat stays. Don't get me started. Talk about a conspiracy to steal my money...

John Kirchner USA

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Rotor cranks

This is another of the expensive patented items of equipment that is supposed to improve the normal imperfect pedaling style with it's upper and lower dead spots and where maximum pressure can only be applied at 3 o'clock approx.

The Rotor device speeds up the crank on its return to the upper dead spot area and slows it down in the power zone. But you do not need new equipment to perfect your pedaling technique, what you need is to completely change your pedaling style. By switching to the technique of J Anquetil, you can eliminate all dead spot areas and apply almost continuous maximum chain drive power to the chainwheel throughout it's entire circumference and it's free.

Another big disadvantage with the normal pedaling style is that it is the main cause of all chronic cycling related lower back pain, by placing all necessary strain in the lower back, Anquetil's technique hinges all strain in the hips and completely eliminates this torture.

Noel Crowley

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Crank Brothers Egg Beaters

I have raced three sandy & muddy Seattle Metro series races in the pedals, & they were great!!

Treat them like Times, mount the cleat where your time cleats were, no problems. Make sure to cut back your shoes (the cleats are wider than Time cleats) for clean entry in bad conditions. Shave your soles 2mm back from the outward edges of the cleat.

Tim Rutledge Redline

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Disk brakes

I have a very simple question: I have a mountain bike (Raleigh M800) with disk brakes. If I want an extra set of wheels (what I have in mind is having street tires on one set, off-road tires on the other set) and I get a pair of disc-compatible wheels, do I have to also get a set of disks (rotors) to mount to the new wheels? Or are the disks on my current wheels easily and quickly transferred from one wheel to another (easier and quicker, that is to say, than changing tires)?

Eric Snider Toledo, OH

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I haven't tried this, but I'd imagine it would be a major pain to swap the discs over every time you change wheels, and it's asking for trouble to mess frequently with a safety-critical part of the bike. The rotors on my discs are held in place with six Torx screws per hub, so you're looking at undoing and tightening twelve screws every time. Far better to have rotors mounted on both pairs of wheels.

You may also want identical hubs on both pairs of wheels. Different hubs can put the rotor in slightly different places with respect to the brake, so using identical hubs will make the set-up easier and avoid having to mess around with shims to get the rotors in exactly the same positions.

Cateye OS 1.0

One problem seems to be if you don't use it for a couple of weeks it needs to have a hard reset (I was ill and I was using the other bike okay?). Happened twice.

Paul Stratford UK

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Our OS 1.0 sample went unused for longer than I care to mention over Christmas and the New Year and worked fine when the time came to use it. Its only quirk was that it wished me a Happy New Year the first time I turned it on in January!

Inner tube tips #1

One of my favorites that is nearly invisible (a plus for the fashion conscious cyclist) is to use recycled tubes to silence a rattle-prone frame pump and to protect the frame/secure the pump.

1) Ending rattles: cut a 1 inch section of tube (a ring) and pull it over the pump handle, down to the end of the handle where it overlaps the pump body. Fold a little bit of the tube so that it goes inside the handle, while still covering the outside (make a sandwich- tube-handle-tube). This will keep the handle from banging against the pump body and also dampens the spring in the handle.

2) Protect frame and secure the pump: Place a piece of tube on the end of the pump that meets the frame (the end without a peg hole). My old pump has two mounting brackets the meet the frame. I put one end of the tube over one, the other end over the other one, then put the pump on the bike. The rubber grips better than the plastic and keeps the pump from sliding down the head tube.

A bonus third idea: stick your patch kit inside a short section of tube and stop worrying about losing your glue, money, etc. What a fashionable money clip - and it has a story to go with it! Perfect for any hot club...

Randy Hermann

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Inner tube tips #2

I have large hands and like a thicker grip on my road bar. So, I take an old tube, split it lengthwise twice, actually cutting it into two long, narrow strips. Then, I wrap the bare bar with this to get a base thickness where I want the bar thicker (i.e. drops and top of bar to hoods). Then, I overwrap this with my cork or foam color tape.

Gives a thick grip with good cushion, and it is free. Don't like it? You're not out much!

Jimbo

Austin, Texas

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Inner tube tips #3

For protecting the chainstay I use some of my children's clear film that they use for covering their textbooks. It works a treat, is clear, cheap, can be replaced many time if required, and is self adhesive on one side.

I also use small pieces to put under the cable casings typically around the head tube which have an annoying habit of slowly rubing off the paint as they are stretched across as the handlebars are moved.

Doug St George
N orth Sydney, Australia

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Inner tube tips #4

I accidentally cut my band to my rollers during a move, so I put an inner tube on in a temporary replacement. I first had to remove the valve - a simple tug took care of that. I have been riding the replacement for three years, with little performance difference (minor slippage).

Clint

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Inner tube tips #5

As a keen Mountain biker in a wet climate here are some more tips for Cycling News readers.

(1) Headset protection. The bottom headset bearings are very vulnerable to damage from water and mud getting past the seals. How often have you seen that watery brown gravy where grease used to be! When you have your front forks out of the frame, take the opportunity to protect them by cutting a 50mm length of an MTB diameter inner tube. Push this "sock" up over the fixed cup in the bottom of the headtube and replace the forks (with cleaned, greased bearings). Now pull the bottom of the sock down so that the bearing gap is covered. This works well and - in common with the chainstay protector idea from ōyvind Aas - is similar to a commercial (Lizard Skin) product but lots cheaper. Better quality headsets help of course, I can recommend the WTB "Greaseguard" headsets as quality is high and maintenance is so easy and effective. Or - if money is no object - simply buy Chris King, fit and forget.

(2) Chainsuck protection. Simply extend the chainstay inner tube cover forward to cover the whole chainstay and help protect it from chain impact damage.

(3) Trail tools. Use lengths of road diameter inner tube to contain your trail tools. Collect your tyre levers, allen keys, chaintool etc. together and cut a length of inner tube 30mm longer than the longest tool. Glue one end of the tube shut with superglue and then push your tools inside. This will protect your tools, keep them together stop them rattling and wearing holes in your jersey pocket or seatpack.

(4) Pump grip. Use 150mm length of inner tube of a diameter smaller than your pump body and push over the bottom of the pump using soapy water as lube if necessary. This gives a really good grippy surface which is really useful in the wet and mud. Oh, and never, ever, attach a pump to a mountain bike when serious off-roading is on the menu - carry them in your bum bag, back pack or back pocket.

Happy pedalling!

Robin B. Cooney
Ulverston, Cumbria, UK

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Inner tube tips #6

I use an old road tube that I cut in half to secure my icebag when I need to ice an injury. You just wrap the inner tube around the ice bag and the injury a few times, pulling as tight as necessary to keep the ice from moving. Then you can tuck the tube under itself to secure the loose end.

Reed Bartlett
Redlands, CA

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