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Tech letters for June 19, 2003 - Answers #2

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.

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Answers and reponses to questions raised last week.

Answers #1

Kinky tubulars
New Ksyriums
OCLV creaks
Campagnolo Pro-fit pedals
The best road bike
Train on tubulars or clinchers?
Which saddle?

Kinky tubulars #1

This may seem obvious, but here goes, anyway: is the bump near the valve? Sometimes repeated downhill braking will heat the glue, and the tire will shift circumferentially around the rim from braking forces; this combo may result in the valve being twisted out of alignment in the valve hole and this may become pronounced enough to distort the tire at the valve, resulting in a bump. If not too bad, and on the front wheel, simply reverse the skewer and computer magnet and ride the wheel in the reverse position/direction for as long as it takes to ``brake`` the tire back into its proper position. If more pronounced, re-glue before the valve tears from the tire.

Otherwise, your problem may in fact stem from a weakening or separation of an underlying and invisible ply in the carcass, or from the stitching coming apart under the base tape. This can result from a manufacturing defect or perhaps from overinflation. Generally, nylon/synthetic carcasses tolerate overinflation better than cotton does.

Pierre C. Lacoste
Montreal
Wednesday, June 11, 2003

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Kinky tubulars #2

I would check to make sure the tire is glued on properly. If a tubular rotates, the force is stopped at the valve stem and then sent back through the tire. This often leaves a hump in the tire. Sometimes it is permanent but other times it will be relieved when you remount the tire. You can usually see some evidence of this by looking at the rim strip. If you see straight black lines towards the outside of the tape, it means the tire has been moving on the rim. This is common on wide cyclocross tires mounted on normal road rims. You just have to be extra careful when gluing the tires on.

Jim Cushing-murray
Thursday, June 12, 2003

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kinky tubulars #3

Greg, Simple one - your tubular shifted along the rim under load, and due to a lack of grip or contact of the glued surfaces. Since the tire was fairly new, there was probably not enough glue on the tire [they tend to soak it in when new]. Look carefully at your valve stem - is it cocked to one side? Or is there another area of the tubular that has "come up"?

I would suggest to remove the tubular, reapply glue to both surfaces and allow it to "set up", then mount the tire and let sit overnight after inflation. That should solve your problem- at least it did for me with similar symptoms.

Michael Stechow
Wednesday, June 11, 2003

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Kinky tubulars #4

I have had the same experience several times over the past 40 or so years of riding tubulars, so I don't think this is a particularly rare occurrence. In the old days, it seemed to be more likely to occur with cheap training tubulars. In recent years I have had this happen with Vittoria CX and Continental tubulars, both quality products and much superior to the tubulars of yesterday. I dissected a couple of the dog-legged (i.e.: kinky as a dog's hind leg!) tubulars, and found that the outer of the two layers of fabric in the main carcass had split in a perfectly straight line for several centimetres, right under the edge of the puncture-resisting strip under the tread. However, I am pretty certain that the old training tubulars had no such puncture-resisting strip, but still occasionally failed in the same way.

No-one I have asked about this has ever been able to explain the exact failure mechanism at work here. I know that I neither over- nor under-inflate my tubulars, I am a lightweight, smooth rider, and I typically get 4,000 km or more out of today's quality tubulars. Maybe the occasional dog-leg failure is just one of those things with tubular tires.

Peter Heppleston
Edmonton, Alberta
Wednesday, June 11, 2003

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New Ksyriums #1

Oops. Should have looked a little more? Count on Cyclingnews to bring it to you. There's better pictures located at here.

Michael B. Seiler
Wednesday, June 11, 2003

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New Ksyriums #2

I work for a bike store in Montreal. The wheel will be available at the start of the tour. The wheel will be silver with one yellow spoke. As for the weightly sales rep from mavic told me is the same weight as the regular Ksyrium SSL

Dianne Markham
Canada
Friday, June 13, 2003

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OCLV creaks #1

I had what I thought was a creaky OCLV frame. I was convinced it was the bottom bracket. With everything out except the wheels, I could make it creak by applying pressure to the BB area.

It turned out the King headset was slightly loose, and was creaking. Noise travels well down the tubes, so it could be that your creak isn't coming from where you think it is either. You can't be sure the creak isn't one of the other parts unless they are all off the frame and it still creaks.

The bad news is that if it does, I don't see how it can be anything other than the bonding.

Leon Gierat
Wednesday, June 11, 2003 (BST)

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OCLV creaks #2

I own a Trek 5000 carbon-frame bike of the same vintage, a beautiful bike. I have had the same problem for years. The sound is coming from the bottom bracket, though it radiates throughout the frame. The cause is moisture (doesn¹t have to be a matter of riding in the rain). Even riding on a wet road will cause the problem. Moisture gets in from the rear of the seat tube and migrates to the bottom bracket. The bearings are sealed, but the moisture migrates to the threads holding the bearing-axle assembly to the bracket.

The cure is to remove the cranks and bracket, dry off everything, recoat with lithium grease or use Teflon tape. This requires a torque wrench to get the torque pressures about right.

The best preventative is to remove your seat after a wet ride, invert your bike, and let it dry out over night. By the way, I have the same problem with my new Merlin Cielo.

Sherrye Young
Tennessee, USA
Wednesday, June 11, 2003

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OCLV creaks #3

When do you hear the creaking, and where does it seem to come from? In the majority of cases creaking isn't actually coming from the frame; I assume you've already gone through the various items found in the article about noises on our website (www.ChainReaction.com/noises.htm).

As for the frame, I'd check for evidence of serious chain suck, since that can try to chew a hole through the chainstay (which will definitely cause noise if it begins to crack), remove & re-torque the bottom bracket (and, if it's a cartridge style, make sure you lube all the surfaces that make contact with one another), and I'd also inspect the headset as well, since slightly-loose cups or races can make a racket.

Have you brought it into a shop (preferably one that sells a lot of Treks) for diagnosis?

Mike Jacoubowsky
Chain Reaction Bicycles
Redwood City & Los Altos, CA
Thursday, June 12, 2003

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OCLV creaks #4

Regarding your problem with the creaking frame, I had the same problem with my look carbon fibre frame. I solved it by smearing grease into the front and rear dropouts.

Craig Drake
UK
Thursday, June 12, 2003

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OCLV creaks #5

I have ridden OCLV frames for over eight years now. I too have had my share of creak and groans. Because OCLV, or any carbon will resonate a sound quite well, it is often challenging to locate the source. The most common culprits are axles in the dropouts. Any bit of grit or dirt between the axles and the dropout will send quite a noise back up the fork. Use a Teflon based lube to clean that connection point. The other culprit is the Bottom Bracket. The BB's on these bikes can have play. A wise, and often common solution is to use Teflon tape, commonly used for plumbing seals, to wrap the BB threads with. This will stop most creaks.

In general, any loose connection or dirty connection will resonate a nasty sound throughout the bike. Keep it clean and tight, you should have no more problems.

Chuck List
Salt Lake City, UT
Friday, June 13, 2003

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OCLV creaks #6

I have sold a lot of Treks over the years and it sounds, very sadly, like it could be the aluminum bottom bracket sleeve. On a few of the older versions of the frame, the sleeve would become loose and even pull free of the carbon. Granted, we are talking a small number of frames, but it did happen to a few customers of mine and a few other riders that I knew. I wouldn't recommend putting anything into the area, since grease or lubricants (like Tri-Flow) can help to weaken the adhesive holding the sleeve in place. It's probably best to check with your dealer and see if they can confirm, if they haven't already, that the creak is coming from the frame. Maybe, in the end, it would even be a good idea to send it to Trek; they may be able to "re-glue" the bottom bracket sleeve.

Otherwise, I'd suggest making sure you have a little grease on the seatpost and stem where they meet the frame. Those frames are notorious for amplifying small creaks so that you start to go nuts looking for it.

Tim Jackson
San Diego, CA
Wednesday, June 11, 2003

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Campagnolo Pro-fit pedals #1

I have used them for 2+ years. Great METAL not plastic engagement for safety/durability. Good clearance, release, support. My only complaint is the angle the pedal rests at is still tricky to kick over and engage for criterium starts, the pedal weight balance is such that it spins too freely to make a second attempt. No crits no problems.

I used to love the now-discontinued Diadora Powerdrive as it was foolproof to enter.

Howard Hesterberg
Hickory NC USA
Wednesday, June 11, 2003 (PDT)

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Saddles on pave #2

The Fizik Aliante has some nice suspension built in via its hammock-like construction. I've ridden Flanders with this saddle. However, nothing is going to make the going comfortable unless you're riding a huge Enduro bike.

Angus Barber
Wednesday, June 11, 2003

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Saddles on pave #3

I have tried many saddles over the years, but recently have discovered the Fizik Aliante - nothing I have ever ridden has come close to this on comfort. It is pricey but well worth the money. Cyclingnews has reviewed it with the same conclusions.

Oren Peleg
Wednesday, June 11, 2003

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Saddles on pave #4

The pros (or most of them) will use their usual saddle on pave. The reason being that it would probably cause problems if they changed it, different shapes from their well calloused behinds etc. When you really put the hammer down on cobbles you tend to lift slightly anyway so you don't feel the saddle too much. It's the hands that really take a hammering.

Ben Atkins
Brighton, UK
Thursday, June 12, 2003

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The best road bike

In 1973, I bought my Schwinn Paramount from Dennis Stone (Stone's Cyclery, Alameda, Ca.) and he said, "Now, go drop it in a rock pile and scratch it up - so you can really enjoy it." The message - ride it hard everywhere. I did ride it hard, that is.

I have a modern custom now. Yesterday though, I rode the Paramount and stopped by a shop. The owner said, "Riding the Classique?". To which I responded, "It climbs great and descends as good as anything. I still love it." He said, "That's what they're supposed to do." Yup. Modern frame technology is trying to match the handling and ride of the classic 531 frame, while doing it with a 2lb frame and 11 oz fork and they're doing very well at it.

By the way, when test riding a bike, be sure to use the same wheels and tires that you will be purchasing.

John McKain
Bellevue, Wa
Thursday, June 12, 2003

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Train on tubulars or clinchers? #1

Once in a while there are compelling reasons to race on tubies, given that the coolest of race wheels only come in tubular rim versions. However, I cannot imagine anyone training on tubular tyres these days.

Why? Because if you go on a solo ride with three spare tyres and get 4 punctures, you are walking home. Similarly, if you go on a group ride and are the only person with tubulars, if you get one more puncture than you brought tyres, you walk. It used to be the case that everyone would carry at least one tyre spare, so the collective group could get many punctures without anyone walking.

On the other hand, you can carry three or more tubes in the space of one whole tyre, and a pocket full of patches, and get a dozen or more flats and still ride your bike home.

Dr Michael Hanslip
Australia
Wednesday, June 11, 2003

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Train on tubulars or clinchers? #2

The best part about training on tubulars is that you get to use up your old or dubious tires from racing. If you train hard, pay the entry fee, gas money and motel bill, it is madness to race on marginal tires. Training gives them a second life. You will also need some training specific tires. The cheaper Tufos are the only ones I find have the durability you expect from a training tire. With the safety factor of tubulars and the great ride, I wouldn't do it any other way - and neither would my wife.

Richard Heisler
Eureka, CA
Wednesday, June 11, 2003

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Train on tubulars or clinchers? #3

I am from the old school (cyclist from the 70's), so when I reentered cycling in the late 90's I swore I would never ride clinchers. But I have changed my mind. It seems to me to be too expensive to use tubulars for training. Today's clinchers ride very well and are not expensive and easy to fix.

I finally gave up on my tubulars while on a training trip to Arizona. On around a 60 mile training ride, I had flatted twice after already 20 miles( I had taken two spares with me!), so now I was riding on my last hope. Fortunately, the last tire held out.
I would never train on tubulars again on such roads where there is a lot of agressive debris on the shoulder.

Here in Wisconsin, a number of my friends ride tubulars all the time for training. They simply love the ride quality. This is a case of personal preference and if there are hassles or expense, it is simply a personal choice. But we don't have the same flatting problem here in Wisconsin that I experienced in AZ and some of these guys seem to ride the same tires for a very long time and swear that tubulars flat less than clinchers.

My son, who is a competitive racer trains on standard relatively heavy clinchers, but always races on top of the line tubulars.

Bontrager Race Lite wheels for training with heavy duty clinchers.

Bontrager Carbons for racing with Conti comps.

I think this gives him an extra perk on race day.

At the end of the day, whatever turns you on to riding is what you should do!

Dirk
Saturday, June 14, 2003

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Train on tubulars or clinchers? #4

The tyre sealant is a real bonus for those of us who train on tubs. lots of advantages, cheaper, better ride, rims last longer, cheap second hand wheels available (7 & 8 speed anyhow). Spread the word, we need more people on tubs then we can share spare tires if we have to, like in the good old days - when even an average bike cost a couple of months pay... maybe they weren't such good old days, though bikes never seemed to get outdated then.

Dave Moss
Sunday, June 15, 2003

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Train on tubulars or clinchers? #5

Greg, do not use cheap tubulars. They will fail, and usually aren't even close to being round. The roundest, best value for the money, and highest mileage tubulars I have found are Tufos, for sure. They are half the cost of a Conti GP, and are much rounder with no raised section at the valve stem.

The Tufo tubular tape is awesome, I have used it for a year or so with great results, from everything from track, to 28mm. Clement Campione Del Mondos, to 32 mm. Cyclocross tubulars. I have flatted about 5 times with the tape, and I simply peeled off the tape, and put on a new strip, in 5-10 minutes. The key is carrying a pre-stretched spare tubular. Don't bother with the sealant, it's messy and heavy and just masks the problem. Just bring an extra gluing tape with you, and make the permanent repair on the road.

Mike Knudsen
Monday, June 16, 2003

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Train on tubulars or clinchers? #6

I ride tubulars only. I prefer the quality of ride & control in descending, cornering etc. I train on low level tubulars, around $15.00 per tyre and usually get at least 2-3000km out of them. Also being from Canada, I must spend a considerable amount of time during the winter months on a fluid trainer, which eats tyres as anyone out there will attest to. When I race a use high level tubulars - Vittoria Corsa CX - and they are amazing. Most of my friends use clinchers, mostly high level clinchers, and they puncture more frequently than me.

In closing, I can only speak from my experience, if you spend the extra cash, you can usually get more reliability, but as you all know, there is always that rogue nail or piece of glass waiting for your $120.00 tyres. When it comes down to it though, it is all personal preference

Eric McIntyre
Nova Scotia, Canada
Wednesday, June 11, 2003

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Which saddle? #1

Which saddle you choose depends on where you sit. No one but you can determine which saddle is most comfortable. And, unfortunately, it is probably impossible to assess a saddle without riding it on your normal rides.

I have a Selle Italia SLR which is the most comfortable saddle I have ever had. It fits my bones perfectly. I normally do a least one 4 hour plus reasonably hilly ride per weekend. However, other friends of mine who have tried this same saddle hate it and find it very uncomfortable.

Harry Pugh
Wednesday, June 11, 2003

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Which saddle? #2

Definitely the Aliante - far more forgiving. I rode the Tour of Flanders on one this year and my back side was most probably the only part of me that didn't ache afterwards - highly recommended.

Fraser Kennedy
Fleet, UK
Wednesday, June 11, 2003

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Which saddle? #3

I have about 1000 miles on an Aliante and think it is very comfortable. It is similar in shape to the Flite I rode for five years but considerably more comfortable, especially long rides. However it is not 160 or 165 grams unless you remove the scuff guards. Most pictures in catalogs do not have the scuff guards, they weigh about 30 grams and the importer says they will not warranty any tears in the leather if they are removed. Still recommend it highly.

Mick O'Gara
New Hampshire, USA
Wednesday, June 11, 2003

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Which saddle? #4

Great question! This past winter I asked myself the same thing and decided to figure it out once and for all. I proceeded to buy about 10 saddles on Ebay. Everything from an old fashioned appearance of a Rolls to a sleek SLR. After giving each one a good try of a week or two, I found the SLR Trans Am to be the most comfortable for me. At 185 grams it's not the lightest out there, but not the heaviest by any means.

When it comes down to it, it's very much a matter of personal preference. One of my teammates found the Flite to be the best for him, and another the Concor. I suggest trying a few. Your local bike shop will be able to let you know which saddles will feel very similar to others.

The saddle is one thing I buy that I don't take cost into consideration. After all, our butts probably spend more time on that saddle than any other single place.

John Randolph
Wednesday, June 11, 2003

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Which saddle? #5

I've had both on my Cannondale track bike. The Aliante is still on there. It's like sitting on a Harley. Get it.

Stefan Cooper
Maryville, Tenn.
Wednesday, June 11, 2003

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Which saddle? #6

I like my Fizik Aliante very much. It certainly is light, but more important than its weight is its fit. It is the most comfortable saddle I have ever owned, and that makes it worth the price to me. Will it fit you as well? Before you plunk down that kind of serious money you'll want to cozy up to a friend who owns one and find out.

Jonathan Pollard
Juneau, Alaska
Tuesday, June 17, 2003

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Which saddle? #7

I have ridden both the Fizik (riding it on both of my bikes now) and the Selle Italia SLR. In my opinion, there is no question. The Fizik is a FAR more comfortable saddle! I like the padding and the shape.

I have ridden many saddles (Trans Am, Brooks Swift, Flite gel, etc.) and won't give up the Fizik ever again!

Saddles are like women, everyone likes something different but a guy sure is lucky when he finds the right one!

Jeff Hall
USA
Monday, June 16, 2003

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