JIM LANGLEY REPLIES: First, apply a penetrating liquid. I believe your frame has aluminum threading in the bottom bracket and that your BB cups also are aluminum.
If so, try dripping a good dose of ammonia between the cups and frame. If you’re lucky, this will break the bond because ammonia can cut through aluminum oxidation. To help it penetrate, tap gently on the bottom-bracket cups to make the parts vibrate and draw the ammonia into the threads.
Penetration could take several days. Add more ammonia regularly, tap and apply pressure with the bottom-bracket remover.
If this doesn’t do the trick, you could also try heating the parts with a propane torch. But you have to be very careful not to apply heat anywhere it could damage the frame, decals or paint.
To protect the frame, wrap it in wet towels. Heat only the Chorus bottom bracket. This assumes that you don’t mind the probability of ruining any rubber/nylon seals inside the BB.
Heating the bottom bracket this way will cause the cups to expand slightly. Then they’ll contract as they cool. This should loosen the bond and allow you to remove the cups.
When you install the new bottom bracket, apply an anti-seize compound to the threads to prevent fussing over fusing ever again.
Carbon Frame Longevity
DEAR JIM: I have more than 10,000 miles on my carbon-fiber bike. It has never been crashed or dropped. How long can I expect the frame to be safe? Is it true that carbon-fiber frames are only good for about three years? — Bill W.
JIM LANGLEY REPLIES: This is a difficult question to answer definitively. I don’t know of anyone who has kept track of the various brands of carbon frames over a long period.
In this case, “long” is actually quite short. Carbon frames have only been in common use since the mid 1980s when Kestrel came along. The Exxon Graftek was available in the ‘70s but it didn’t catch on. It was the Kestrel 4000 that got the ball rolling. This means carbon frames have had less than 20 years to develop a track record.
Any frame can break — carbon, steel, titanium or aluminum. But they usually break due to some flaw or weakness inherent in the frame’s material at the outset, from a mistake in construction or from abuse or crashing. I’d estimate that I’ve seen about the same number of broken steel, titanium or aluminum frames in the last 15 years as broken carbon frames.
You didn’t mention what brand frame you have. But as long as it’s good quality and was constructed correctly, and considering that it’s in as good a shape as you say, my guess is that it will keep going long past three years.
Ergo-Compatible Cantilevers
DEAR JIM: I’m thinking about having a custom frame made with S&S couplings, set up kind of like a ‘cross bike to be used for commuting, light touring and road riding. I would like to use cantilever brakes so I’ll have clearance for tires up to 32C. I’ve heard about a company called Strangecycles that makes a canti that’s compatible with Ergopower brake levers. Do you have any experience with these brakes? — Mal K.
JIM LANGLEY REPLIES: I hadn’t heard of the Strange Brake, but it was fairly easy to find with a Google search. I followed a link to it at the Peter White Cycles website.
Peter White is a bike guru in New Hampshire. He has very good things to say about the brake. It sounds like it should work nicely on your custom bike with Ergopower levers.
Carbon Fork Choices
DEAR JIM: I’m trying to decide between a Reynolds Ouzo Pro fork and a Look HSC-4. Which do you think is better? — Art M.
JIM LANGLEY REPLIES: I’ve ridden a Look HSC fork for the last 5 years and like it a lot. It’s incredibly light, very smooth and handles nicely. While I haven’t ridden a Reynolds fork, I would expect it to be stiffer and not as smooth as the HSC. I say this because of the Reynolds’ larger-diameter blades, its crown construction and its beefy attachment to the steerer tube (inside where you can’t see).
I weigh 175 pounds and like a “soft” racing bike, so I like the Look. If you’re heavier or ride hard or sprint hard, you might prefer a stiffer fork.
It’s important to match any new fork with the one you’re replacing to make sure you retain the same steering geometry. This is assuming there’s nothing wrong with the way your bike handles now.
Here are 2 technical pages from a friend, Damon Rinard, that give tips on getting the right fork and how different types flex: Fork Lengths, Fork Deflection.
Also, check over at RoadBikeReview for user feedback on a number of forks, including the 2 you are considering.
Finally, you might post a message in Roadie Rap asking other RBR members what they recommend. Be sure to describe how much you weigh, how you ride and which bike and fork you have now.
Repair Stand Damage to Frame Tubes
DEAR JIM: My garage is home to carbon, aluminum and titanium bikes. Is it your experience that I should not be leaving them clamped in my Park repair stands? (I have a repair stand for each bike.) The clamp jaws are set to the lowest tension setting. — Dennis P.
JIM LANGLEY REPLIES: I don’t see any problem with this as long as you’re clamping onto something that can’t be affected by the jaws. That is, if the bikes are being held by their seatpost, you don’t need to worry.
When you could have trouble is if you’re clamping a frame tube. Bicycle tubing can handle gentle pressure from a repair stand. However, avoid clamping where there is also a decal or sticker. They can easily be damaged from direct pressure or if the bike rotates in the clamp. And if the clamp jaws have any dirt or debris embedded in them, as happens over time, it can scratch the paint.
Putting a rag in the jaws doesn’t offer protection. In fact, I’ve seen repair stands dent tubing when the cloth bunches and creates a wrinkle or fold. That’s how thin and delicate tubing has become.
If there is enough seatpost exposed, clamp there. If not, clamp cleanly and gently. Or don’t clamp at all if you’re using a stand merely to hold a bike upright and out of the way. Simply hook the nose of the saddle over the extended clamp arm and let the bike hang.
How to Widen a Rear Triangle
DEAR JIM: I have a vintage 1983 Holdsworth from England. It’s a high-end steel touring bike. It may not be as light as today’s touring bikes, but the steel makes it so smooth. However, after riding my Cannondale R1000, it is very difficult to get back on. The original components were awful to start with, and now I’ve become dependent on STI shifters.
I’ve inquired about updating the components, but the answer is always that the frame’s rear triangle would need to be widened in order to install a 9-speed wheel. I’m told that this would be very expensive. Your advice would be greatly appreciated. — Jim A.
JIM LANGLEY REPLIES: Actually, you might not need to do anything to your frame to get modern equipment to work.
Sometimes the rear-triangle spacing is already a bit on the wide side. Right now, the standard for 9- and 10-speed drivetrains is 130 mm. When your bike was built, it was 125-127 mm. That’s not much difference, so in many cases, a modern wheel will slip into an ’80s rear end. This is easy enough to test by trying to put a friend’s wheel in your bike.
If it’s too wide, you would need to have the rear triangle realigned. This is an easy job that a shop should charge no more than 30 minutes labor for. That should run you about $30, max. Or, you could do it yourself without too much difficulty if you’re just a little mechanically inclined. Here’s how:
1. Elevate your bike. Put it in a repair stand or similar support, or use your car’s rear-mount bike rac. Remove the rear wheel.
2. Check the centering. Tie the end of a 7-foot length of stout-but-thin thread to the right rear dropout. Run the thread around the bike’s head tube and back to the left rear dropout. Pull the thread taut and tie it to the same point on the left dropout as on the right. Now you have an excellent reference for your rear triangle adjustments. By measuring from the thread to the seat tube on each side, you can compare the distances to determine if the rear triangle is centered.
3. Measure the spread. Check the distance between the dropouts (inside face to inside face). This is the 125 – to 130-mm distance I mentioned. If it should measure 120 mm, you’ll need to add 5 mm to each side (assuming that the distance from the thread to the seat tube is equal on both sides).
4. Spread the rear triangle. Stand behind the bike, grab the dropouts identically on each side (one hand on each dropout) and pull apart evenly. On most steel bikes, a person of average strength can spread the frame this way. Don’t pull too hard. Use gentle pressure and recheck the dropout-to-dropout measurement. This way you can determine how much force is required to spread the frame. It’s usually less than expected, so go easy until you reach 130 mm.
5. Recheck centering. The goal is to end up with equal thread measurements to the seat tube, too. You might get lucky and nail it on the first try. If not, don’t worry, it’s not too hard to push on one side of the rear triangle to move it a bit one way or the other. If the bike keeps moving, have a friend hold it while you fine-tune things.
That’s it. Once your frame is set to modern spacing, you should be able to upgrade it as you want. A shop mechanic, by the way, would probably use different tools to do this job.
Racking a Carbon Seatpost
DEAR JIM: I received a Giant TCR as a 40th birthday gift. I’m getting ready to take it on my first multiday bike tour. Prior to getting the bike I bought a rear rack that attaches to the seatpost, which on the Giant is carbon fiber. I was told by a shop mechanic that I shouldn’t use the rack because it will crush the seatpost. But a different mechanic says there shouldn’t be a problem. After all, he reasons, the seatpost is held in place by a clamp that obviously does not harm it. Not being technically savvy, I don’t know whom to believe. Thanks for any light you can shine on the situation. — Juli M.
JIM LANGLEY REPLIES: Nice bike, Juli! I’m afraid I can’t be 100% positive about my answer because you didn’t specify which brand/model of seatpost and rack you have. However, I would expect the combo to work fine. The exception would be if the manufacturer of either part has done testing and learned that they’re incompatible. If so, you’d probably see a warning.
The shop where you purchased your bike (or any Giant dealer) should know if the TCR’s seatpost isn’t designed for use with a seatpost rack. I checked for an advisory on Giant’s website but didn’t find anything.
I do have one concern, though. Carbon is “notch sensitive,” meaning that a scratch or gouge can cause it to break. So the clamp on the trunk rack must be smooth and not dig into the seatpost even a little. Usually, manufacturers design clamps to be smooth and free of burrs. You can inspect it to make sure. You can also protect the post with electrical tape.
The second mechanic is right: It’s not easy to crush a seatpost. It’s held by the seat clamp much like a rack would grip it. And stems clamp carbon forks without problems. I suspect that what you want to do will work fine, but double-check with a Giant dealer to be sure.
Slipping Handlebar
DEAR JIM: I recently switched to the FSA K-Wing carbon handlebar and a FSA OS 115 stem. I love the ride quality of the combo, but if I hit any sort of a bump on descents the bar rotates down.
On my last ride I hit a particularly nasty bump that was hidden by a shadow, and the bar changed position so dramatically that I almost went down.
I’ve had the bolts checked and they are torqued to spec. Can I make them a little tighter, or is there anything I can do to alleviate this problem? I worry about cracking my brand new handlebar. — Jason G.
JIM LANGLEY REPLIES: It sounds like the bolts may not have been lubricated enough, if at all. This would make the torque numbers read high when in reality the bolts should be tighter.
According to FSA, you should apply Ti-Prep to the threads and bolt heads (the surface that rests on the faceplate), and then evenly tighten the bolts in an X pattern to the recommended torque setting. You can find an instruction sheet on the FSA website.
Of course, be certain that no grease has gotten on the clamping surfaces of the handlebar or stem.
Chrome Plating
DEAR JIM: I’ve heard bad comments from riders about chrome on a steel frame — everything from it being heavy to adversely affecting the metallurgy of the tubes.
Can you set me straight? I’m in the process of acquiring a new custom steel bike and I like the look of chrome-plated dropouts and right chainstays. I plan to race the bike, so if plating would produce adverse effects I will avoid it. — Carl C.
JIM LANGLEY REPLIES I think chrome looks nice, and it’s practical, too, because it won’t chip or scratch easily the way paint can. So, I would not hesitate to buy a bike with chrome or even have one plated.
The catch is that the plating must be done properly or it will not last. Check with the manufacturer or retailer to see what they can tell you about the bike you’re considering and the quality of the finish. See if you can get in touch with owners of plated frames from the same company.
If it’s a custom frame, be sure the paint/chroming is done by a professional bicycle finisher who knows his stuff. One of the best I’m aware of is Joe Bell. He’s famous for painting Richard Sachs frames and restoring classic bikes, such as Masi and Cinelli. Check Joe’s website.
Frame painters generally don’t do the plating. But because they handle complete repaints for customers, they work with platers they trust to do a quality job on thin-wall bicycle tubing.
If plating is done poorly, the chemicals used in the process can remain in the frame causing a type of deterioration called hydrogen embrittlement. This results in accelerated rusting inside the frame. I experienced this on a road frame I built and had plated by a motorcycle shop. A couple of years later, the seat tube collapsed when I put the bike in a repair stand. I found that all tubes were cancerous with rust, so I had to throw the frame away.
But as long as the frame is plated properly, there’s no reason the job won’t last as long as you do.
You should protect steel frames on the inside with a rust preventive called Frame Saver (scroll to the bottom when this page opens to see Frame Saver). And you should keep the outside of the frame waxed.
As long as you do these things, your chromed frame will look great forever, just like my original-condition 1974 Schwinn Paramount.
Bottom Bracket Codes
DEAR JIM:How can I identify which threading, Italian or British (ITA or BSC), is in the bottom bracket of my bike? On the drive-side facing it says: SHIMANO VI JAPAN VIA 36 x 24T 70. What’s it mean? I don’t see any indication of thread type. — Peter S.
JIM LANGLEY REPLIES:It’s in code, Peter! The numbers on the facing tell you what threading the bottom bracket has.
Several types of BB threading have been used over the years. Today, the most common are English and Italian. There’s also French and Swiss.
Yours is 36 x 24, which stands for 36-mm diameter by 24 threads per inch. That’s Italian. More common, at least in the U.S., is 1.370 inches by 24 threads per inch. That’s English (aka British). Rarer is French or Swiss. These are marked 35 x P1, meaning 35-mm diameter by 1 thread per mm.
On an Italian bottom bracket, both cups are turned clockwise to tighten and counter-clockwise to loosen and remove. On an English BB, the right cup (chainring side) has backward threads. You would turn it counterclockwise to tighten.
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