Saturday, January 2, 2010

Q&A: Old Pedals, What's Upright, Chaindrag, Holy Bars, The Deal On Steel

Q: Hi Jim!
I was directed to your website by someone who works in my local
bike shop. I recently purchased a pair of 1970's vintage Lambert pedals in gold. I was planning on using them on a kind of retro mountain bike commuter build-up. I am using brand-new 2010 Race Face cranks. I bought pedals online, and I was told by the seller that they were 9/16-inch, which is standard mountain bike size. They indeed look to be 9/16, but will not thread into the cranks or into several other older mountain bike cranks I have tried them in.

The threads look to be the same pitch (I think this is the correct term for spacing of threads) when compared to another mountain bike pedal which will screw in. The threads on the Lambert pedals look to be thicker and not as pointed. It seems like they have a`flat' on top. Lambert had their own cranks, and it has been suggested to me they might have cut their own style of thread to be specific to their cranks; or are these threads damaged? Unfortunately I've provided a photo. Any insight you can shed would be appreciated. I'd like to sound intelligent if I need to contact the seller.
Roy

A: Hi Roy,
There were some unusual things about the Lamberts but the pedals should have standard threading (9/16 x 20). The weird one is French but you wouldn’t expect to see that on a Lambert. There is a difference in thread pitch (the angle/shape of the thread) between British and Italian and Japanese 9/16-inch pedal threads but it doesn’t prevent them from going together. It can make screwing them in tougher though.

So, I think the threads are probably slightly different, the pedals being old, the crankset being new. What I would do in the shop if I was troubleshooting this is run a tap through the crank to make sure the threads are in perfect shape. Then I would try the pedals again. If you can get them started, they should go in. Be sure to grease the threads liberally and don’t force them in until you’re positive that the threads are mated well and the pedal is going in straight.

Also, I’m sure you know this but just in case, be absolutely certain to put the right pedal on the drive side and the left pedal on the non drive side, the former gets turned clockwise and the L gets turned counterclockwise. I see people ruin so many pedals and crankarms that I have to mention that. For more tips, you can read all about pedal installation/removal here.

If you don’t have pedal taps a shop should be happy to run them through your cranks to clean up the threads for next to nothing. It only takes about 5 minutes.

Lastly, I don’t want to jinx you but the Lambert bicycles were notoriously poor quality. I would be very careful riding those Lambert pedals. Lambert frames and forks broke, their cranks were as soft as butter and bent simply when you shifted the front derailleur, and there were numerous other problems. Lamberts are interesting history pieces for sure, but in my experience it’s a mistake to depend on them or the Lambert parts. That’s just a caution. Classic Rendezvous has a lot more about Lamberts. (The photo shown is theirs.)

Hope this is helpful,
Jim
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Q: I'm shopping and considering two different road bikes, Jim. One is more upright than the other. What does that mean? Which bike dimensions are the most important?
Thanks,
Steve

A: Boy that’s tricky to answer, Steve, because “upright” can mean a few things and I don’t know which you’re talking about. But, I’ll take an educated guess based on what’s going on in road bike design and say that what you’re probably comparing is a true road-racing bike and an upright version of the same bike, for example Cervelo’s S3 versus their RS (visit www.cervelo.com to compare them if you want).

Basically the former is a true road racing bike because it’s built for every possible competitive edge, no holds barred. This means a low, aero rider position, pretty extreme and best for flexible, fit athletes. This is decidedly not right for an awful lot of people, but still probably the majority of people who go shopping for road racing bikes and want the “best” end up with a bike like this. It’s a little like wanting a dream sports car and ending up in a Formula 1 race car.

Recently some companies are realizing that you can get 99% of the performance of this bike and heck of a lot more fun for the average sport rider if you just make it a little more “upright,” by designing the frame with a taller head tube that raises the bars an inch or so. Sometimes you’ll find a very slightly longer wheelbase. And, on some bikes, like Specialized’s there are even vibration damping elastomer widgets in the fork and stays to eliminate a lot of road shock.

But, essentially it’s a different rider position that’s a touch more upright that makes most people feel far more comfortable so they can enjoy all the excitement of road riding without any of the suffering of the super low aero position – and the best part is that other riders can't tell the difference unless they really, really know their bikes.

Hope this is helpful. Oh, FYI, the other upright is the old use, which was simply talking about how steeply pitched the seat tube and the head tube on the frame was. This affects comfort but is mostly used for dialing in the handling for the bike’s stated purpose such as criterium racing, road races, spints, climbs, etc. That’s why I assumed you were asked about the other.

Cheers,
Jim
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Q: Hi Jim,
On my rear derailleur, when the chain is on the highest gear (smallest sprocket), the chain coming into the pulley loop "rubs" with the chain exiting the pulley loop. I've had the bike just over a year, and the chain has never been taken off, or even the back wheel, as far as I know. But it must not have been like this when I bought it. How can I fix this?

Thanks in advance,
John

A: First, John, you want to make sure the chain doesn't need to be this long. To do this, shift onto the big/big combination (large chainring/large cog). You want to make sure your bike will shift up there and that there's a little slack when it's in that position. If so, you can remove a pair of links and see if it shortens the chain enough to prevent it rubbing.

Keep in mind that you probably wouldn't ride in the gear that causes it to rub. That's the small chainring/small cog combination and that's a "crossover" gear that causes wear and rough pedaling. Since you never/rarely ride in that gear it doesn't matter if the chain overlaps on it. And, if you have to shorten the chain so much to prevent the rubbing that your bike won't shift onto the big/big, that's a worse problem. It's a problem because it's relatively easy to forget and shift onto the big/big. Even though you don't want to ride in that crossover gear either, if you mistakenly shift up there and the chain is too tight, it's possible for the chain to get stuck up there so bad that you have to get off and remove your wheel to get enough slack to get the chain off the large chainring.

So, you want to experiment a little bit to make sure you have the slack to take some links out to solve the rubbing but not lose the ability to shift onto the big/big.

Hope that makes sense,
Jim
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Q: Hi Jim,
I recently bought a pair of CLB brake levers, which require the brake cables to be routed through the handlebars. I've already done the drilling, but now I'm getting nervous as I haven't really found anything other than old photos on the internet that tell me conclusively whether or not this is safe.

The handlebars are upright bars, the swept back type you see on most dutch bikes for instance. Fairly new, not really used but quite a few scratches. It's made of aluminium. The holes are 5mm in diameter but drilled at an angle so it's more of an oval. They are about 4 inches from either side of the stem (and there are also holes at the ends of the bars to secure the levers). I've filed the edges of the holes as well.

What do you think? I'm still finishing the build so haven't ridden it yet, but before I do or before I let someone else ride it, I'd like some reassurance they won't fail while I'm pumping up a hill (or sloping street, rather) in the midst of London traffic. I'm rather small if that matters- 52kg, but I'll have mates riding it occasionally as well, who could weigh as much as 100kg.

Looking forward to your advice.

Regards,
Jacque

A: Boy, that's a tough one, Jacque. The only way to know for sure is to know more about the handlebars. For example, if you had a second pair of bars you could drill them too and then see if you can bend or break the bars, maybe hanging from them or having a heavy friend hang from them (after attaching them overhead somehow).

Aluminum bars like that definitely aren't made to be drilled and with wide bars like that you have a lot of leverage. But then 5mm is a very small hole. If the bars were steel, I probably wouldn't worry about it, but it's the aluminum that worries me. Even if you just put a deep scratch in aluminum it can lead to a crack over time.

Can you see inside the hole to get an idea of the wall thickness of the aluminum? And, how far from the clamping section did you drill the holes? Right next to the clamp is where most of the stress is centered. If you were inches away from that and if the bar is 3 or 4mm thick aluminum, I'd feel a lot better about it than if it's 1mm thick and the holes are close.

I wish I could give you better news but you're doing the right thing being safe about it. When handlebars break it almost always leads to a crash, often a serious one. I would go with levers that don't require drilling maybe.

Hope this helps,
Jim
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Q: Jim,
From your experience can the average rider tell the difference between the different steel tubing grades used in modern bicycle frames?
I know the cheap low-end stuff in WalMart bikes is dead and heavy, that is not the question. I have a 4130 chromoly Bianchi that really rides nice. I have a 631 Reynolds Jamis that rides excellent and is rather light at 18.5 pounds as a complete bike. So, when you move up to 853, 953 or the high-end Italian tubing, other than weight is the ride that much different? Also I understand the construction methods used such as TIG welding and lug and tube, but other than asthetics is there really any difference? It seems that you pay an awful lot for these upgrades.

Many thanks,
Bill

A: You sure know how to ask a tough question, Bill. Whether different quality steels ride differently is what riders have been debating since about 1886. The classic experiment would be to build identical bicycles with different steel and see if YOU could feel a difference. Some people say they can, some people say they can’t. In my experience, as long as the builder uses a great-riding geometry, and uses quality double-butted steel tubing, any steel bike will ride really nicely. I’ve ridden impressive Reynolds, Columbus, Tange, Champion, Ishiwata, Vitus, True Temper frames. If they get the best geometry and high quality tubing the bikes should all impress you with the ride. Actually that’s one of the limitations of steel – pretty similar characteristics from tubeset to tubeset. Which is why carbon has become so popular. Unlike steel, carbon can be manipulated almost to the molecular level by the builder. It starts as a thread, so by how it’s woven and laid up, much more can be done to fine tune the ride.

But, steel is still a wonderful choice for ride quality, durability, repairability, classic style, economy, and on and on.

If you are interested, I believe Jan Heine at Bicycle Quarterly recently did a test of similar steel bikes. You might visit his website and see if he’s offering it online. You may need to buy a back issue of his magazine to read it, but make sure it’s on the right topic first. I remember a test of identical bikes, but I’m not sure what all the parameters were. Still, it’s a very interesting magazine that not enough people know about so maybe you’d like to receive it.

Jim

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