Technical Editor & Tech Talk Columnist
Probably like most of you, I fell for cycling as a kid. But unlike most of you, when it came time to get a real job, I stuck with what I had done in college — and with what I loved — and kept working as a bicycle mechanic. That was my profession between 1972 and 1989 in shops in New Hampshire, Vermont and California, where I live today. During those years I assembled and repaired thousands of bikes. Sold a bunch too. Built a couple of frames plus hundreds of wheels. And I introduced the great sport of cycling to legions of customers.
I learned everything I could about bicycles and repairing them through experience, reading and from all the people kind enough to show me the way. Plus, I got serious about riding, first touring (across the U.S. in 1979) and then racing — everything from road and cyclocross to mountain and triathlon. Road racing is still a passion. In 1989 my cycling background and degree in English led to a full-time job with Bicycling magazine.
At Bicycling I became the technical editor, handling how-to articles, buyer’s guides, bicycle road tests, the Tech Q&A column and the New Products department. I also served as the magazine’s curator of bicycle history and collectibles. I did all of the wrenching, too, before we expanded the office and hired a mechanic. And I was in charge of the photo shoots, experience that came in handy when I was asked to rewrite the photo-intensive book Bicycling Magazine’s Complete Guide to Bicycle Maintenance and Repair.
Today, I put my cycling knowledge to use as RBR’s Technical Editor and Tech Talk columnist and author of the eBook Your Home Bicycle Workshop. I’ve written for RBR since 2003. In my real job I work as an Associate Mechanical Engineer at Praxis Works Bicycle Components, where we design and manufacture chainrings, cranksets, bottom brackets and wheels. I also maintain my personal bike websites www.jimlangley.net and jimlangley.blogspot.com where I help people get into cycling, and share info and photos of many of my cycling interests. You can also follow me on Facebook and Twitter.
Of course, I’m still crazy about cycling and ride literally every day. In fact, I haven’t missed a day in more than 23 years (for those of you counting at home, that’s more than 8,500 consecutive days!). My original goal was to ride daily for 10 years. But after reaching that milestone I kept right on going, because bicycling is what I do and who I am.
I regard to Jim’s most recent article on pedals, he says “James Starley, back in the dawn of cycling, to tighten as you pedal – which is why pedals don’t need to be too tight when installed in order to stay tight.” I take issue with that and say that pedaling direction contributes to loosening pedals not tightening. If the bearing on the pedal were to seize, the pedal would come loose from the crankarm.
Eric is exactly right. Pedaling loosens pedals and keeps them from getting too tight. Jim, I have followed your writing for years and I am a huge fan. But I’m afraid that here you perpetuating a common misconception. When the bearing starts to lock up on a pedal, it will actually unthread itself. With a pedal partially threaded on, grab the pedal axle and rotate the crank–it will come right off.
These posts about thread direction are old, but haven’t been corrected, so I’ll chime in. It’s true that the threading of pedals will cause them to unscrew if the pedals loosen up and that happened to me several times as a kid, riding the simple, unsealed pedals of the day on old bikes that lived much of their lives on their sides in the yard in all kinds of weather. I don’t recall ever having a pedal seize up in the 50+ years since I moved up to quality road bikes, though I’ve worn out many. I also recall the difficulty of riding on a pedal that had lost its moving parts and had been reduced to an axle sticking out of the crankarm, but addressing that possibility isn’t part of the design brief for bicycle pedals, either.
What was considered in the evolution of pedal and crank design was how these parts interacted in .normal use, and that’s where the left threading of left pedals and right bottom bracket cups sprung. The issue is that there is always a tiny amount of clearance between male and female threaded parts. This difference is called an allowance, or clearance, and the amount is selected based on manufacturing costs and application. It is also impacted by tolerance, or the amount a measurement is allowed to vary from its design value and still be acceptable. If you simplify the two threaded components to concentric cylinders, the interaction between them becomes more obvious.
One simple way to simulate this interaction is to hold your left thumb and forefinger together to make the OK symbol and place your right index finger into the hole. The fingers on your left hand represent the pedal hole in the crankarm, and your index finger represents the pedal axle. Hold your left arm straight up and slowly bring it down, pivoting at the elbow. If you observe the orientation of your index finger as your arm moves, you will notice that to keep the point of contact at the changing 6 o;clock location of the hole, you have to rotate it clockwise, whereas if you grip the finger tightly, it is forced counterclockwise. This means that the natural force of the pedal in motion is to apply a small rotational force on its axle clockwise on the right side of the bike and the opposite on the left. The converse is true for threaded bottom bracket cups, where the right (drive) side cups are left-threaded on British and (long obsolete) Swiss threaded systems. Many riders of Italian and French threaded frames, myself included, know all too well what can happen when the fixed cup of one of these bikes works loose. It doesn’t take long for the cup to walk out of the frame and leave you stranded. Rare is the rider who carries the tools necessary to tighten the cup back up and it can take an ungodly amount of torque and/or plenty of Locktite to keep them in place when there’s a bit too much clearance in the thread. The famed Campagnolo shop tool kit included a cheater bar that was designed to be used with their bottom bracket fixed cup tool to provide the extra grunt necessary to properly tighten and loosen Italian cups.
When I do the thumb and index finger demonstration it seems that Stephen has it backwards. When you grip the finger tightly it moves clockwise – not counterclockwise.
Jim I would like to see an article about Carbon Fiber- i.e. I recently bought a carbon fiber handlebar and now I have 2nd thoughts about it not being in a wreck or loosing its integrity. Any thoughts about buying used carbon fiber parts, especially handlebar and forks would be appreciated.
I agree with Charles Alt and I stand by my original statement. After trying a Stephen’s test, I’m more convinced than ever. NORMAL PEDALING MOTION TENDS TO LOOSEN PEDALS-Sorry for shouting.
If you really want to test it- put your pedals on as loosely as possible. How far did you get before the came out?
I was wondering if you could address if ultrasonic parts washers are preferable to a regular parts washer for cleaning cassettes, chains, etc. I was looking at the ultrasonic ones recently and was surprised how inexpensive they are.
Thanks,
Amu
Jim, I had a question that I thought you might be able to answer on behalf of myself and many others who find themselves having to replace Campagnolo drivetrain components.
It seems logical to me that the back end of your bike should remain consistent (eg. I am aware that you should not try to use SRAM or Shimano components on a bike equipped with Campy – cassette, derailleur, etc.), but that the front end can handle some mixing and matching. I have trouble seeing how a Campagnolo front shifter would be unable to deal with a Shimano or SRAM chainring group, with a compatible chain (e.g. 11-speed chain for an 11-speed cassette/rear derailleur). Is not the key factor the ability of the front derailleur to move the chain between the 2 chainrings? and therefore, whether it’s a Campy or a SRAM ring should make no difference?
On the same topic, it seems to me the width of the chain is the limiting factor – therefore you could use an 11-speed SRAM or Shimano chain on an 11-speed Campy gruppo.
Does the same apply in reverse? i.e. if all you have on hand are 11-speed chains, is there a reason you could not use them on an older 10-speed system?
Hi Jim,
I am not sure where you live and ride (daily!) but here in Utah in winter, I have a problem with gear shifting in cold temperatures. I am talking in the -20 to -5C ( -4 to 23 F) range, and yes, living in the mountains of Utah, this is pretty common during my commutes to work. The problem seems to be worst for the front mech and can cause it to stick on the big ring no matter how much slack is in the cable. But rear shifting is also pretty slow at times.
Is there a suitable lubricant, or what other tricks do you suggest?
I am using a gravel bike with Shimano GRX for commuting and while I try to keep it clean, you can imagine the roads are pretty sloppy around here in winter, especially this winter with record snow (hooray!)
Thanks,
Rob
Jim’s bio omits that he is great company, and just an all around nice guy. His bike accomplishments are impressive, but doing all that stuff without turning into a curmudgeon is even more rare. Seeing him graciously handle all manner of people with a smile and a kind word is most amazing.