Jim’s Tech Talk
By Jim Langley
To recap, last week was our first Tech Talk contest, for which we asked you to follow the clues in the story and tell us the specific problem causing my son-in-law Frankie’s Felt gravel bike to hesitate while shifting. The first person to come up with the answer would win a surprise prize – Park’s CN-10 Professional Cable and Housing Cutter: https://amzn.to/36b1W2x.
Having never held a contest in Tech Talk before, we weren’t sure how much interest there’d be. We needn’t have worried. There was an overwhelming response with a flood of comments both here on RoadBikeRider and on Facebook – since there are readers there, too. Famous roadies, legendary mechanics, renowned framebuilders, many of you, and bike industry insiders all took a try.
Not so easy
While putting the final touches on the story, I wondered if maybe the issue with Frankie’s shifting was so obvious that we’d have a winner straight away. Yet, going into the afternoon of the second day no winning entry had come in. So Lars and I discussed it and we decided it was time to drop a hint.
To get everyone thinking about it a little differently, I wrote that it was a more basic problem than the types of issues most of you were guessing. Also, that it followed the type of rule you’d hear from the head mechanic if you were a new wrench at a shop.
We have a winner!
About 45 minutes later, the winning answer came in, from David Zak of Saint Cloud, Florida, who correctly stated that Frankie’s bike was hesitating because someone “didn’t tighten the shift cable anchor bolt enough – so the cable was slipping” causing the hesitation.
A good lesson – never assume
What that head mechanic I mentioned might tell the rookie – or maybe your mom or dad while teaching you how to repair things is, “check every bolt with a wrench to be certain it’s tight, because it’s always the one that you didn’t check that’s loose.”
Where Frankie and I got in trouble on his Felt is that we assumed that the cable anchor bolt was tight. First, the bike shifted. If the bolt was really loose, the bike wouldn’t have shifted. Second, the bolt and cable looked right. There was no fraying or corrosion and there was an end cap in place. And third, the cable appeared squashed by the bolt and clamping plate as it’s supposed to be.
We didn’t discover that the bolt was actually slightly loose until we put a wrench on it and tried turning it. Instead of SRAM’s required 4 to 5Nm, it was probably – best guess – less than 2Nm. Whatever the actual tightness, it was not enough to prevent the cable from slipping when shifting up onto the larger cogs.
Impressed that he figured it out, we asked David to share some of his cycling background. He was kind enough to send this quick bio in which we learned that he’s been working on his own and friends’ bikes for a long time.
“I got the cycling bug back in the mid 80’s while in college in SoCal (first bike was a Schwinn Varsity). I soon learned that as a poor college kid the only way I could improve my ride was to do most of my own bike work, and soon I upgraded to an old Holdsworth frame with Campy Nuovo Record. I bought a book on how to build wheels, some basic tools, and with the help of mail order catalogs was on my way to being a full-on bike nerd.
My first real nice bike was a new ’85 Pinarello frame I got on sale, and thanks to my meager dishwasher money I was able to build up a racer. I still have that bike to this day. To have riding buddies I passed along my services to other poor college kids to get them into riding nicer bikes.
A 10 year stint in the Navy put my riding on hold for a while, but after settling into my career post-Navy I rekindled my passion for cycling and was soon wrenching bikes again in my spare time for buddies. I have way too many bikes right now, but my favorite rider is a 2008 Lynskey 240 with Campy Chorus 10, in silver aluminum for the classic look.
Although I’ve ridden my share of Shimano and SRAM, I am 100% a Campyphile and do lean Italian. At 55 I don’t get to ride or wrench as much anymore, but I still have a garage full of future bike projects to last me until I die. My wife has been very accommodating through it all too, God bless her.”
Thanks, David. And, congratulations. Your prize is in the mail.
Is it wrong to put quick-release levers on the right side?
To wrap up, I wanted to explore an issue on Frankie’s bicycle that many people spotted and thought was wrong. It’s that his quick release levers are located on the right hand (drivetrain) side of the bike. That’s actually how his bike shop set up his Felt when it was new.
As you know, traditionally on road bikes, the QR levers are located on the left side. But, with the introduction of disc brakes on roadsters, there are good reasons you might want to put your levers on the other side.
The first thing that I recall that raised awareness of potential problems with QR levers on the left side of disc brake bikes was a huge Shimano recall. The issue was caused by riders forgetting to tighten their QRs and then having the lever swing around and go into the rotor, which could cause an awful crash.
Yes, it’s technically the cyclists’ fault for not tightening the QR, but it was treated as a recall that the lever could rotate far enough to reach the rotor.
If you’re interested in this issue, here’s a link to an old story on it: https://www.velonews.com/gear/seventeen-brands-recall-1-5-million-bikes-for-quick-release-issue/. At the top is a photo showing a lever touching the rotor.
Beware the rotors
One of the things to come from that recall was professional mechanics being told by their brands to put the levers on the right side. And, there are other reasons to do it. Rotors can heat up a lot on long descents. Should you need or want to remove a wheel when a rotor’s hot, having your hand next to the rotor probably isn’t the best idea. And, since it’s common to grab the seatstays or chainstays when closing levers, it’s easy to mistakenly grab the rotor.
Maybe the best reason is that the hand closing the QR is also probably the one that changed the flat or fixed the bike on a ride. The last thing you want is to get grease, oil or sealant on your rotor and/or brake pads. By keeping the levers on the opposite side that’s much less likely to happen.
Ultimately, it’s your choice on which side you place your levers. Also, more and more companies make it a non-issue by using through axles these days. If you have those, you probably have nothing to worry about. (Just be sure if it’s required, to carry the right wrench to remove the wheels so you can fix flats.)
Thanks for participating in the contest! I hope you had as much fun as we did.
Ride total: 9,779
Jim Langley is RBR’s Technical Editor. He has been a pro mechanic and cycling writer for more than 40 years. He’s the author of Your Home Bicycle Workshop in the RBR eBookstore. Check out his “cycling aficionado” website at http://www.jimlangley.net, his Q&A blog and updates at Twitter. Jim’s streak of consecutive cycling days has reached more than 8,000. Click to read Jim’s full bio.