Jim’s Tech Talk
By Jim Langley
You might recall that a few months ago, a reader named Barbara, who’s been cycling for years, wrote in for help with her brand new Bianchi Venezia (photo). I offered a few tips and there followed many excellent suggestions from you readers – thank you!
Since her first email I’ve kept in touch with Barb and she’s read your comments and appreciates all the help. But her bike is still scaring her. Today, I want to follow-up to let all of you know what’s been going on and the latest development.
Originally she described riding her new Bianchi like this:
“Can someone help me understand why on my new bike I seem unable to control my front wheel? I have barely missed striking a parked car. Our streets often have bike lanes and I wobble around in them. The bike makes very wide wobbles.
This is new to me. I have ridden bikes for years but never had this problem. I feel amateurish. The bike shop supposedly tightened the handlebars. That was no help.
I am now very slightly but not visibly tremulous. Is it me or possibly a bike problem?”
To backpedal to Part 1 and read our suggestions for Barb and yours: https://www.roadbikerider.com/barbs-wobbly-bianchi/.
Bucking Bianchi
Fast forward to a couple of weeks ago, and Barbara sent this scary follow-up:
“Have you ever heard of this? I fell from my bike with the bike on top of me. This happened three times.
I realize now that all three times I braked hard and quickly because the front wheel was moving me in a dangerous direction. My hard braking caused the front wheel to turn, fold toward the bike and the bike lost balance falling in the direction of the front wheel.
Something is daemonic about my bike.”
A wobbly bike is one thing, a bicycle that ejects you is much worse. So I immediately wrote back, “Wow, that’s awful, Barbara. Something’s wrong for sure. I wish you lived near me. I’d be over to ride the bike and figure this out. I live in Santa Cruz, California. You’re not nearby are you? [Barbara didn’t say so I assume she doesn’t.]
I’m still thinking that what you need is to find a test pilot to ride your bike and see if they can get it to misbehave as it does for you.
Another option might be to return the bike to where you bought it and demand a refund and then buy another bike made by another company. Most new bikes are covered by guarantees and yours might still be under warranty. That might be something to consider.”
More Ideas
As I waited for Barb to reply, I made this list of possible problems to go over with her next time:
- Step through frames can be prone to wobble because there’s one less bracing/stabilizing frame tube up high.
- High handlebar positions can lighten the front end to the extreme potentially allowing the front wheel to swing right and left on its own because the tire isn’t held against the road the way it would be if more weight was on it.
- A locking brake could be a loose caliper, loose wheel or damaged rotor
Problem solved?
I was ready to send the additional ideas I just mentioned to Barb when she updated me. Luckily, I didn’t need to. Here’s her most recent email:
“I took my bike to a top notch bike shop. The bike repair techs checked it. They said the headset is fine but the handlebar is too high and at the wrong angle. A bolt in front of the handlebar was also loose.
The tech then rode it for ten minutes. No problem. She did point out the bike geometry plays a part in my experience with the bike. She said that if it isn’t correct for me I should return it (the bike still tilts when dismounting).
I rode the bike briefly on the way home. No trouble. It felt more comfortable. The handlebar is now straight across and lower. I will see how it goes as I ride it more.”
To me this is great news and I bet all of you who helped will agree. I think you’ll also agree that if it’s still difficult to control the bike even if only when dismounting, Barb should consider a different bike.
Thanks again for helping Barbara and let’s watch the comments as she may post more once she’s had a chance to put in some miles.
10,123 Daily Rides in a Row
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 cycling streak ended in February 2022 with a total of 10,269 consecutive daily rides (28 years, 1 month and 11 days of never missing a ride). Click to read Jim’s full bio.
We followed a white mobile camper on US 2 going west yesterday that had bikes covered with “your” bike cover and Wisconsin plate. We were driving a tan Toyota pickup with cap, MI plate. Was that you in the camper?
No, not me, Jack. We’re checking out amazing pueblo ruin sites around Flagstaff right now.
Thanks!
Jim
I am concerned that the first bike shop which worked on the bike “repaired” the bike but allowed it to leave the shop with a loose handlebar in the incorrect position. The shop manager/owner has a problem with those hired to repair bikes…if they allow bikes to leave the shop in a dangerous condition.
Barb should really have a discussion with the shop manager/owner.
My view only…
I’m concerned, too, Walt.
Good point, thank you!
LBS? Try a different shop and get second opinion.
Best advice I ever got about wobble was to apply pressure to a pedal in its down position to torque the frame. Works quickly and is easy to remember–also easier to apply than leaning one’s knee on the top tube, say.
I have ridden “ladies’ frame” bikes, like the one in the photo, that were _extremely_ prone to steering shimmy. This is no surprise. The frame has far less torsional rigidity than an otherwise-similar frame with a top tube, and so the frame’s flexibility can create shimmy.
Note my use of the words “otherwise similar.” The frame in the photograph appears to be made from small-diameter steel tubing. It is possible to use oversize tubing to make frames with both good torsional rigidity and the increased standover clearance that the subject frame has.
On Page 24 of this linked file, you can find some of my further thoughts on steering and stability.
http://notfine.com/rivreader/RR37.pdf
Thanks for the link, John!
Appreciate it!
Jim
Maybe she is too strong a rider for this frame. Would a more leisurely rider have the same problems?
Doug, my experiences with steering shimmy have not involved hard pedaling. You can get shimmy when coasting.
The headset should perhaps be over-tightened slightly if the bike shimmies while riding no-handed. This was a problem on my old (diamond-framed) 10-speed when I was a kid and there needed to be a little bit of damping in the headset. The idea of having the handlebars lower is a good one. On a regular diamond-framed bike something like 1/3rd of your body weight is on the handlebars which increases damping.
I am looking at the photos of this bicycle and it does not seem to have very much trail in the front fork, so the steering might be skittish. I am not sure how much you could do about this other than adding a loaded handlebar bag or changing it out for a fork with longer trail. The trial on this front fork should be measured.
Donald, I think you have fork rake and trail mixed up. They are not the same. See the article I linked to in my comment.
I guess the best solution if the front fork has low-trail, would be to simply take the fork to a steel frame builder to change the fork, and make sure to adjust the brake blocks after the trail is increased to at least 45mm. Also, by using a longer stem, some more of the rider’s body weight can be shifted onto the handlebars, and the movement of the bars will need to be greater to execute the same-radius turn, and both will increasing stability.
This another example of a “Bike shop ” selling what they have instead of what you need. Clearly their competence is sorely lacking letting the bike out in an unsafe condition. Im glad Barb found someone to adjust the bike and repair the problems. Hopefully this does not put her off cycling.
Articles like this are a reason I support RoadBikeRider Newsletter. Thank you for clearly laying out the problem and various solutions.
You’re very welcome, Bruce. Thanks for reading!
Jim
You’re very welcome, Bruce. Thanks for reading!
Jim