Happily, none of my current bikes speed wobble. If one did, I’d be looking at this new product from Cane Creek, which claims to address it:
If any of you have tried it, I’d love to hear whether it’s resolved it!
Never tried it - in theory, it could work, as the steering acts like a mass-spring-damper system (reducing the complex math to a first-order system), and anything that changes the mass, the spring or the damper (in this case it’s the damper) will change the resonant frequency. I’m not sure what this does to the straight-line stability, however; it may act as a sticky headset, meaning while it dampens high-speed wobbles, it may increase low-speed instability. Anyone who has ridden an overworn headset with bearing indentations in the races knows the feeling, and knows how you can’t ride such a bike hands-free.
Fairly sure it is aimed at MTBs
Assuming that everything on the bike side checks out properly (alignment, components, no strange voids, etc), changing the HTA is kind’ve like changing pickups and buying a new amp when what you needed to do was learn how to tune your guitar.
No insult to the OP. Just recognize that geometry (esp on road + city bikes) has been pretty well dialed for a long time … like, at least 3-4 months maybe even 5 
. On top of that, mass produced bike geometry has to fit within the ISO 4210 specifications (one reason why tiny road bikes have stupid slack HTA).
If you can’t isolate the issue with the bike then it’s the rider. Could just be that the rider + the bike are like me an all my exes – self destructive, toxic combinations.
Posting this as I have just had this occur on my TT bike during a high speed decent at over 40mph. This was extremely violent side to side and my first though was somehow I’d had a serious mechanical failure in my front wheel or forks.
As I was not in the bars I could gently ease the back brake on and although it took a few seconds the shaking of the bike stopped as the speed came down again, although it took the rest of the ride for me to calm myself down as my heart rate data can attest.
Hers some data and the moment you can see my heart rate turn around mid decent. I did manage to do a close to 40mph decent later in the ride.
Out of interest, this happened on the 70.3 Weymouth course, which we rode yesterday even though the event is pushed back a year. It’s a great course with nearly 4000ft of climbing for your 56 miles.
Possible causes are hard to pinpoint, this was likely my first time at over 40mph on this bike, but also I’d had back wheel issues rubbing my frame and had to stop to manually adjust the wheel. To complicate things further I was running latex tubes for the first time.
From what I’ve read I’m not inherently blaming any equipment here, rather that it is an oscillation at some sort at high speed in certain situations with heavier riders / high seat posts. For completeness sake, here’s my equipment list
Cervelo p3 2018 / Zipp 404 fire crest front and rear / conti GP5000 25mm / Vitoria latex tubes
I’d be very interested in hearing more about your experiences with descending on the Diverge. I ride a 2018 Diverge Comp E5, and I just can’t seem to get confident descending on it. Unfortunately, I don’t know how much of that is the bike’s fault, and how much is my fault. All I’ve been able to find is that the Diverge is considered a very stable bike.
When I get up to about 60 km/h, it feels like the front wheel is just about to begin wobbling (almost certainly fueled by my tenseness due to lack of confidence), and I have to touch the brakes a little. In conditions with wind gusts, I can’t go above 50 km/h. For a short while I rode a pair of 60/88mm deep rims, but I had to sell them, because that front wheel was really nervous. I currently ride a pair of Zipp 30 Course with tubeless GP 5000.
I have found that speed wobbles occur more for me when I have too much weight on the handlebars - at which point braking makes it worse. Putting more weight on the pedals by slightly raising my butt helps.
1 Like
Just spent 30min reading about Hopf bifurcation…
The response you linked to is interesting as it suggests any bike will have an intrinsic speed at which speed wobbles begin, which is determined solely by the stiffness of the frame.
This suggests that the only things you can do acutely to stop the wobbles are to go slower, or increase the stiffness of your bike - I wonder if clamping their top tube of the bike with your thighs is effectively increasing the stiffness of the bike/rider system, therefore increasing the critical speed at which the wobbles start, and allowing a stable equilibrium to reform at the speed you’re going.
I also wonder if putting more weight on your bars effectively decreases the stiffness of the system because of the presence of the pivot point at the fork where your weight is spread on both sides. Hence putting more weight onto your pedals would help too.
1 Like
Looks like the TR crew actually did a podcast on this issue.
1 Like
I’ve always heard this is the way to stop a wobble, fortunately never had the opportunity to test it out
1 Like
I just had similar issue with high speed wobble on TT bike this weekend.
It was cold, I was shivering, the road was wet so brakes sucked on carbon wheels.
But slowing down did help.
Just did bike clean and check. Nothihg obviously wrong.
What my later investigation led to was that a wider front tire might correct the problem.
1 Like
Marginal Gains podcast talked about this awhile back.
https://podcasts.apple.com/us/podcast/bifurcation-and-marginal-gains/id1449434247?i=1000492704533
1 Like
Having experienced speed/death wobbles like you eat skittles, here’s a couple of thoughts…
- Had a 2019 Roubaix w/that future shock 1.5 headset with Roval CL50’s, running Conti 4000’s and now 5,000’s at about 100 psi. Got speed wobbles mostly going downhill and enough so that I started doing the little-old-lady-from-Pasadena thing down decents. I’ve had the headset serviced, wheels trued, etc… The second to the last time, still feathering the brakes, the wobble took me across the double yellow line and into oncoming traffic… fortunately no cars were coming, but riding with a friend, he saw it all. I contacted Spec and took the bike to their company store. Two weeks later, finding mostly nothing except rebalancing the rear wheel, I was given the bike back. Had a few more wobbles after but had pretty much given up doing anything more than a slow crawl down a hill. Brakes be damned.
Over a month ago, on a straightaway during an aggressive group ride, I hit about 35mph and it wobbled. That was a first - and that was the last… I took the bike to the LBS and said I was done with it. I got a Tarmac SL7. Transferred my saddle and wheels over to the new bike.
- I got a wobble today on a straightaway going 30mph and immediately took it back to the shop. They tightened the headset down some more and advised of an interesting observation. One of my tires was out-of-round. When spinning the wheel, you could see the tire actually bounce. Weird I know. So we changed the tires and will see what happens.
SERVICE
Via the process of elimination outside of a gust of wind, 1. focus on the headset first (alignment/tightened down). 2. Wheels trued (front/back). 3. tires. 4. Fork irregularities.
WOBBLE MANAGEMENT
As for stopping a wobble, 1. Don’t panic! 1A. Breathe! 2. Don’t over grip the handlebars - try and relax. 3. Gently engage the rear brake until the wobble stops. 4. Try and sit upright. 5. Pedaling thru a wobble works for some people, it doesn’t for me. 6. Clamping your legs around the top tube MAY work (tried it once but it just shook me in conjunction with the bike). Try it but don’t marry yourself to the idea it will. 7. Definitely shift your weight OFF the handlebars if you were going heavy on it. 8. Try and center your weight on the pedals. I find keeping your feet at 9 and 3 o’clock helps.
Realize you’re gonna be terrified and definitely skittish, but do those things to stop it and it will.
1 Like
I’ve never had a speed wobble on a bike but I have on rollerblades. Solution there is to shift your weight backwards. I expect on a bike changing anything could work; you’re the largest mass in the system and you’ve got five points of contact with the bike you can change. Move your hands out or in, clamp the top tube with your knees, put your weight more on your saddle, etc.
Of course a driven oscillation is going to be harder to stop. If I did the math right, if you have an out-of-round tire, then at 30mph you’re driving an up-down motion at 6.3Hz, which is at the low end of the range involved in speed wobble according to the cyclingtips article.
1 Like
I’m glad you did the math on that cause I hate math… 
When I was a new rider, and refused to believe that my inexperience of very fast (50+mph) descending caused my speed wobbles, I took my bike to a LBS to make sure everything was dialed. I then tried to descend again…more wobbles. I then tried the knee clinching trick…and it helped considerably but was still present.
After practicing many times with the clinching trick, I gained more confidence. I can now hit lengthy descents topping 54mph without knee clutching on the same bike.
Body rigidity from lack of confidence will amplify resonate frequency…just practice and it will go away IMO
1 Like