Speed wobble with new wheels!?

paulmgreen

I've fitted new wheels today ..... Went out for a ride .... Came to a long downhill section.... Hit 33mph and suddenly got a massive speed wobble..... Very nearly uncontrollable.!?

I can't figure why this should happen? The new wheels are perfectly straight as they should be..... Spin easily.... Tyres are mounted straight ... No wobble on bearings .....


How can this be ?

imposter2.0

Bit more info mate - bike, wheels, tyres, surface, that kind of thing...

gethinceri

Road surface, gust of side wind, too tight a grip on the 'bars?

paulmgreen

Wind was a slight tail wind. .......... No cross wind .....


Bike is a specialised Allez ... New wheels are Saturae SC20 . Fitted new wheels with original tyres ..... Which are in good condition have only done 500 miles ....free hub had failed on standard OE wheels.

I have checked wheels and tyres for trueness and all seems fine ..... Tyres are both facing right way for Rotation arrow marking ...... No play in bearings ....... Both appear positioned correctly in frame and QR tight

smoggysteve

You can get speed wobble for what seems no damn reason at all. It could be the wheels. It could even be the frame or fork. Don't judge based on 1 ride. If it continues then return them but it could just be a one off. If it is the wheels then look as spoke tension. Some wheels have a lower spoke tension that allow the wheel to flex a little. They will still be perfectly true when you spin it in your hand but rubber side down with you and the bike on top they can start to flex about in all directions under load.

ayjaycee

Have you ridden down the same hill at that speed on the old wheels and same tyres? If so, did you get the wobble? If not, it could well be something to do with the new wheels and they might need to go back as not fit for purpose. Sometimes, sh1t just happens and, personally, I would do the same run and try to replicate the wobble before going assessing the way ahead. At least this time you will be ready to take action if it does happen again.
My final thought is that if the OEM tyres were those Specialized Espoir things, chuck them out whatever happens - there are much better options out there - just use the search her on BR for recommendations.

Frank Wilson

Pretty basic but is the wheel correctly in the drop outs?

debeli

The above response is my first guess in the scenario described.

I've seen this more than once and done it myself more than once.

Loosen each wheel and bear down on the bike as you close the QR lever. It is extremely easy to tighten a QR lever while the wheel is not quite inserted fully into the drop-outs on both sides.

This seems to have become slightly more common now that so many people remove and replace wheels on a workstand and so have to keep the wheel supported while closing the QR.

Do check that... and prepare to be slightly surprised.

Frank Wilson

Debeli wrote:

The above response is my first guess in the scenario described.

I've seen this more than once and done it myself more than once.

Loosen each wheel and bear down on the bike as you close the QR lever. It is extremely easy to tighten a QR lever while the wheel is not quite inserted fully into the drop-outs on both sides.

This seems to have become slightly more common now that so many people remove and replace wheels on a workstand and so have to keep the wheel supported while closing the QR.

Do check that... and prepare to be slightly surprised.

Having experienced exactly the scenario you describe is what lead me to suspect the obvious. Must admit after replacing wheels on a work stand I now always put the bike on the floor, loosen the QR and give the wheel a "slap" into place before doing up the QR.

ayjaycee

Maybe I shouldn't have done but I assumed that wheel correctly fitted to the drop outs or QR tight enough were so basic as to not be worth suggesting!

Also (and slightly off topic), it occurred to me that if the OEM tyres only had 500 odd miles on them then the original wheels were the same and probably, therefore, not too old - hopefully, the 'Saturae' wheels were a warranty replacement but, if not, the OP might also consider returning the originals if they are less than 12 months old.

Jerry185

Definitely replace. I had a speed wobble on my first bike and never found out the cause (tyre, wheel, frame, headset). Problem continued as the LBS kept saying they thought they had fixed it.
I, too, was at 30+ on a downhill straight when I used the brakes - out of control and on wrong side of road with a car coming up. Somehow, broadsided the bike to a stop. Car driver must have thought I was a loon. That was it for me.
Bike supplier took it back no issues

debeli

Jerry185 wrote:

Definitely replace. I had a speed wobble on my first bike and never found out the cause (tyre, wheel, frame, headset). Problem continued as the LBS kept saying they thought they had fixed it.
I, too, was at 30+ on a downhill straight when I used the brakes - out of control and on wrong side of road with a car coming up. Somehow, broadsided the bike to a stop. Car driver must have thought I was a loon. That was it for me.
Bike supplier took it back no issues

This is not the best advice I have ever read on a cycling (or any other) forum.

I think it might even be a Mickey-take too subtle for me to have understood....

I am still riding many years later on cycles that have given me moments of horror and terror on 35-40mph descents. In every case there was a tweak or an adjustment or a tightening that I either believed or imagined had cured the issue.

Sometimes it was clear, sometimes I was guessing. But if the geometry is right, the rims are true, the spokes are twangy and the tyres at the right pressure, then ride it - do not return it.

One of the finest feelings on a bicycle is to re-address a fast descent after having had a lane-swapping, chaotic, heart-stopping tank-slapper on it and finding the tweaked and trimmed machine goes down it like a guided missile.

Go home, set it up right, take a deep breath and go again. You know you want to.

topgunsteve

Out of interest, what size is the Allez? Some bikes with taller headtubes can suffer from speed wobble as they're not as torsionally stiff. Dan Empfield did a good article on this over on Slowtwitch.com a while ago. The premise being that as the bike size increases the manufactuirers don't always account for the decreased torsional stiffness. Maybe worth a search to see if any others have had this with the Allez (never ridden one myself)

http://www.slowtwitch.com/Tech/Speed_Wobble_5033.html

"Speed wobble was occasionally a problem in the "old days" when bikes weren't very stiff, and when they didn't have much in the way of a damper. Steel bikes were fairly flexible, undamped, springs. Once a particular speed was reached the frame started to shimmy."

I'm probably over-egging it here as it doesn't sound like it happened with the other wheels. As previously sugegsted, check spoke tension, wheel balance etc.

paulmgreen

It's a medium Allez. I've checked everything over and couldn't see anything obvious...... Got a couple of things I'm Going to try at the weekend ... Will report back .... Thanks for the input fellas

Jerry185

Debeli wrote:

Jerry185 wrote:

Definitely replace. I had a speed wobble on my first bike and never found out the cause (tyre, wheel, frame, headset). Problem continued as the LBS kept saying they thought they had fixed it.
I, too, was at 30+ on a downhill straight when I used the brakes - out of control and on wrong side of road with a car coming up. Somehow, broadsided the bike to a stop. Car driver must have thought I was a loon. That was it for me.
Bike supplier took it back no issues

This is not the best advice I have ever read on a cycling (or any other) forum.

I think it might even be a Mickey-take too subtle for me to have understood....

I am still riding many years later on cycles that have given me moments of horror and terror on 35-40mph descents. In every case there was a tweak or an adjustment or a tightening that I either believed or imagined had cured the issue.

Sometimes it was clear, sometimes I was guessing. But if the geometry is right, the rims are true, the spokes are twangy and the tyres at the right pressure, then ride it - do not return it.

One of the finest feelings on a bicycle is to re-address a fast descent after having had a lane-swapping, chaotic, heart-stopping tank-slapper on it and finding the tweaked and trimmed machine goes down it like a guided missile.

Go home, set it up right, take a deep breath and go again. You know you want to.

Seriously, Debeli? This was a life-changing incident and the last one I would ever do. To have got back on that bike going down hill would have been reckless for me and any other poor b*gger in the way. How can preserving life and limb be 'not the best advice?'

smoggysteve

Jerry185 wrote:

Debeli wrote:

Jerry185 wrote:

Definitely replace. I had a speed wobble on my first bike and never found out the cause (tyre, wheel, frame, headset). Problem continued as the LBS kept saying they thought they had fixed it.
I, too, was at 30+ on a downhill straight when I used the brakes - out of control and on wrong side of road with a car coming up. Somehow, broadsided the bike to a stop. Car driver must have thought I was a loon. That was it for me.
Bike supplier took it back no issues

This is not the best advice I have ever read on a cycling (or any other) forum.

I think it might even be a Mickey-take too subtle for me to have understood....

I am still riding many years later on cycles that have given me moments of horror and terror on 35-40mph descents. In every case there was a tweak or an adjustment or a tightening that I either believed or imagined had cured the issue.

Sometimes it was clear, sometimes I was guessing. But if the geometry is right, the rims are true, the spokes are twangy and the tyres at the right pressure, then ride it - do not return it.

One of the finest feelings on a bicycle is to re-address a fast descent after having had a lane-swapping, chaotic, heart-stopping tank-slapper on it and finding the tweaked and trimmed machine goes down it like a guided missile.

Go home, set it up right, take a deep breath and go again. You know you want to.

Seriously, Debeli? This was a life-changing incident and the last one I would ever do. To have got back on that bike going down hill would have been reckless for me and any other poor b*gger in the way. How can preserving life and limb be 'not the best advice?'

I will back up Debeli on this. You know when, where and how fast the wobble occured. You can go into the same descent with eyes open and be prepared if the wobble begins. No one says you have to go hell for leather and ride dangerously. A speed wobble can happen to anyone at anytime on new or old wheels. Its happened to me on rides I've done countless times before on the same setup. Only for the wobble to never manifest itself again in the same place. I would suggest doing the route again and just watching the speed to see if anything happens. If not then pick up the pace. If I stopped riding every time something unexpected happened I'dnever leave the garage.

fenix

I've only ever had a speed wobble once - new bike, fierce side wind and could barely control it.

Never happened again in all the years i rode it.

charlie_potatoes

Seismic activity?

darkhairedlord

Those dodgey allez headsets again...

paulmgreen

@darkhairedlord .... all of a sudden coinciding with new wheels?? may be not?

fenix

And you'd ridden that hill on the old wheels before with no drama ?

mct88

Common factors between the 3 bad speed wobbles I've had in 5-6 years...
Nothing wrong with bike.
Above 60kmh 40mph(ish)
Road surface finishes varying on the descent.
Bad weather, wet, windy, cold.
Me being cold stiff and probably too tight on the bars.

I read up after the first one and found advice to relax, weight gently off the saddle and one crank arm down with weight on. This worked for me the second and third time.

I agree the fact its happened on new wheels should not be overlooked - Do whatever you have to do to have confidence in your kit. Whether that's check it thoroughly yourself, or ask/pay someone you trust do it. If you have to return/replace wheels that could well be perfectly good to trust your bike... So be it!

darkhairedlord

I always slide back on the saddle and brace aganst the top tube with the inside of one leg. No idea if it helps but yet to fall off doing it.

cycleclinic

If speed wobble persists at a particular speed then it is a resonance effect caused by an interaction between the wheel and fram/fork. It can be an aerodynamic effect in it cause. Resonmce cannot be solved without changing parts. new wheels will remove the problem as would changing how much weight there is over the front wheel (this can dampen the wobble). riding through it will solve it. Holding speed at the wobble is a bad idea.

I have never had it to me but I do get calls about this and when I quizz the caller it scream resonace to me and there is no way to fix it without chnaging the wheels.

darkhairedlord

thecycleclinic wrote:

If speed wobble persists at a particular speed then it is a resonance effect caused by an interaction between the wheel and fram/fork. It can be an aerodynamic effect in it cause. Resonmce cannot be solved without changing parts. new wheels will remove the problem as would changing how much weight there is over the front wheel (this can dampen the wobble). riding through it will solve it. Holding speed at the wobble is a bad idea.

I have never had it to me but I do get calls about this and when I quizz the caller it scream resonace to me and there is no way to fix it without chnaging the wheels.

Nail on Head.
The wheels are one part of the "whole system" and it is the "whole system" that is giving the problem. It could be that changing another part of the system will fix the problem, or it could make it worse.
Short of ditching the wheels I would look at other elements that are causing in-balance in the system during high speed descents:
Rider position on bike; too far forward, too far back? cheap to fix
Hands in the drops; at the back of drops or front of the drops? cheap to fix
Riding the ridges on the tarmac layup? try meandering down the slope so the tyre doesn't track the natural lay of the tarmac. Again, cheap to fix.
Headset too loose; remember, its the "whole system" so the headset may be amplifying the problem. Putting some very heavy grease in there may dampen the steering enough to do the job. Cheap fix.
Control the wobble by bracing against the top tube. Cheap fix.
Too much input from the rider, over-correcting! let go of the bars...OK, so still keep your hands there but just loosen the grip.
If all else fails either ditch the wheels and try something else..but...the issue will nag you and might return with different wheels.
Finally, get shot of the bike and try something with different geometry/material characteristics.

Jerry185

Nail on Head.
The wheels are one part of the "whole system" and it is the "whole system" that is giving the problem. It could be that changing another part of the system will fix the problem, or it could make it worse.
Short of ditching the wheels I would look at other elements that are causing in-balance in the system during high speed descents:
Rider position on bike; too far forward, too far back? cheap to fix
Hands in the drops; at the back of drops or front of the drops? cheap to fix
Riding the ridges on the tarmac layup? try meandering down the slope so the tyre doesn't track the natural lay of the tarmac. Again, cheap to fix.
Headset too loose; remember, its the "whole system" so the headset may be amplifying the problem. Putting some very heavy grease in there may dampen the steering enough to do the job. Cheap fix.
Control the wobble by bracing against the top tube. Cheap fix.
Too much input from the rider, over-correcting! let go of the bars...OK, so still keep your hands there but just loosen the grip.
If all else fails either ditch the wheels and try something else..but...the issue will nag you and might return with different wheels.
Finally, get shot of the bike and try something with different geometry/material characteristics.[/quote]

Good advice DHL

I did all those including the quite hard leg brace against the crossbar (got short legs!) and then returned the bike when all other avenues were exhausted.
Honestly, coming down a steep hill where you have to brake hard before the bottom, massive speed wobble and you don't think you're coming out of that except in an ambulance
Litigation point: if you know you've got this problem and go out in a group and your crash causes their crash, you would be liable

AK_jnr

Arse up, chin down, loose grip on the drops, knees resting against top tube. Never had a problem over 50mph on quite a few different bikes touch wood.

mroli

I get speed wobble a lot at just under 40mph on a lot of different bikes. The only consistent factor is me and I've tried to address it (changing body position, hand position, weight distribution, bracing top tube etc). The only thing I can think of is that I'm so aware of it and it is such a problem that I am now self-perpetuating it by tightening up. The most practical step I can think of is not riding at 40mph - problem solved (if somewhat unsatisfactory)....

ps - I was once following Alex Dowsett downhill and as the speed approached 40, he looked back and beckoned me closer. The only thing I could think was that I mustn't smash through the back of a pro rider and he looked very confused as I went backwards!

ugo.santalucia

mroli wrote:

I get speed wobble a lot at just under 40mph on a lot of different bikes.

Crap wheels?

priory

When I bought a 62cm 531 frame audax bike in the early nineties it had speed wobble at 28mph . I put on a luggage rack and that stopped it. subsequently using slime in the tyres or heavier tyres stopped or improved it , or I used a different front wheel. ultimately those wheels wore out and since then no problem that I have noticed, but I would be inclined to back off the speed by sitting up a bit with a knee on the top tube if I felt one coming on. In fact I think this is why I do not feel as safe riding designs that have no top tube .

Jerry185

SmoggySteve wrote:

Jerry185 wrote:

Debeli wrote:

Jerry185 wrote:

Definitely replace. I had a speed wobble on my first bike and never found out the cause (tyre, wheel, frame, headset). Problem continued as the LBS kept saying they thought they had fixed it.
I, too, was at 30+ on a downhill straight when I used the brakes - out of control and on wrong side of road with a car coming up. Somehow, broadsided the bike to a stop. Car driver must have thought I was a loon. That was it for me.
Bike supplier took it back no issues

This is not the best advice I have ever read on a cycling (or any other) forum.

I think it might even be a Mickey-take too subtle for me to have understood....

I am still riding many years later on cycles that have given me moments of horror and terror on 35-40mph descents. In every case there was a tweak or an adjustment or a tightening that I either believed or imagined had cured the issue.

Sometimes it was clear, sometimes I was guessing. But if the geometry is right, the rims are true, the spokes are twangy and the tyres at the right pressure, then ride it - do not return it.

One of the finest feelings on a bicycle is to re-address a fast descent after having had a lane-swapping, chaotic, heart-stopping tank-slapper on it and finding the tweaked and trimmed machine goes down it like a guided missile.

Go home, set it up right, take a deep breath and go again. You know you want to.

Seriously, Debeli? This was a life-changing incident and the last one I would ever do. To have got back on that bike going down hill would have been reckless for me and any other poor b*gger in the way. How can preserving life and limb be 'not the best advice?'

I will back up Debeli on this. You know when, where and how fast the wobble occured. You can go into the same descent with eyes open and be prepared if the wobble begins. No one says you have to go hell for leather and ride dangerously. A speed wobble can happen to anyone at anytime on new or old wheels. Its happened to me on rides I've done countless times before on the same setup. Only for the wobble to never manifest itself again in the same place. I would suggest doing the route again and just watching the speed to see if anything happens. If not then pick up the pace. If I stopped riding every time something unexpected happened I'dnever leave the garage.

Sorry, guys, I'm obviously not communicating very well. My instances of SW were all on the same bike; it happened at 5 mph through to 35+ mph. It happened when the wheel hit a patch of rough tarmac, gust of cross wind or just a tap on the brakes. Apart from the really low speed occurrences, the instances were bone shaking, vision blurring wobbles of such high resonance, I thought a major crash was the only outcome. Which would have been the case had the hill been shorter, had any bend in it or had I not created a broadside stop to a halt. This wasn't a 'there, there, naughty bike!' tap on the crossbar. Bike returned asap as there was a lifetime warranty