Speed Wobble

[The Saint]

I am finding on a regular basis these days whilst decending at anything between 40 and 60km's I am starting to get a speed wobble and have almost fallen last week Saturday and this week Sunday in the H2H. I do however think they should have put a rubber mat over the speed restrictor bumps on Klipriver road which caused me to get my wobble, almost fall off and then almost get hit by the car behind me as I had to go into the right hand lane whilst trying to control the wobble to avoid the fall. But even without the bumps this tends to happen on a regular basis to me. I can however ride comfortably on a flat road doing these speeds with no problem. I now find myself riding the brakes downhill in order to avoid this and watching my mates disappear into the distance.

 

Should your weight be transferred onto the front wheel when decending in order to avoid the wobble or what else would cause this?

 

Any tips?

[David #7]

Check that your headset is not loose.

[The Saint]

Good point, recently replaced a stem although it does not feel loose but I will get a bike mechanic to check it out...thanks

[Thyolo]

Hi Mux,

 

I reckon I'm a middling cyclist and know what it's like to be uncomfortable going fast.

 

With the wobble I s'pose it has to be you or the bike and it's probably not the bike as something would have fallen off by now or made a loud noise if it was that defective as to give a pronounced wobble.

 

I'd check to see if how tense you are, if you're expecting a wobble, chances are you stiffen up and it's self-fulfilling.  Balance and nerves work in opposite directions.

 

Anything over 55 and I come off the drops onto the hoods, still crouched, but I don't feel stable in the lower position - there's more leverage for the bars to move around so I come out of it.

 

If you're relaxed on the hill you mention, 80 even with the bumps is fun because it's smooth and wide.

 

So my 2cs is to say be aware of how you're feeling and slowly work your confidence up by increasing speed on downhills for shortish periods, then coming back to where you're comfortable.

 

I find thoughts of crashing a pain but they get easier with time (and no crashes!).

 

You could also check that your wheels are not banana-shaped.

 

Good luck

[Vincent]

Also check wether there is not a deformaty in the vasinity of your valve- If so- deflate the tube and push the valve inwords, and re- inflate.

[Cois]

I had the same problem. I was scared to crap on a mountain pass. Went down with my mtb at speeds of 70 km/h. I went down there with a road bike few days later, and could not control the bike down there.

 

I think its all in the mind.

[The Saint]

Going to go with the mind theory as I have only been having this problem since a fall on a downhill where my wife tried to jump onto my bike and I broke my wrist. Next downhill will be balls to the wall.

 

Thanks all, I will let you know how it goes if I survive.

[Cois]

good luck!

[linnega]

For there to be a wobble, you only need a slightly loose headset or hub, or slightly misaligned frame.  At high speed the wobble is amplified until it makes you uncomfortable.  Even when it is really uncomfortable, it is unlikely to make you fall.  Do check your headset and hubs - just hold your wheel with your knees and see how much play there is.  If you start to get a speed wobble clamp your top tube with your knees and that should solve the problem.  If that doesn't solve your problem then something is definitely loose and I would guess headset.

 

[AndreZA]

What frame do you have? I've heard the alu Giants, especially the aero ones, can cause wobbles.

 

 

[Gravity Sucks]

A technique used to come out of the wobble is to pinch the top tube with your knees ie. If your knees face outwards the centre of gravity is all over the show. Bring the knees inwards and the centre of gravity is more centred and stable. Saved me from falling a few weeks ago doing 80km

[Brakkies Sport Fotos]

Do you ride a carbon Giant ?

 

 

 

If yes, it will wobble at 65km/h +

 

 

 

Sit back on the saddle and put you kneee's against the top tube. It stabilize the frame on high speed. Good luck, but be aware, that if you sit back, it will stop wobble, but the front wheel CAN SWERVE over the road.

[bikemonster]

Do you ride a carbon Giant ?

If yes' date=' it will wobble at 65km/h +

Sit back on the saddle and put you kneee's against the top tube. It stabilize the frame on high speed. Good luck, but be aware, that if you sit back, it will stop wobble, but the front wheel CAN SWERVE over the road. [/quote']

 

Great!

 

So when you go over into the oncoming traffic you will do so in a smooth, graceful arc, rather than wobbling like a jelly.

 

Style is everything.

[TNT1]

 

I was scared to crap on a mountain pass.

 

Why? Were there people watching, or did you run out of toilet paper?

 

[Giant]

I have a carbon Giant, and descend like a loon, no wobble,Infact I regularly decend in the high 50's without holding the bars.

what I will say is do not put more weight forward if you are wobbling, that will put more weight on your arms, which in tern stifferns them, which will amplify the wobble, get your weight back and lighten your grip.

[Thyolo]

a fall on a downhill where my wife tried to jump onto my bike and I broke my wrist.

 

???????????

 

Was she overcome with your sporting prowess that she had to make that leap, or what?

 

We need the video of this, or at least a diagram.