Tyres, Brakes and Suspension » 100MPH JACKHAMMER

Bought my r1200rs with bent forks and subsequently bent the front axle in a pothole.Fork and axle and wheelbearings replaced, wheel and tyre balanced with no visible runout.
Rides beautifully up to 160 kph, then handlebars start to vibrate like a jackhammer - doesn't improve going faster ( tried to 180 before nerve gave in).
Is it possible that there is tyre damage internally that only comes into play after a certain speed?

Zitat von Big Al im Beitrag #1

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Bought my r1200rs with bent forks and subsequently bent the front axle in a pothole.Fork and axle and wheelbearings replaced, wheel and tyre balanced with no visible runout.
Rides beautifully up to 160 kph, then handlebars start to vibrate like a jackhammer - doesn't improve going faster ( tried to 180 before nerve gave in).
Is it possible that there is tyre damage internally that only comes into play after a certain speed?

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Are you sure the frame is straight?
Were the forks installed properly (not tweaked when everything was tightened up)? There is a specific procedure to follow.
Those are the things that spring to mind off hand. Brakes were mentioned- you would feel a warped rotor pulsing when you used the brake at almost any speed.

At 160 kph, you are probably turning ~7K rpm (you can verify). Try running up to that high rpm's in a lower gear and speed to see if the vibration is from the engine.

Thanks for all the suggestions. Tried the brakes and engine speed suggestions-no help.Then had local dealer fit and balance an old tyre they had lying around.Magic.No vibes (at least to 220 ,when I ran out of clear road and into traffic (:-))
Interesting that the defective tyre had NO external signs of damage or run-out and balanced perfectly.
Probably logical that a pothole that bends an axle will damage a tyre as well........

Good to hear that a rebuilt bike with bent forks, suspect frame, rebuilt wheels and duff tyres is still good at 160 kph but with a balanced old tyre OK up to 220kph. This guy has some serious appendages! 😱

Thanks, but according to my better half I'm just incredibly stupid.
But truly, South Africa is biking heaven (apart from random potholes). Between Cape Town and JHB one gets literally 100's of Km (60's of miles?) of open road virtually unpoliced. Bikes seem to shed number plates on leaving town and the cameras become insignificant. Oh, and the weather is almost always good.
Still thanks again for all the suggestions

It is nice to hear resolution on bike issues. Thanks for letting everyone know. And that's a pretty good fix! No new parts involved.
I wonder if hitting the pothole tore some of the internal mesh or structural cords?

Convinced that's what happened. There were two transverse lines inside the tyre, not tears through the rubber , which didn't appear to have any construction or manufacture basis. Ah well, all's well that ends well.