My SDR has developed a wobble

Ok - so my 2007 SDR has always been rock solid in a straight line and on corners.

Its currently on the standard settings as per the manual and has done 12000 km. Tyre pressures are 34 front 36 Rear.

Wednesday is our normal midweek blast about 250 km after work - home by dark. Same route we always take.

Just this last wednesday my bike started to develop an unsettling little head wobble. In fast sweepers [160km/hr] the front seems to feel quite light and it waggles [?] a bit from side to side - quite lazily.

I was interested to see what you guys thought the problem might be? All the sports bike riders I was with were just dismissing it as a 'handlebar' bike problem - but its always felt so planted in the past - I have never had any headshake at all? I hold on with my knees and I don't swing on the bars by the way.

I wound the damper up a bit but its still there.

I have some theories but I wanted to see what you all thought it might be without cluttering the conversation up with prejudice...

What should I be checking, looking at?

How worn are your tyres ?

Could be as simple as that...

Other than that I would check everything on the front end including head bearing play etc

Also worth double checking all your suspension settings.

Check wheel bearings (that's front and rear)- you might have to take the calipers off and lift the front off the ground to do this.
Check the headstock bearings for any movement.
I doubt there's any play in the forks, but a tug or two should figure that out.

But before any of that, check both your tyres, all the way round, and re-check the tyre pressures. Check that the wheels are within balance as you might simply have lost a weight or two from the rims.

And also, check the swing arm for any free play.... Finally.. check that your wheels are round! That should cover most of it...

If it's developed a wobble, it's got a problem. As simple as that. Vibrations transplant in funny ways.

I had a rear wheel that was out of balance and I could have sworn that it was something really serious with the front of the bike.

Thanks for all your comments - there is some confirmation in there of what I was thinking.


Standby for a photo for you comment...

OK so my guess was tyre.

Checked bearings in wheels and wheel weights - no probs.

Checked suspension settings - all normal [did wonder at 12k whether fork oil might being going off? But it shouldn't make that much difference straight away unless I had a leak - which I don't]

Tyres - Check this out!




This has to be the issue right? I have never had a tyre do this? Next question is what the hell is going on here? The front of the tread has worn off to the point where the tread block is lifting? The back of the tread block seems to be wearing normally? Crap tyre? Bad suspension setting? Bad riding? Wrong pressure?

Yes its a Corsa III - this is the first Corsa III I have used - I have run the older standard Corsa and not had this problem.

Tyre is definitely toast - going to get some BT-016's even though the front has plenty of life the corsa's are the most expensive tyre by a long way here and I won't be going there again - not worth it. The 016's have been brilliant on my 690.

Thanks for the reading on cold tearing - I will get the new hoops and and see if my dealer [who is a racer] will do me a suspension set up.

Bodge, if that was a rear Corsa III, then yes, there's a certain condition that they just don't seem to be able to handle. If I'd have to make a guess, my guess would be that it's the combination of three things;
1) Aggressive riding
2) Higher than necessary tyre pressures
3) Too stiff suspension settings, especially rebound.
If one of these aren't filled, it won't happen (as badly). The tearing seem to start between the two different compbounds.

If you, don't meet the three criterias above, especially if you've got it all set up, the Corsa III can be quite a good tyre. I seem to prefer the Sportec M3, which is very similar, over the Corsa III.
Here's a pic of my Corsa III after about a season on the 'Ring.

As you can see the wear is nice, but to get here the suspension set up is quite soft, and the pressures are probably between 30-32psi (on a behemoth like the K1200R), and I let the tyres warm up for quite a while before I start playing "properly".
But still, despite all these factors, you can see the transition between the soft shoulder compound and the harder centre compound.

Methinks BT-016 are going on my SDR when the OEM Corsa III are worn out...
It would be interesting to hear what your dealer/racer fella has to say about the issue. Keep us posted.

if its lifting up i would say cold tear. usually high-speed rear end wobble in turns is the rear suspension being set up improper. its probably chicken or egg at this point. did the tyre cause the wobble, or did the suspension cause the tyre

From the looks of your tyres that is definitely a suspension problem. Mine did not wobble but my tyres wore like that until I had mine set up by Suspension Specialist, Inc. I don't know the extent of your dealers suspension skills but I know there are suspension shops in my area or at any track day program that will set it up for your weight and riding style.