What causes a speed wobble (high speed weave)

[stevecbr]

Had new tyres fitted tuesday, BT023's to my MT09.
Rode fine tuesday, did about 70 miles scrubbing in tyres, didnt go that quick.
Took it out wednesday, rode about 50 miles, but couldnt get much over 100 as bike started to weave.
It was very windy, so not sure if that could be the cause on a naked bike.
Wasnt able to tell today, due to pouring with rain.
Just wondered if anyone experienced similar with naked bikes, or do I need take a trip back to tyre fitters
Nothing else changed on bike, tyres are correct pressures, everything looks tightened up, new balance weights were fitted and are still stuck on, bike is only 6 months old so not likely to be worn bearings.

 

[marcusfordus]

Rear wheel alignment could be out a touch, or it wasn't quite zeroed on a static balance maybe 5 gramms out.
Unless you were right 1st time with the wind thing.

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[stevecbr]

Wheel alignment looks ok, they didnt fiddle with anything, just wheel out, wheel in, I watched them throughout.
It is worth checking the rear is straight I suppose, no doubt the adjuster marks are not correct

 

[marcusfordus]

Funny ole things rear wheels affecting the front. Just getting the torque wrong when tightening the axle nut can throw the alignment out.
I'd slacken off the nut, make sure the wheel is pushed fully tight up against the adjusters and re torque. Just to eliminate one possible issue Steve.

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[razz]

Had new tyres fitted tuesday, BT023's to my MT09.
Rode fine tuesday, did about 70 miles scrubbing in tyres, didnt go that quick.
Took it out wednesday, rode about 50 miles, but couldnt get much over 100 as bike started to weave.
It was very windy, so not sure if that could be the cause on a naked bike.
Wasnt able to tell today, due to pouring with rain.
Just wondered if anyone experienced similar with naked bikes, or do I need take a trip back to tyre fitters
Nothing else changed on bike, tyres are correct pressures, everything looks tightened up, new balance weights were fitted and are still stuck on, bike is only 6 months old so not likely to be worn bearings.

hello there , i did get a weave or three while i was running mine in , i adjusted the rear shock , ( stiffer ) and that helped me , with mine , i thought that when at full chat n leaning back as i do with a full rucksack , it was making the front end light , the fz8 used to weave loads till i dropped the forks in the clamps , just a thought

 

[THAIGATE14]

jackets can play a part in getting a weve on, my rocket jacket is a bit baggy under the arms and gets me a bit wiggly around 150kph but my triumph jacket is a good tight fit and is fine at high speed.

 

[Fish1216]

I had the exact same problem, had new metzeler m7 rr tyres fitted, after about 80 miles I started riding a bit faster and noticed between 105 and 115mph it had a high speed weave then disapeared up to about 125 but slowing back down it did the same thing, I checked my tyre pressures and they were a bit low, checked head bearings and wheel weights and they were fine, but it was windy and I did notice my jacket flapping in the wind when looking in the mirrors, tried it since with no wind and its fine now, I put it down to my jacket flapping about and slightly low tyre pressures

 

[stevecbr]

Checked wheel alignment and its out a fair bit, most of if due to the shit alloy adjusters that deform when tightened. Will take it for a spin after tea, and hopefully be ok. According to alignment marks its now well out, but by my reckoning it should now be spot on


View attachment 1798

 

[stevecbr]

Still there, spoke to tyre fitter, will be taking it back to be checked next week, he is unsure what could cause it.
picture of adjuster block

 

[Triple Trouble]

My adjuster is in exactly the same state..!

 

[THAIGATE14]

Still there, spoke to tyre fitter, will be taking it back to be checked next week, he is unsure what could cause it.
picture of adjuster block
View attachment 1800

it because the area of the block the bolts locks against is only 2mm deep. it needs to be 6mm or more to prevent deformation when the bolt is turned against it.

 

[marcusfordus]

Poorly designed and not up to the job springs to mind. Worldwide too, reading the comments and seeing the pictures.

It'll change on the MK2 version if enough complaints are filtered through to Yamaha.

You could buy the "other" Yamaha version which is what they want you to do anyway with their extortionate pricing. I'll machine my own when I get around to it.

 

[flydnb]

that's a warranty issue surely as that block is not fit for purpose.

 

[UnluckySlats]

You would like to think so

 

[Partridge]

I have just had mine replaced under warranty. However it is exactly the same and has already started to deform
Back to the dealer we go

 

[flydnb]

they should put those giles blocks in really..

 

[razz]

Just checked mine , and it's a tad rough too , and I have not been near it , will have a chat with Tinklers n see what they say , these look ok , LighTech Motorcycle Race Parts - UK ONLINE STORE - Rearsets,Levers,Paddock Stands,Pitlane Equipment,Clip ons

 

[stevecbr]

£150 for chain adjusters!!
LighTech Yamaha MT-09 13-14 Chain Adjuster Kit

 

[Triple Trouble]

I've just ordered some of the Gilles ones off the bay...!!

 

[Kinjane]

£150?

Just over £190 with vat and delivery !!!!

Presumably this is included in the price...
http://www.lightechuk.com/ekmps/sho...ghtech-performance-parts-lightechuk.com-5.jpg