Help ! getting to the end of my tether with front end shimmy

[smartr]

Hi All,

I posted a thread on this a couple of months ago and BMW have still not solved the issue so here's the story so far.

I have been experiencing a front end shimmy through the bars at around 40 mph. This then delvelops into lots of vibes through the foot pegs and bars at higher speeds.. really annoying !!

The problem only arose when I changed tyres from Anakees to Trail Attacks. I dumped the Trail Attacks after only 1000 miles thinking that was the problem. I changed them for Tourances and whilst having them fitted the tryre fitter noticed the rear wheel was buckled. I therefore assumed this was the cause.....

Off to BMW (Coopers Tonbridge) who confirmed the buckle and replaced the rear wheel under warranty.

No Change ! still the same shimmy so back to BMW

They then told me the final drive is knackered (how they missed that when the wheel was replaced god only knows) so that was replaced under warranty as well

No Change still the same shimmy !! so back to BMW

They now try and tell me it must be wheel balancing and it's the tryre fitters fault (even though BMW balanced the new rear wheel themselves!!) so send me back there with the exact BMW spec for balancing the wheels. Tyre fitter follows the spec exactly and guess what..

No Change still the same shimmy.

The Bikes going back to BMW next week and I have told them I don't want it back until they sort the problem out.

It's an '07 GSA with 19,000 miles covered in 16 months.

I can't fault the dealers handling of the warranty work but this is the 2nd GS I've owned it it may be the last if this problem persists. I'm assured by the dealer they road test the bike after each service or warranty replacement but it is clear they do not because the vibration is very pronounced.

Are there any similar experiences out there or suggestions as to what else it could be??

any feedback will be much appreciated before I blow a fuse myself and go Japanese!!

 

[st247]

I have been experiencing a front end shimmy through the bars at around 40 mph. This then delvelops into lots of vibes through the foot pegs and bars at higher speeds.. really annoying !!


Are there any similar experiences out there or suggestions as to what else it could be??

You might have more luck on ADVrider. Here's a similar problem

 

[(RIP) Kaister]

it all points to the front tyre - really

put 50psi in it and see if it cures it - then you'll know for sure ( removes any imperfections in carcass strength and integrity )

 

[Shep]

Does engine speed make any difference

ie Does it still shake at 40 in 2nd 3rd 4th etc? With no change to the vibration pattern?


Does the vibration still occur when cornering and is it the same in both left and right corners? On throttle off throttle?

Shep

 

[Wapping]

I had a similar problem.

http://www.ukgser.com/forums/showthread.php?t=119143&highlight=dunlop

 

[Nobbyk]

I know it's a bit of a trek from Kent, but Darren at MCT in Stowmarket, Cambs, may be able to shed some light. He has looked after my bikes fore the last 5 years with regard to Suspension.

I believe your problem might be conected and I would certainly reccomend him to have a damn fine go at sorting it, or pointing you in the right direction. He's done many GS's and knows them pretty well, he's also a demon rider being an ex endurance racer

Give him a call

01449-777161

Nobby

 

[smartr]

Does engine speed make any difference

ie Does it still shake at 40 in 2nd 3rd 4th etc? With no change to the vibration pattern?


Does the vibration still occur when cornering and is it the same in both left and right corners? On throttle off throttle?

Shep

yep the shimmy is there in any gear at 40 it's also there when going round either right of left bends and with Thotle on or off.

I've tried different tyre pressures and that seems to make little difference. Just can't understand it. Can't believe that both the Trails Attacks I fitted or the replacement Tourences are faulty, seems to much of a coincidence.

I don't want to go back to the Anakee's as I've already wasted 200 quid changing from a new set of Trail Attacks and anyway all these tyres are standard spec for the bike.

 

[mr badger]

Darren at MCT in Stowmarket, Cambs, may be able to shed some light.
Give him a call

01449-777161

Nobby

Indeed. Genius at transforming handing. Just had our 3rd bike sorted there as well as work for friends.

 

[Womble]

I know it's a bit of a trek from Kent, but Darren at MCT in Stowmarket, Cambs, may be able to shed some light. He has looked after my bikes fore the last 5 years with regard to Suspension.

Stowmarket's not in Cambridgeshire, it's actually well into Suffolk, which is good news if you're coming from Kent. It's about 20 minutes along the A14, from the top of the A12 at Ipswich.

And I can vouch for his skills, he turned a bike that was handling like a total dog into something that felt brand new.

 

[davedyer]

The problem only arose when I changed tyres from Anakees to Trail Attacks.

I think that's your answer.

I don't want to go back to the Anakee's as I've already wasted 200 quid changing from a new set of Trail Attacks and anyway all these tyres are standard spec for the bike.

I think you'll have to simply to confirm or otherwise that that's the cause.

 

[Rushy]

I think that's your answer.



I think you'll have to simply to confirm or otherwise that that's the cause.

Nope 'cos he says its doing it on Tourances too

 

[JohnnyBoxer]

More PSI in front tyre

 

[smartr]

I think that's your answer.



I think you'll have to simply to confirm or otherwise that that's the cause.

I guess you're right Dave but I'm going to see what the dealer says first before wasting even more money

I might try the earlier suggestion of putting 50 psi in the tyre first so see if it makes a difference, at least that might rule out a faulty tyre.

 

[JohnnyBoxer]

I might try the earlier suggestion of putting 50 psi in the tyre first so see if it makes a difference, at least that might rule out a faulty tyre.

That should help, try 40 & 45 PSi, worked for me when I've the dodgy front Tourance syndrome on a few occasions

No marked effect on handling either when I did it

 

[GSmonkey]

Tourance's do have a dodgy front. I thought I was going to come off the first time I put on a new set of Tourances. Never had the same problem with anakees.

 

[Gabby]

Funny that....I get a similar Shimmy at 125mph.

Can anyone explain that?

 

[Radar_UK]

Tourance's do have a dodgy front. I thought I was going to come off the first time I put on a new set of Tourances. Never had the same problem with anakees.

How do you mean a dodgy front ? I've just switched to a set of Tourances from Sahara 3's and find the front doesn't feel right regardless of what pressure I use - bike was perfect before I changed tyres !

 

[Fanum]

How do you mean a dodgy front ? I've just switched to a set of Tourances from Sahara 3's and find the front doesn't feel right regardless of what pressure I use - bike was perfect before I changed tyres !

Can you define 'Doesn't feel right'?

Tourences will feel totally different to Sahara 3's......they will turn in quicker, the profile making it feel like the bike is actually dropping into the corner.

It may be just a case of getting used to them.



Smartr...If I were you, I'd ask a mate, or the dealer, to swap out a front wheel for a test ride for you....idealy with a worn in, different tyre altogether on it (one off a demo bike would be ideal)

This may at least exclude the front tyre (which I agree it sounds to be)

There was a batch of tourences that were known to be faulty but that was a long while ago..I 'spose it is possible that you may have been supplied with an old stock tyre and then been unlucky....it's going to happen even though it may be a one in a million chance

 

[Radar_UK]

Can you define 'Doesn't feel right'?

Tourences will feel totally different to Sahara 3's......they will turn in quicker, the profile making it feel like the bike is actually dropping into the corner.

It may be just a case of getting used to them.

When I run them at recommended pressures (30/33) they feel very soft/squidgy almost like a semi flat - not a 'nice' feel at all, tried them at 35/40 and it feels better but harder to turn in and still not feeling as nice as the Sahara's.

Have to agree they turn in much quicker at 30/33 than the Sahara's ever did - you could be right in that I just need to give them some more time.... How many mile till they are properly scrubbed in ?

 

[Fanum]

When I run them at recommended pressures (30/33) they feel very soft/squidgy almost like a semi flat - not a 'nice' feel at all, tried them at 35/40 and it feels better but harder to turn in and still not feeling as nice as the Sahara's.

Have to agree they turn in much quicker at 30/33 than the Sahara's ever did - you could be right in that I just need to give them some more time.... How many mile till they are properly scrubbed in ?

Several years since I used Tourances, I use TKC's all year on and off road I'm afraid, but it's not really a case of getting scrubbed in, although they will wear to your usage pattern IYSWIM....

The carcass itself is shaped....the profile of the Sahara is more rounded, almost pear shaped in fact, so the turn in feels consistent and smooth, whereas the tourence is rather more 'v' shaped and hence it feels like it dips into the corner...the plus side being you get more rubber contact patch.

Even when it's well squared off on motorways, it'll still feel different.

It's one of the reasons that I prefer the TKC's TBH.