1200GS High Speed Weave

[grahamf505]

Hi All

I've been pushing my 2005 GS a bit more recently and have had a couple of scary moments with a high speed weave setting in ;-). The first time it felt like I had a tank slapper coming on with the bars kicking back and forth violently.

OK, admittedly, I was doing circa 90mph+ accelerating out of long sweeping bends and in both cases one of two things were influencing factors:

1) Crossing an undulation in the road surface
2) Changing up from 5th to 6th and rolling on the throttle.

This having happened twice, I've now decided to get myself a steering damper cos I ain't brave enough to handle it on my own.

The popular choice seems to be the Hyperpro jobby complete with mounting kit. What I'm not sure of is whether to go for the standard CSC model or the RSC job. I've never been a fan of steering dampers due to the dead feel you get at low speed. For this reason, the RSC seems a good choice. However, I don't care if I lose some of the low speed feel if the CSC version is better at getting to grips with the problem. Frankly, I'd chuck a lump hammer at it if I thought that would stop it, so if a blunt instrument is the best for the job, I'll go for that rather than have a more progressive tool.

p.s. don't let Reg Moule know what I've been doing on his old bike - he might give me a good talking too!

Thanks in advance for your help.

Cheers

Graham

 

[Deleted account Aberdeen GS]

With or without luggage Graham ?
I guess either way ... that shouldn't happen. Have it inspected by a professional?

 

[tanneman]

With this weave you are talking about. Were you trying to avoid something in the road or trying to run a cheetah over

First things first. Tyre pressures, tyre condition, suspension condition, suspension linkages, steering linkages, swing arm swivel point and final drive bearing play needs to checked before going any further.

To avoid disappointment try doing it from the opposite side and see if the same handling characteristics are displayed. Or try to keep to the posted speed limit here in the UK. The advance bikers are not going to like your lack of discipline in your riding style

 

[SteveJF]

Lots of factors to consider! But in all my experience of 4 valve GSs from 1100 - 1150 - 1200 utter stability under all conditions has consistent. I have never had a moment of instability including levels of naughtiness best not mentioned...
So wear and tear, knackered shocks, worn tyres, weighing of rider (I am on the comfortable side of generous! ) should all be considered, but not a steering damper. I think you could be masking something that needs to be addressed.

Sent from my SM-N910F using Tapatalk

 

[AustinW]

Lots of factors to consider! But in all my experience of 4 valve GSs from 1100 - 1150 - 1200 utter stability under all conditions has consistent. I have never had a moment of instability including levels of naughtiness best not mentioned...
So wear and tear, knackered shocks, worn tyres, weighing of rider (I am on the comfortable side of generous! ) should all be considered, but not a steering damper. I think you could be masking something that needs to be addressed.

Sent from my SM-N910F using Tapatalk

 

[Sgt Bilco]

Reg would want it ridden like that

What is the mileage Graham? My money is on the rear shock being goosed as they generally only last 30-40k. The only other option is tyres so double check pressures and wear.

I've never heard of a GS becoming unstable and needing a damper. Many of us can hustle along at a decent lick and I've never had any issues at any speed loaded or solo.

 

[UturnTony]

Shouldn't require a steering damper. If you are experiencing handling problems as you describe there
must be a problem that needs addressing and fitting a damper is only going to (perhaps) mask it.
I have never had any problem like you describe on any of my three GS's (2006,2007 and currently 2011)
and that includes when i did a few hundred miles at normal speeds with a collapsed rear shock.
Hard to guess at the cause without experiencing the problem but such as tyres can, as Chris says, cause
wobbles. I would also give the front ball joint a check out. It may be worn (i doubt it) or it may be stiff
which could help induce that which you describe.

 

[Bumhead]

Cure the problem ...........NOT the symptom

 

[grahamf505]

Interesting. Thanks for all your replies. To answer some questions:

- tyre pressures correct and plenty of tread on both front and rear - am running Metzeler Tourance
- rear bevel casing bearings and swing arm bearings all fine - I had it apart back end of last year to replace the gearbox UJ gaiter and zero play
- mileage is 55,000 so could be rear shock - piston is not pitted nor are there any leaks and the springing appears to be damping adequately at standstill - i'll tighten up the damping a bit and see what effect this may have
- not gone over the front end checking for play, but nothing feels amiss when riding it
- Since taking ownership at around 48,000 miles, one of the first things I noticed was that it was bit twitchy on the front end at motorway speeds and a slight movement of the bars induced a feeling of slight instability, but then I'd been riding Ducati's beforehand, so effectively riding on rails. Not sure why a worn/failed damper would contribute to this behaviour. History of the bike is rock solid - ask Reg, hence why I was beginning to wonder whether this characteristic (meaning what I refer to the twitchiness) was typical rather than atypical
- think my speedo might be reading 20mph fast at high speeds ;-)

- Interesting that motorworks are selling the hyperpro damper and fitting kits for the GS - any thoughts on this?

Love the bike. Ride 1,000 miles/month on it in all weathers. Road presence is awesome, especially with the spotlights fitted.

Graham

 

[sanensafe]

Could it simply be that you are holding the bars too tightly as you get a bit of a shift on?
Try the same section of road, keep a loose grip on the bars and grip with your knees.

 

[mikeyboy]

Interesting. Thanks for all your replies. To answer some questions:

- tyre pressures correct and plenty of tread on both front and rear - am running Metzeler Tourance
- rear bevel casing bearings and swing arm bearings all fine - I had it apart back end of last year to replace the gearbox UJ gaiter and zero play
- mileage is 55,000 so could be rear shock - piston is not pitted nor are there any leaks and the springing appears to be damping adequately at standstill - i'll tighten up the damping a bit and see what effect this may have
- not gone over the front end checking for play, but nothing feels amiss when riding it
- Since taking ownership at around 48,000 miles, one of the first things I noticed was that it was bit twitchy on the front end at motorway speeds and a slight movement of the bars induced a feeling of slight instability, but then I'd been riding Ducati's beforehand, so effectively riding on rails. Not sure why a worn/failed damper would contribute to this behaviour. History of the bike is rock solid - ask Reg, hence why I was beginning to wonder whether this characteristic (meaning what I refer to the twitchiness) was typical rather than atypical
- think my speedo might be reading 20mph fast at high speeds ;-)

- Interesting that motorworks are selling the hyperpro damper and fitting kits for the GS - any thoughts on this?

Love the bike. Ride 1,000 miles/month on it in all weathers. Road presence is awesome, especially with the spotlights fitted.

Graham

Must be something amiss with the bike,
As others have said,the 1200 is a very stable bike,
I used to regularly run my old one flat out with no issues,.100 mph plus on bumpy B roads still caused no prob.

 

[Steptoe]

Check the front ball joint.

 

[grahamf505]

OK. All good advice - many thanks. Will have a look over it the weekend, in particular the rear damper and front steering/suspension. Have gone up half a turn on the rear damper screw (not shock pre-load) and will see what difference this makes (if anything).

 

[tanneman]

Check the front ball joint.

This and do yourself a favour, rebuild the shocks.

The future is whatever colour you want.

 

[UturnTony]

You mention you have adjusted the rear damping which got me to thinking of the front end damper.
What pre-load is on the front? If it's on a low setting try sending it to the highest so raising the
front which will make it less twitchy. If it's already on high, oh. well.
It's a clutching at straws thing but when you are trying to sort these kinds of things you need to try stuff.

 

[Greenman14]

Just because the shocks aren't leaking and look ok doesn't mean they are working and giving the damping they should. As already said anything ove 30k miles and they will be well past their best, and even their best was not great compared with decent aftermarket shocks.

 

[Skid06]

2008 me and my brother bought new GSA's with ESA on the same day, mine weaved his didn't, happened at 90-95mph with luggage and got worse with more speed, dangerous even, when i rode his bike it did feel like it had more ride height in the front and was rock steady at any speed, it only happened loaded with luggage

 

[Pauly S]

my 1150 gets a wiggle on about 110 with two wardrobes affixed. no great surprise really.just back off and go slower.

 

[tuftywhite]

Must be something amiss with the bike,
As others have said,the 1200 is a very stable bike,
I used to regularly run my old one flat out with no issues,.100 mph plus on bumpy B roads still caused no prob.

Now you tell me!

 

[Sgt Bilco]

Check the front ball joint.

Steptoe may well have hit mark with this.

I had a front ball joint issue last year where the bike seemed to have a mind of it's own and weave. On long straight roads, if you let go of the bars go it would quite violently dip one way, I'd centre the bike up let them go and it would dip the other. With both hands on the bars I would be correctling this oscillation all the time and it was vey uncomfortable and actually mede me feel sea sick. With 2000 miles through Alaska to go it need to be sorted. I have to say it sored itself after much poking, pulling and tightening. On inspection later on, there was a slight split in the rubber and we think dirt found it's way in there after a day from hell on a the Top of the World Highway which was like a river of mud and shite.

New gaitor and it's never happened since but worth a look at.