Weaving

[craig614]

Went out for a spin tonight and every time I came across an HGV (or big truck thing) the bike would go into a weave. It was very noticeable and a bit scary - my initial thought is to do with the screen. Anyone come across this before?
Thanks

 

[Macp]

Went out for a spin tonight and every time I came across an HGV (or big truck thing) the bike would go into a weave. It was very noticeable and a bit scary - my initial thought is to do with the screen. Anyone come across this before?
Thanks

I have noticed this on my ADV but it was a windy day. Just backed off a little out of his slipstream then all ok. Blasted past as soon as I could.

 

[pragmatix]

Check your tyre pressures.

Pete A

 

[GSmonkey]

I get this as well, first thing I noticed when I took the GS out onto the motorway.

I find the problem is worse when having the top box mounted on the luggage rack - moving to pillion makes it better.

 

[Shep]

Yep, same here

I find the bike starts to feel unstable in fast traffic/behind lorries etc, but if I adjust my sitting position (generally leaning forward slightly without increasing my grip on the bars seems to sort it out, or if I put a bit more weight on the footpegs sometimes improves things but this can get tiring after a few miles)

Generally I feel the bike is stable but the wind/buffeting seems to affect my upper body, has anybody with an aftermarket screen found it makes any difference?

Regards Shep

 

[Tobers]

The easiest way to solve this is to wind up the rear preload somewhat. The bike is quite low at the back so the front is quite light. This means it is quite sensitive to uneven airflow from behind lorries etc, causing the weave you mention.

It is worse if you have weight on the back as well.

I noticed a mild weave at 80-90mph on mine but didn't think much about it until I went on a trip with a heavyish bag strapped to the back. The front felt v.light and th eweave was worse, triggering my thoughts that the rear was too soft. A quick twiddle with the preload solved it.

Try it & see. Nothing to lose - you can always wind it back again.

 

[Rich]

I certainly notice it upwards of 70, but it gets less noticebale the faster you go IMO

I think this is what the US chaps call squirelly (how do you spell squirel...hmmmm).

I just relax and dont grip the bars too tight and live with it, although altering the suspension setup Im sure would sort it. as Tobers says.

 

[wilbjr21]

I just look on this a fact of riding - happened on all of my bikes from Honda ST1300 to Aprilia RSVR. Another good reason (along with the the visibility issue) to pass as quickly as possible. No worse than I would expect on my R1200GS.

 

[Mr K]

The slipstream is buffeting you.
You are hanging onto the 'bars of your bike and so the buffeting becomes steering input.

Don't believe me? Next time it happens crouch-down out of the wind-blast.

 

[GSmonkey]

It is worse if you have weight on the back as well.

That's probably why moving the box to the pillion helped, as it put more weight on the front.

Also explains why you don't get any similar effect with sportsbikes, as there is much more weight on the front.

So dropping the pre-load on the front should have the same effect as jacking the back up, I would guess.

 

[jlabro]

it happens to me too !
it's all in aerodynamics i guess,can not change it !!

it should happening because the airflow is very different when you get behind a long and high vehicle

 

[birdseye]

Not sure its an aerodynamic effect. Seems to me that what is happening is that the wind buffets you around the shoulders, pulls your arms and hence the steering - because the steering is light and the bars are wide. When this happens you naturally tighten your grip and the problem gets worse. If you relax your grip or duck down behind the screen, the bike carries straight on. Gets better if you acccelerate hard too.

Another confirmation of this is that the bike is very little affected by cross winds. Where I live near the Severn bridges, cross winds are a real prob crossing the river. On my previous Pan I was often reduced to 40 mph in a national speed limit, and still had buttock clenching moments. On the GS - no problem at all.

 

[Tobers]

Try the suspension adjustment thing, and then visit Nippy Norman's to get some most excellent Tobinators to adjust the screen more to reduce the buffeting.

 

[Mr K]

Not sure its an aerodynamic effect. Seems to me that what is happening is that the wind buffets you around the shoulders, pulls your arms and hence the steering - because the steering is light and the bars are wide. When this happens you naturally tighten your grip and the problem gets worse. If you relax your grip or duck down behind the screen, the bike carries straight on. Gets better if you acccelerate hard too.

Another confirmation of this is that the bike is very little affected by cross winds. Where I live near the Severn bridges, cross winds are a real prob crossing the river. On my previous Pan I was often reduced to 40 mph in a national speed limit, and still had buttock clenching moments. On the GS - no problem at all.

I said that