GS1000 weaves on concrete rain grooves

[srsupertrap]

Here in Colorado we have lots of stretches of concrete highways with deep machined rain grooves which make my GS1000E feel like it has a hinge in the middle when riding on them. The oscillation can be felt throught the handlebars, moves the GS side to side and frankly sucks. Once I get off the concrete section and back onto good old asphalt all symptoms disappear?

Within the last 2 years I have replaced the rear tire with a Avon AM26, installed new rear wheel bearings, loosened & retorqued the swing arm pivot nut, loosened the steering stem bearings, adjusted & retorqued. The steering stem bearings shouldn't be damaged because they are Timken's and I don't wheelie it. I have loosened all the front fork & axle pinch bolts, bounced & compressed the front end and carefully retorqued all the bolts in the proper sequence per the Red Factory Manual. The tires are properly inflated etc and still the weave persists. That narrows it down to perhaps the front tire which is currently an old Metzeler ME33 100 90V-19 or perhaps the swing arm bearings? The Metzeler ME 33 front tire is not cupped and although it's not an Avon they work fine together on regular asphalt. The swing arm is not stock, it's a CalFab street swingarm. I did not remove the swinger when I replaced the Avon rear tire. If I recall the CalFab swinger has needle roller bearings, I greased them xtra good when I installed it but that was 25 years ago and 35K in the rear view. The GS has not been subject to sitting outside or rain etc.

Could the weave not be mechanically related? I mounted a Shoei FM2 fairing when the GS was new I had the same weave at higher speeds with the stock swingarm etc. Very curious whether other CO. GSers experience the same symptom on 287? Never replaced swing arm bearings, but I guess you just use a drift pin? Hope those CalFab bearings are the same size as OEM.

[doctorgonzo]

There may be things that will make it "better", but every bike I've ever ridden felt like you were on ice when riding on grooved concrete.

[simon kuether]

Mine does something like that when the tyre pressures drop a couple of psi . ????? Cheers , Simon.

[Steve]

OK your front tire looks like this:


That groove around the middle is what does the tracking of the grooves.

Older tires that looked like this were even worse:


I have had Dunlop E3s on my Wing for many, many thousands of miles, and have recently switched to Michelin Pilot GTs, but the tread pattern is similar in that there are NO grooves that follow the circumference of the tire:



To give you an idea of the stability of such a tire, here is a short video that I shot while going traveling on a metal grate, across the Mackinac Bridge into the Upper Peninusula of Michigan. This was on the Dunlops, speed was about 45mph, cruise control was on, left hand on the handlebar, right hand holding the camera. Oh, I was towing a trailer too. There was no wandering across the metal grate, which was good, because there is over a mile of it to travel. Although there is a right lane with solid pavement, it was closed for bridge maintenance.


As I panned down, you can see the bridge supports and the water below.

[Nessism]

I've found that those Avons like to follow the rain grooves. Nice tires but not perfect. Of course it's mostly the front that cause the wandering so not sure how much this comment relates to the issue at hand.

[twr1776]

Have you upgraded the front with Progressives and/or replaced & checked you wheel bearings?

I agree with both Steve & Ed, I am currently running a set of each and the Dunlops do the least "tracking" and the Avons do some "tracking" but both are light years better than the tires with the center groove. I am not sure if any tire will not tend to track on parallel grooves since the tire is 'searching" for a line.

[chuck hahn]

Our roads her in MI have the same grooves..I am meticulous about my bikes and upkeep etc. EVERY BIKE I OWN BEHAVES HE SAME WAY ON THAT SURFACE ( See the list). This is much to do with nothing..its just the sqwiggles in the surface "PULL".. same thing with the grated surfaces on suspension bridges like when i drive over the Mackinaw Bridge.. same thing. If you are sure everything is in order..steering bearings, wheel bearings, tire pressure, no calipers dragging,etc,etc..then i would suggest that it has nothing at all to do with your bike.You can change all the tires you want and scare the hell out of yourself and it all will boil down to the fact that those grooves and grates just will push and pull a bit.

[doctorgonzo]

The sport demons have a center groove, but it's like a wave not straight.

[posplayr]

Assuming you dont have other issues, with wider radial tires it all goes away

My ED with 18" GSXR 3 spokes doesn't do it anymore. Currently running a Pirelli Strada (110/80-18 on 18x2.75" rim )and Dunlop Roadsmart (170/60-18 on 45.x18" rim)

[bonanzadave]

loosened the steering stem bearings, adjusted & retorqued. I have loosened all the front fork & axle pinch bolts, bounced & compressed the front end and carefully retorqued all the bolts in the proper sequence per the Red Factory Manual.

Just curious.... Does the manual tell you to tighten up the steering head nut with the fork pinch bolts loose ? I dont believe it would do anything unless the top or bottom fork bolts are loose.

Another vote here for front tire.

[gshub]

weave and wobble

Mine does something like that when the tyre pressures drop a couple of psi . ????? Cheers , Simon.

cant think the metz would cause it to weave maybe tyre preasures had metz me33s on
all my bikes,my Gs1000s has them tried to make it weave and its rock solid ,alot
of weaves is down to body weight now im alot older nearly Big 50 next yr and 15stone,when
20ish and only 11stone my Gs1000e used to weave terrible frightning some times.
But having said that I dont like concrete roads especialy when its raining.

[bwringer]

Why does this freak people out so much? It's a total non-issue.

So the bike wiggles around a little on surface grooves. So flippin' what? It's meaningless. It doesn't feel anything at all like a loss of traction. So why all the whining?

It's just a very common complaint that I've never quite understood.

[srsupertrap]

Steve,
I never made the connection that the tire center groove would be causing my weaving problems. Now when I think about it, when I rode the same stretch on the Honda ST1100 shod with ME Z4's (which have a similar pattern to the Pilot's) it never weaved at all. I never used a pair of those old Conti K112's but they sure were popular with the BMW air heads and later the Harley boys in the 80's. BTW cool video you got more balls than me shooting that video; I hate those grated bridges when you look down. Thanks for the information.

Steve

That groove around the middle is what does the tracking of the grooves.

Older tires that looked like this were even worse:


I have had Dunlop E3s on my Wing for many, many thousands of miles, and have recently switched to Michelin Pilot GTs, but the tread pattern is similar in that there are NO grooves that follow the circumference of the tire:



To give you an idea of the stability of such a tire, here is a short video that I shot while going traveling on a metal grate, across the Mackinac Bridge into the Upper Peninusula of Michigan. This was on the Dunlops, speed was about 45mph, cruise control was on, left hand on the handlebar, right hand holding the camera. Oh, I was towing a trailer too. There was no wandering across the metal grate, which was good, because there is over a mile of it to travel. Although there is a right lane with solid pavement, it was closed for bridge maintenance.


As I panned down, you can see the bridge supports and the water below.

[srsupertrap]

Up front I have Progressive fork springs installed with the PVC spacers and 15 wt fork oil. Still running the original wheel bearings but they will be replaced when I replace the tires or switch over wheels . . .

Have you upgraded the front with Progressives and/or replaced & checked you wheel bearings?

I agree with both Steve & Ed, I am currently running a set of each and the Dunlops do the least "tracking" and the Avons do some "tracking" but both are light years better than the tires with the center groove. I am not sure if any tire will not tend to track on parallel grooves since the tire is 'searching" for a line.

[Zooks]

Why does this freak people out so much? It's a total non-issue.

So the bike wiggles around a little on surface grooves. So flippin' what? It's meaningless. It doesn't feel anything at all like a loss of traction. So why all the whining?

It's just a very common complaint that I've never quite understood.

I think because it's a quite natural to be a little concerned when it feels like you're riding on marbles. Getting used to that feeling could be very dangerous on the day that you hit some real 'marbles' (a patch of sand for instance) on the same road.