1980 Suzuki GS1000G front wheel oscillation, wobble or shake

[Mickeymoe]

During my ride today I noticed that when I make a tight turn at very slow speeds the front wheel wobbles, oscillates, or "bounces" or something, I can feel it in the handlebars- it's not a comforting feeling. I can't come up with the best word at the moment, but I'm a bit concerned that it might decide to resonate at some higher speed and take the bike down sort of like the Dodge truck "Death Wobble" from a few years ago.

When I first looked at the bike in contemplation of buying it, I noticed that it had an ATK fork brace installed and didn't pay it any mind- now I'm wondering if that's why it was added by the PO. I removed it recently as I was updating the bike to the way I want it, now I have the "wobble". Before we conclude that the brace is what fixed the problem, I took it off because the front wheel felt heavy, like it was "falling over" on very slow tight turns.

My ex- GS850G, which was essentially the same bike, did not have this issue, which is likely why I scored a perfect score in the AMA advanced driving course about 20 years ago.

One more thing- since the day I got the bike I hear and feel a fairly loud "creak" occasionally when I stop hard with too much front brake, and when starting to move the wheel when the bike is parked- definitely coming from the front fork somewhere. That's primarily why I removed the ATK brace, I thought IT was flexing and creaking.

I bought my GS850G with 7k on it and sold it with 26k and it never had this issue so at 17k, my GS1000G (from the original owner) shouldn't be worn out yet.

Just for the record, the previous owner who bought it new had a side car on it for some time which he at least told me about when I went to look at it and subsequently bought it. Don't know if that factors in.

Any input would be appreciated.

Mark

 

[Tom R]

Could the noise be coming from th steering head bearings?

 

[Big T]

I'd start at the steering head bearings, then wheel bearings and alignment

How worn are your tires?

PS= if you want to get rid of that fork brace, let me know. But, it's not causing the problems

 

[Steve]

I will agree with bearings and alignment, but with sidecar use, I would also check the bushings in the fork.

Something is not aligned in the front end, which is what is creaking and groaning. Everything should be moving very quietly and smoothly.

When you removed the fork brace, did it lift right out, or did you have to pry it a bit? If you had to pry it a bit, something is binding.

.

 

[Guest]

How is the tire wear? Is it the same tire as when it had a side car on it. The reason I ask is I saw an episode on "How's it Made" the other day where they built side cars and after fitment they angle the third wheel inward a touch. I would think that might cause the front tire to wear a little differently. It may also effect the bearings, but the tire wear would be quicker.

 

[roeme]

What you are describing ("falling in", wobbly) are the symptoms I had when I neglected to mantain front tire pressure properly, combined with it being worn down.

Also, according to my knowledge, one usually puts a completely different style of tires on a bike with a sidecar; but surely those have been changed since?

 

[Mickeymoe]

I'd start at the steering head bearings, then wheel bearings and alignment

How worn are your tires?

PS= if you want to get rid of that fork brace, let me know. But, it's not causing the problems

Big T, The tires are brand new Metzelers, just replaced with about 200 miles on them.

 

[Mickeymoe]

I will agree with bearings and alignment, but with sidecar use, I would also check the bushings in the fork.

Something is not aligned in the front end, which is what is creaking and groaning. Everything should be moving very quietly and smoothly.

When you removed the fork brace, did it lift right out, or did you have to pry it a bit? If you had to pry it a bit, something is binding.


.

I agree something is not right with the fork, bearings, etc. But the ATK fork brace came off with no issues and I'll probably put it back on again....

 

[Mickeymoe]

How is the tire wear? Is it the same tire as when it had a side car on it. The reason I ask is I saw an episode on "How's it Made" the other day where they built side cars and after fitment they angle the third wheel inward a touch. I would think that might cause the front tire to wear a little differently. It may also effect the bearings, but the tire wear would be quicker.

Well the tires that were on it, replaced since new by the owner, were not worn at all actually. Just time for a change, so I put the same Metzelers on which now have ~200 miles on them.

 

[Mickeymoe]

What you are describing ("falling in", wobbly) are the symptoms I had when I neglected to mantain front tire pressure properly, combined with it being worn down.

Also, according to my knowledge, one usually puts a completely different style of tires on a bike with a sidecar; but surely those have been changed since?

roeme, Tire pressure is a good place to start. I haven't checked it since they were mounted a short while ago. The tires I bought a few months ago are new replacements for the same Metzeler Lasers that were on the bike when I bought it. (great, even tread but old). Nowhere in my research when buying a replacement set did I see any mention made of "sidecar" usage. I rode my GS850G for 20+ years and that bike became like part of my body and I could turn it lock to lock at any speed, almost standing still with no issues. That's why I picked this up so quickly. I think the GS1000G uses the exact frame as the GS850G too, so there's got to be some issue. I'm going to check the tire pressure immediately.

 

[Tom R]

The creaking noise you describe wouldn't be caused by tires worn, low or otherwise. That's why I'm thinking steering head bearings.

 

[Mickeymoe]

Yea, I agree Tom. It only makes the creak once in a while, like my back in the morning. BTW, I just checked the tire pressures and the front was down to 20psi so I bumped it back up to 25-26. Haven't tried it out yet but it was a good percentage low. I'm wondering if I just got so used to the Dunlop 481 Elite 2s? The tread is entirely different, although I wouldn't think that would have much effect and 3mph....

Mark

 

[bwringer]

Front tire pressure on that bike should be around 34-36psi.

Where were you getting 26psi?

 

[Mickeymoe]

Front tire pressure on that bike should be around 34-36psi.

Where were you getting 26psi?

OH MAMA! I don't know where my head was at when I thought 26 was the right number. Even the manual confirms your numbers! That's got to be the problem. I hope the rim isn't leaking. DAMN!

 

[limeex2]

Its more than likely the steering head bearings and new tires make it worse. Fork bushings could be worn, but usually will cause what people think are bad seals when in fact it is the bushings. To static check steering bearings, ride bike to 50-55mph, take your hands off the bars. Leave hands as close to grips as you can without touching. If the bike goes into a head shake while decelerating around 38-35 mph its the bearings. They are either bad or need adjustment. To check properly, put on center stand, lift front tire off ground. remove tire. Check wheel bearings should be smooth no rough spots, bearings very rarely go bad. With wheel off, move forks from side to side. With a bad steering head bearing, when the bars are straight,there will be a dimple in the race that will cause it to ratchet and you can feel it better with the wheel off. If they are dimpled, they will need replacement. Go with tapered bearing from All Balls. If adjustment is needed, adjust till it binds, back off nut about a turn and re-tighten until, when you push the bars, they slowly move/drop to the steering stops. If bike wanders back and forth after adjustment, its to tight. Properly adjusted steering head bearings with new tires is like getting a new bike! If this is not the cause, you have eliminated many possible causes that needed attention anyway.

 

[bwringer]

Agreed -- even very low tire pressure won't cause all the issues you report (but it will make them worse). You have multiple problems here, and the fine elements of the GSR Hive Mind above have given you several things to look at and correct.

With vintage machinery, it's never just one thing -- it takes time and experience to adapt your mindset away from "one problem at a time" thinking most useful on newer vehicles.

 

[Mickeymoe]

So it finally stopped raining and I took the bike out for a ride early Friday evening with 36psi instead of the 20psi that was in the tires. Unless I'm imagining it, the wobble seems to be gone. However, the front fork still makes a single "creak" when coming to a fast , hard stop using mostly front brake. The PO told me he had the front forks upgraded by the dealer (can't remember exactly what he had done) and the rear shocks are modern high-tech units. I must admit, the bike really smooths out bumps unlike my GS850G which had the chrome factory shocks. I think the aftermarket jobs are "progressive". I'm going to now put the ATK fork brack back on since the wobble is pretty much gone.

Mark

 

[limeex2]

Sorry I over diagnosed. It was a creaking noise. stand by the steering head adjustment though even though it would have nothing to do with a creaking noise. I need to add, when tightening the steering stem nut, loosen up the upper triple clamp bolts so the lower clamp may move freely.