Wobble - What to look for?

The Swiss Guy

Joined
May 24, 2024
Messages
19
Age
55
Location
Geneva - Switzerland
Hi guys,
My tried-and-trusted 1993 ST1100 now has 66 000 kms on the clock (41 000 miles), Recently, I noticed the wobble when releasing the handlebar got much, much worse, especially when decelerating, around 80km/h (50 mph).
The handlebars always wobbled between 50 an 80 km/h, and I was told by an old Honda specialist that it was always the case with these bikes. But now... it's on another scale altogether.
Knowing that the front bearings have been changed fairly recently... what else should I check?
 
The Swiss Guy said:
Knowing that the front bearings have been changed fairly recently... what else should I check?
Click to expand...
by "front" bearings I assume you're referring to the wheel bearings, right? (not the steering stem bearings?) can you clarify.

If this started after the front wheel was removed and put back on, also check that the axle tightening process was done correctly by loosening it and re-tightening in the correct sequence.
 
dwalby said:
by "front" bearings I assume you're referring to the wheel bearings, right? (not the steering stem bearings?) can you clarify.

If this started after the front wheel was removed and put back on, also check that the axle tightening process was done correctly by loosening it and re-tightening in the correct sequence.
Click to expand...
Correct. Wheels bearings, changed when we last changed the front tyre.
 
Ah, also, last time this happened, the mechanic checked the bolts that hold the fork, and found them loose. That was a few thousand kms back, so I don't think thes could have come loose again. But I will check.
 
The Swiss Guy said:
Ah, also, last time this happened, the mechanic checked the bolts that hold the fork, and found them loose. That was a few thousand kms back, so I don't think thes could have come loose again. But I will check.
Click to expand...
Our responses generally presume things like nuts and bolts are properly tightened.

Heck, even loose engine-mounting hardware can lead to unusual handling.
 
The Swiss Guy said:
I was told by an old Honda specialist that it was always the case with these bikes.
Click to expand...
Ummm NOPE mine is rock solid at any speed
I would look at tapered head bearings as an upgrade/repair but concur with all suggestions to check wheel bearings, proper alignment, improper tire pressure first.
 
Slydynbye said:
Ummm NOPE mine is rock solid at any speed
I would look at tapered head bearings as an upgrade/repair but concur with all suggestions to check wheel bearings, proper alignment, improper tire pressure first.
Click to expand...
His story is that when they were put on the market here in Switzerland, back in the '90s, people kept complaining about the wobbling.
And the only answer they got from Honda was:
"You are not supposed to take your hands off the handlebar"
He says they tried quite a few things, could never fully get rid of the issue.
 
the part about your story that's not common is the fact that you claim it went from having a little wobble to a LOT of wobble in a very short time.

There are several things that can contribute to the wobble, but they generally change very gradually, not rapidly, so that's the weird part about your claim.

1) As the tire wears, the wobble will increase
2) the steering stem bearings can sometimes loosen over time, but this is more likely to happen when the bike is new and the bearings are seating in
3) the front axle tightening sequence can sometimes cause weird handling effects

The claim that "all these bikes do it" is only partially true. From the factory, the steering bearings tended to seat and get loose, resulting in the wobble. But, if the bearings were properly re-tightened, or tapered roller bearings installed in place of the stock bearings, then the wobble could be eliminated.

Its possible that your steering stem bearings just decided to go loose on you, but its more likely that your tire has worn and is amplifying the wobble effect. Some tires cause the wobble worse than others, and can cause it even when being fairly new. What tire are you running currently? It may be that you chose one of the tires that are known to be worse in this regard, and that may explain the sudden change.
 
dwalby said:
the part about your story that's not common is the fact that you claim it went from having a little wobble to a LOT of wobble in a very short time.

There are several things that can contribute to the wobble, but they generally change very gradually, not rapidly, so that's the weird part about your claim.

1) As the tire wears, the wobble will increase
2) the steering stem bearings can sometimes loosen over time, but this is more likely to happen when the bike is new and the bearings are seating in
3) the front axle tightening sequence can sometimes cause weird handling effects

The claim that "all these bikes do it" is only partially true. From the factory, the steering bearings tended to seat and get loose, resulting in the wobble. But, if the bearings were properly re-tightened, or tapered roller bearings installed in place of the stock bearings, then the wobble could be eliminated.

Its possible that your steering stem bearings just decided to go loose on you, but its more likely that your tire has worn and is amplifying the wobble effect. Some tires cause the wobble worse than others, and can cause it even when being fairly new. What tire are you running currently? It may be that you chose one of the tires that are known to be worse in this regard, and that may explain the sudden change.
Click to expand...
I just went for a quick ride and checked tyre pressure.
Both tyres were under-inflated by about .5 bar (7.25 psi)
Tried to reproduce the wobble. Got mild wobble all the time, and serious wobble only once. Seems to appear on deceleration on a rough surface.
Tyres are Bridgestone Battlax BT-46F. Worn, but with life to spare (legal limit here is 1.6mm grooves, I measured 2.5)
 
Swiss Guy, my ST1100W would shake its head on deceleration from about 50 mph. If your hands were on the bars it didn't happen. I was trained in normal riding to raise my visor when entering 30 mph areas, so typically this would be done just before at around 40 mph, when the hand was removed from the grip you could feel the wobble, but with the other hand on the bar it would be mild.
To test I removed both hands and within 2 or 3 seconds the wobble got a little wild. If the hands weren't put back on the bars pretty sharp I think it would probably have resulted in an off.
Everything was OK with the bike and it was tyre sensitive, but not that dependent on pressure. The later T range Bridgestones were a little better. I never liked the 46's, they wore too quickly and went out of shape even more quickly.
The tyres are almost shot anyway, so before the next riding season I would switch to the latest T Bridgestones and see how it feels then. Are we on 33's now? Make sure you go with Bridgestones recommendations for pressures not Hondas.
I had a similar experience with a CBF1000, that was rock steady on Bridgestones, I put Michies on and it would shake violently if you dared to remove a hand from the bars in the same situation.
In short, it's tyres. But exacerbated by riders weight, loading, tyre wear, pressures, etc.
How did the tyres end up 7.5 lb under pressure. I can leave my tyres all winter and they'll only lose a pound or two.
Upt.
 
Upt' North said:
Swiss Guy, my ST1100W would shake its head on deceleration from about 50 mph. If your hands were on the bars it didn't happen. I was trained in normal riding to raise my visor when entering 30 mph areas, so typically this would be done just before at around 40 mph, when the hand was removed from the grip you could feel the wobble, but with the other hand on the bar it would be mild.
To test I removed both hands and within 2 or 3 seconds the wobble got a little wild. If the hands weren't put back on the bars pretty sharp I think it would probably have resulted in an off.
Everything was OK with the bike and it was tyre sensitive, but not that dependent on pressure. The later T range Bridgestones were a little better. I never liked the 46's, they wore too quickly and went out of shape even more quickly.
The tyres are almost shot anyway, so before the next riding season I would switch to the latest T Bridgestones and see how it feels then. Are we on 33's now? Make sure you go with Bridgestones recommendations for pressures not Hondas.
I had a similar experience with a CBF1000, that was rock steady on Bridgestones, I put Michies on and it would shake violently if you dared to remove a hand from the bars in the same situation.
In short, it's tyres. But exacerbated by riders weight, loading, tyre wear, pressures, etc.
How did the tyres end up 7.5 lb under pressure. I can leave my tyres all winter and they'll only lose a pound or two.
Upt.
Click to expand...
Very useful, thanks.
Agreed, I will get that tyre changed ASAP.
I ride all year long, and my last tyre pressure check was in summer, so I guess it's just summer/winter difference.
 
The fact that this issue got worse after your bearings were replaced may be significant. The bearings have to be installed in the correct order, but even if that was wrong I doubt it would make that much difference. Although I dont know that for certain.

What is siginficant is that the wheel has been out. Take a look at my video for the St 1300 in the link below.

The 1100 is different, but the idea is the same.

Instead of two collars with flanges, the 1100 has a collar on the right (brake lever) side, and a speedo gear mechanism on the right.

The axle has a shoulder on it, and the idea is that this pulls the speedo gearbox across to the right hand side of the bike clamping together the gear box, the left bearing, the distance collar inside the hub, the right bearing and right hand collar. These are all pulled tight against the right hand fork leg when the axle bolt is tightened.

If the fork pinch bolts are tightened before the axle is properly torqued, this clamping cannot be achieved. If this happens the everything is apparently tight, but the wheel is able to slide side to side in the axle !

Watch the video how the bolt clamps everything together. The axle on the 1300 ends up flush at the left hand end. The 1100 does not - it has a hole for inserting a rod to hold the axle still while it is tightened. I seem to remember a score mark to indicate where the fork leg should align. Anyway watch - you'll get the idea and be a le to transfer that info to your 1100. Note that the fork bouncing is important before tightening the pinch bolts.

Article [13] - ST1300 - Maintenance - Front & Rear Wheel Install and Front Axle Animation | ST1300 Articles

Animated sequence to show the correct procedure when installing the front wheel into the forks of a Honda ST1300. The right hand side of the bike is the side with the brake lever. Left is the clutch lever side. This is the convention used in the Honda manuals. The video and the photo below...
www.st-owners.com www.st-owners.com

The 1100 has a speedo cable. Make sure that the routing if that is not interfering with the steering. Also that when the axle is istalled that the lug on the speedo gear housing is correctly located in relation to the lug on the inside of the fork leg - preventing the gear from trying to rotate around the axle as the wheel turns.

And since the wheel has been out by someone else, just check that for each pair of brake pads, one is fitted on either side if the brake disk. Yes I know, but I have seen photos.....
 
The Swiss Guy said:
His story is that when they were put on the market here in Switzerland, back in the '90s, people kept complaining about the wobbling.
Click to expand...
Huh?!
A long time ago we had this "discussion" on STeinar's famous mymc PanEuro email list...
It soon was found that, besides worn front tire, improper rear shock setting and/or worn rear tire (as well as improper payload distribution) were ID-ed as source in the majority of cases...
Followed by "wrong tire choice"... (some brands/types, like Dunflop, just don't work on an ST...)
Worn head bearings, fork bushings, loose bolts, misaligned assembly were actually a minority...

My '00 model on new G547/G548 tires: no dec wobble at all... once the G547 (front) is at the end of its lifetime: some slight dec wobble, but controllable...
(I recall having tested a new set of BT45 back in the day, the front showed a quite noticeable, annoying wobble, even while leaned/in corners... took them off after only a weekend, installed G547/548, the ST rolled perfect again...)
 
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