General Handling Question - Ice Skating Part II

[Sabre]

I read the recent "hey my ST1100 feels like it's on ice skates" thread and wanted to pick the brains of the experienced folks here. My 1300 does the same thing.

My new-to-me '04 has only 17K easy miles on her. The PO had flat-spotted the OEM tires in a dramatic fashion and she handled terribly. I spooned on a new set of Conti Road Attacks, highly recommended by several folks hereabouts. They're properly sized, balanced, and inflated (42 psi), and now have about 400 miles on them. They're well scrubbed in, and actually handled very nicely from the get-go. Except on the freeway.

The bike has no headshake at all, none of the "ST weave" that I've read about, but on the interstate it reacts very dramatically to any wind at all and has that ice skating feeling even on windless days. The turbulent air off semi trucks really blows her around and the frequent windy days that we've been having really make her squirrelly. I've been riding for 35 years and know all about having my bike pushed around by air, but I've never experienced such a "hog on ice" feeling. I'm used to having bikes pushed sideways in their lane and/or tilted by gusts, but never have felt such an odd movement.

Observations:
1. The forks and rear shock seem perfectly fine.
2. The steering head and swingarm bearings are fine.
3. The behavior is exactly the same whether riding solo or two-up, packed bags or empty.
4. It feels worse with the stock screen in the raised position.
5. The bike has the Hondaline Pan European top box mounted (no spoiler, no lights).
6. It happens on all sorts of pavement (concrete, asphalt, grooved or not).

The thing handles fine on county roads; this is only taking place at 60 mph and above on the freeway. It feels like the other poster described..."ice skating" really captures the feeling of each wheel having its own idea about where to go. It's like there's a hinge in the middle of the bike. The bike feels like it's rotating to the right and left about a longitudinal axis between the headlights and tail light. Very disconcerting.

Is this the back pressure thing that people talk about with the screen up? I've seen people putting various vents into their screens (cutting holes, putting in a Goldwing vent, etc). Is this done to address this issue? I read the advice to try removing the top box, and fully understand that the three pieces of OEM luggage back there are going to add a lot more sail area than the bike would have without them, but I've never experienced this feeling on any other bike with hard bags and top trunk. Granted, this bike has the largest coverage fairing of any bike I've owned.

Is this something you guys just get used to? Is this why people constantly seek aftermarket windscreens? Is this why Honda USA never imported this top trunk? Is this like a secret handshake among ST owners?

New guy wants to know. Gracias in advance.

 

[HillnTx]

I don't have an answer but my theory is the full fairing catches the wind and causes the bike to blow all over the place. I don't like riding mine in heavy wind conditions. I never had a noticeable issue on my naked bikes.

 

[Chance]

What you're describing closely matches the 'high speed weave' that seems to only affect certain bikes. Its cause has never really been found, there are a number of threads that address it. My '04 doesn't have it.. I'm 5'9 1/2" 200lbs., I ride with a topbox..I'm riding on PR2's and while I experience buffeting when passing trucks, have never had the 'on ice' feeling. Hopefully some other people that have, will chime in with ideas. Just be safe and keep us posted on how you solve this issue! <Sorry Im not more help.> :

 

[Sabre]

After reading more about the infamous weave, I note that most bikes are immune but some have it. This tells me that it might be something like wheel track being out. Is the rear wheel alignment adjustable like on a chain-drive bike? If the two tires are tracking out of parallel it would behave like this.

 

[dduelin]

If it is the "happy feet" feeling in turbulent air behind truck traffic - they all do it. Lighten up on the grips and carry on. Nothing is bent, broken, or damaged.

It's cliche...but you get used to it. The bike really isn't going anywhere, it won't get blown off the road or into another lane, or even off course. These are minute movements that feel larger than they are. It's disconcerting perhaps but in no way dangerous.

 

[wjbertrand]

Try cranking up your rear preload a bit. They come from Honda set very low. This should improve the angle of attack by raising the rear end and reduce lift, or at least the sensation of it, at speed. Make sure you have adequate rebound dialed in at the rear as well. Unless the bike has been in an accident, I doubt you have an alignment problem. I also recommend upgraded springs for the fork such as those available from Race Tech or Sonic.

 

[bkra13]

More rear preload would probably make it worse - it quickens the steering. My '03 with full rear preload "hunts" for a line on a freeway with out any wind at all - more stable at half setting. (no, haven't determined appropriate sag yet, just notes on how it's handling so far. rear remote reservoir was refilled so I have full range of preload). But yes, this bike is far more susceptible to wind - my zrx doesn't have nearly the wind sensitivity.

Just so we know - (you mention things 'seem' fine):

You mention swing arm bearing - is the swing arm pivot bolt tight?
What setting do you have your rebound damping at?
What setting do you have your preload at? have you checked the fluid level of the preload reservoir?

 

[ChipSTer]

Never had a problem on mine... I keep the wind screen all the way down... And keep the preload all the way up (but I haven't been in a windy situation since I lost 50 lbs)... I believe that is the key. YMMV

 

[wjbertrand]

More rear preload would probably make it worse - it quickens the steering

Understand the theory, but this has not been my real-world practical experience with the ST1300. I believe others have also solved or reduced weaving issues by increasing rear pre-load. I think too much sag at the rear takes too much weigh off the front wheel and lets more air pressure get under the bike, exacerbating the light front end issue. Ever drive a car or light pick up truck with too much weight in the rear? It's a similar sensation.

 

[SupraSabre]

If you have the windscreen up when passing tractor-trailer rigs or in strong winds, you'll get blown all over. Drop the screen down anytime you are in those conditions and see if that helps.

 

[bkra13]

Understand the theory, but this has not been my real-world practical experience with the ST1300. I believe others have also solved or reduced weaving issues by increasing rear pre-load. I think too much sag at the rear takes too much weigh off the front wheel and lets more air pressure get under the bike, exacerbating the light front end issue. Ever drive a car or light pick up truck with too much weight in the rear? It's a similar sensation.

Yup, understand that too. Hmm, going to have to play with this a bit.

 

[STDaveNW]

If it is the "happy feet" feeling in turbulent air behind truck traffic - they all do it. Lighten up on the grips and carry on. Nothing is bent, broken, or damaged.

It's cliche...but you get used to it. The bike really isn't going anywhere, it won't get blown off the road or into another lane, or even off course. These are minute movements that feel larger than they are. It's disconcerting perhaps but in no way dangerous.

+1 yup same here

 

[Sabre]

Understand the theory, but this has not been my real-world practical experience with the ST1300. I believe others have also solved or reduced weaving issues by increasing rear pre-load. I think too much sag at the rear takes too much weigh off the front wheel and lets more air pressure get under the bike, exacerbating the light front end issue. Ever drive a car or light pick up truck with too much weight in the rear? It's a similar sensation.

The sag in the rear has nothing to do with weight distribution...you can have no rear suspension at all and the front wheel will still carry exactly 50% of the static weight. Of course, the increased angle of attack of the bike will perhaps allow more aerodynamic lift at the front. However, I'm not convinced that a light front end is what I'm feeling. It feels like the front and rear wheels both want to wander...easily felt through the saddle and not felt at all through the grips.

If you have the windscreen up when passing tractor-trailer rigs or in strong winds, you'll get blown all over. Drop the screen down anytime you are in those conditions and see if that helps.

Hello, cousin!

Of course, and I've experienced this pushing on all of my bikes. The thing that's different here is that, unlike my experience of having the bike shoved from side to side with gusts or turbulence, or even pushed over sideways a bit from a very strong crosswind, this feels much more like the tires are sliding back and forth from side to side. The ice skating metaphor is spot-on...unlike all my previous experience, this feels like the two tires are acting independently of one another, each with a mind of its own.

I understand the statement that it's only a sensation, that it feels much more extreme than it really is. But it's unique in my experience of many different bikes, doesn't fit the expected behavior (in my experience) of a motorcycle to windy conditions, occurs even in still air, and is very disconcerting. Again, the fact that some report it and most don't makes me wonder about Honda's quality control in getting that rear wheel in alignment. Next step will be to check that alignment, then play with various configurations of screen position, trunk/no trunk, and suspension adjustments.

I very much appreciate the responses!

 

[dduelin]

Don't confuse this nervous feeling in freeway air with the high speed weave, they are two separate behaviors and if you experience the triple digit weave with your bike you will know this.

 

[Nevada]

There's another new thread that may shed some light on this.

 

[wjbertrand]

Of course you are talking about a static situation. Motorcycles don't wiggle when sitting still. Changing the preload can most certainly affect weight distribution and transfer when the bike is being ridden.

The sag in the rear has nothing to do with weight distribution...you can have no rear suspension at all and the front wheel will still carry exactly 50% of the static weight. Of course, the increased angle of attack of the bike will perhaps allow more aerodynamic lift at the front. However, I'm not convinced that a light front end is what I'm feeling. It feels like the front and rear wheels both want to wander...easily felt through the saddle and not felt at all through the grips.


Hello, cousin!

Of course, and I've experienced this pushing on all of my bikes. The thing that's different here is that, unlike my experience of having the bike shoved from side to side with gusts or turbulence, or even pushed over sideways a bit from a very strong crosswind, this feels much more like the tires are sliding back and forth from side to side. The ice skating metaphor is spot-on...unlike all my previous experience, this feels like the two tires are acting independently of one another, each with a mind of its own.

I understand the statement that it's only a sensation, that it feels much more extreme than it really is. But it's unique in my experience of many different bikes, doesn't fit the expected behavior (in my experience) of a motorcycle to windy conditions, occurs even in still air, and is very disconcerting. Again, the fact that some report it and most don't makes me wonder about Honda's quality control in getting that rear wheel in alignment. Next step will be to check that alignment, then play with various configurations of screen position, trunk/no trunk, and suspension adjustments.

I very much appreciate the responses!

 

[kieth]

1. Get the suspension set up for your weight and riding conditions.

A. change out the front fork oil and get the correct springs in it for your weight

B. Install a front fork Brace

C. after changing the front end and getting the preload and sag set for how yu ride, you will notice a need to change the rear shock because the rear is so bad. JMO

I spend money on suspension before anything else. having a bike set up properly is a art and science combined, we are fortunate to have experienced professionals here in Tulsa, Ok at K& N Yamaha they know how to set a bike up properly, at some events that they have they only charge $30.00 to adjust your suspension, it can make a world of difference. (no matter the brand )

 

[BakerBoy]

If it is the "happy feet" feeling in turbulent air behind truck traffic - they all do it. Lighten up on the grips and carry on. Nothing is bent, broken, or damaged.

It's cliche...but you get used to it. The bike really isn't going anywhere, it won't get blown off the road or into another lane, or even off course. These are minute movements that feel larger than they are. It's disconcerting perhaps but in no way dangerous.

+1 yup same here

for mine.

This jiggly feeling isn't affected by preload--it is the same whether set to max or min in my experience (preload has no appreciable effect on the front-rear weight distribution).

 

[Throttlejockey]

If it is the "happy feet" feeling in turbulent air behind truck traffic - they all do it. Lighten up on the grips and carry on. Nothing is bent, broken, or damaged.

It's cliche...but you get used to it. The bike really isn't going anywhere, it won't get blown off the road or into another lane, or even off course. These are minute movements that feel larger than they are. It's disconcerting perhaps but in no way dangerous.

Not true. It can happen.

https://www.st-owners.com/forums/showthread.php?103908-ST-s-are-dirt-worthy-at-speed...&highlight=

 

[jnsgardner]

Beg, borrow, or steal a fork brace. Four simple bolts, ride, and you can tell immediately if it helps. I also got a belly pan cover from CalSci long ago. It claimed to reduce reaction from turbulence. Does it work? It's been on so long now, I can't remember what it was like without it. The fellow at CalSci might be able to send you a copy of his old template. It's made out of black ABS (?) plastic 1/8 or 3/32 thick. It came with a scoop for cooling, but I swear mine collects more stones and leaves than air. The swirl pattern they put on the surface of some freeways might give you the effect you describe. God forbid you should ever drive over a bridge with open grating to let the snow fall through.
So try a fork brace. MCL and Superbrace make them for the ST, but borrow one first as they're over $100...oh, and don't forget all the other suspension fixes already suggested.

John