Wobble and Weave

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IMO, If it was my bike "wobbling" at 85mph i would be getting the front wheel balanced and or find out if you can drive through it.......... As for the weaving, well thankfully my interstate tank can be filled to the brim and then it wont weave......... hahaha.. i dont think so!!!.. I would be looking for "loose" wheel bearings , sloppy swing arm, low tyre pressure and the basic need for "wheel alignment"..
Interesting all the same and to get another opinion....
 
I always try to find what conditions make any cycle onset wobble and weave and they all can be made too but ain't yet been able on one isolastic tri-linked Interstate tanker. Much as might offend we should be studying the Harley handling and solutions as they are the closest things to how Commando handle or don't. I had long conversation with Ken Canaga last pm and he said he raced his isolastic's and never experienced weave wobble but did cause a crash by decreasing rake experiment. The late Kenny Augustine of World's Straightest Commando fame did not ride that one but bragged how his pilots eat up the field when he shorted the wheel base by slicing cradle to move gear box closer. I found I could induce weavie wobbles by slapping the bars hands off on moderns to regular Commmando's but one. I got into a confrontation with Kieth Code on what really steers a cycle, Kieth teaching-believes its the front tire while I found out its the rear the rules the roost, so last flings on my Peel were 110 mph in winter with huge wind screen jerking with body slams to lean hands off on Mt. hwy's while watching the forks automatically straight steer no problemo w/o a steering damper. Many factors combine to upset cycles see if ya can relate to this demo. If you ain't tried hobot low air zig zag practice staying in one lane then ya might not know what ya missing out on, or can be badly surprised by a slow leak.

[video]https://www.youtube.com/watch?v=Gmw6QppXnEY[/video]
 
I have never had the experience of wobble or weave on my current 850 Commando (or my original 750 Commando back in the day), either configured as a roadster or as a fastback at any speed that the bike is capable of or under any riding conditions (twisties, straight line acceleration, whatever) Seems to me that if it occurs, something is out of adjustment or damaged/worn excessively.
 
Worn out parts goes without saying.

A few things that seem to be common with all motorcycles in the Wobble and Weave scenario:

1). Wrong or worn tires or improper inflation. Tires and wheels not balanced properly.

2). Suspension worn or not adjusted properly.

3). Steering head loose or not adjusted properly.

4). Improper riding technique. This one is rarely talked about but hard throttle shifts can cause the bars to be pulled during shifting creating a dangerous condition (usually a tank slapper).

5). Improper weight distribution. This one seems to come up in most of these videos. It is the most common reason for Wobble and Weave and it should include options and loading of gear on a motorcycle.
 
How does a steering damper effect normal steering and handling?

Is it worth putting one on my bike?

If so, what's the best one?
 
I have owned four Commandos purchased as new in the early 70s

every one of them was quite capable of scaring the hell out me by going into the infamous Commando Weave

this occurs almost always when backing off the throttle from higher speeds, say over 70mph, both in and coming out of sweepers while banked over, and yes I know that the physics are far more stable if the throttle is kept constant but being young and fairly new to motorcycling over 40 years ago I did tend to carry more speed and needed to scrub some off in sweepers

the front end loads and the rear end unloads weight when throttle backed off, this makes the rear much more susceptible to a rubber mounted swing arm's side to side movements, hence the Weave

you can quite easily go into a handlebar swinging and fishtailing horror movie at this point and my experiences occurred with new Commandos, so in theory the rear ISO was set properly from the factory

I have added a steering damper set at medium clicks to my present 850 just as insurance against a tank slapper, don't know if it is really necessary or not as I make sure I don't get into Commando Weaves anymore
through setting the rear ISO around 4 thou instead of the recommended 10 along with carrying less speed into higher speed sweepers than in my exuberant youth
 
IF you have a Commando that never upsets you then you will not like a steering damper as makes a bit of annoying extra effort to steer while just toddling along. If there's some upsetting sense of the forks fighting ya then a damper will extend the speed/loads before it goes bonkers anyway though rather harsher meaner situation by that time to recover. So basically if ya ain't gotten scared by something having fun then a damper is just extra cost mass complexity decoration.

Some competition events, drag strips, air ports and hill climbs require them though so Peel's Scott damper bar clamp mount arrived today. Slip the pin in to engage and pull the pin to disengage. Many ways to skin this dampered cat.

https://www.google.com/#q=scott+steering+damper
https://www.google.com/#q=best+steering+damper
 
yes, there is a reason for fitting a steering damper

and that is because IF you do happen to go into the start of a tank slapper for whatever reason, you would be more likely to regain control when the handle bar swinging is a great deal more confined
 
Interesting speculations about steering damper reasons and behavior that do not agree with my experience so here's some others feedback on this touchy subject to ponder further. Why not just fit one and take off if you don't like it or leave it on if ya do, then get back to us. There are electronic ones out now that attempt to over come the innate annoying limitations of the non electric adjustable kind.

https://www.google.com/#q=tank+salp+wit ... ing+damper
 
1up3down said:
I have owned four Commandos purchased as new in the early 70s

every one of them was quite capable of scaring the hell out me by going into the infamous Commando Weave

this occurs almost always when backing off the throttle from higher speeds, say over 70mph, both in and coming out of sweepers while banked over, and yes I know that the physics are far more stable if the throttle is kept constant but being young and fairly new to motorcycling over 40 years ago I did tend to carry more speed and needed to scrub some off in sweepers

the front end loads and the rear end unloads weight when throttle backed off, this makes the rear much more susceptible to a rubber mounted swing arm's side to side movements, hence the Weave

you can quite easily go into a handlebar swinging and fishtailing horror movie at this point and my experiences occurred with new Commandos, so in theory the rear ISO was set properly from the factory

I have added a steering damper set at medium clicks to my present 850 just as insurance against a tank slapper, don't know if it is really necessary or not as I make sure I don't get into Commando Weaves anymore
through setting the rear ISO around 4 thou instead of the recommended 10 along with carrying less speed into higher speed sweepers than in my exuberant youth
Click to expand...


Forget the rest, buy the best.
If you don't own a Mk III, you can expect all sorts of
hairy handling shit. The Mk III is the culmination of
many years of learning. Everything previous to it was
nothing but a prototype!!

And I've still got my finger on the big red button!!
 
drones76 said:
Diablouph said:
I found this interesting. Wobble and weave starts about half way through.


https://www.youtube.com/watch?v=fvsDIq3WwVA
Click to expand...

Great video.

At the end, he says, "Use your loaf". What does that mean?
Click to expand...

Must be some peculiar pommy terminology.
I seem to recall my late 72 Combat was capable of a wobble
when riding hands off. Which one does not often do unless
testing the steering. But it never ever weaved, not even at
110mph. At that speed the engine blew up! 7000rpm was
107mph with a 19 tooth countershaft sprocket.

My Mk III shows not the slightest inclination to do either. The
only comment I would make is that it's very light and sensitive
steering feels almost too light at high speed. I compare this to
a Kawasaki Verseys I also happen to own (can't seem to even give
the bastard away). The Verseys is very stable at high speed, but
it doesn't want to go around corners like a Norton. You find yourself
climbing off the seat, or pulling the opposite handlebar, or both to
entice it into a lean. I would contribute those big fat modern bike
tyres has having something to do with this.

As for the guy in the video, he keeps suggesting everyone should
just lie down. At his age, that's probably all he feels like doing!
 
I don't find that big balloon tires affect moderns handing like you describe, ei: having to work the Kawi to lean. I find the big balloon tires merely make steering more sluggish but don't affect much whether a cycle innately fights ya to fling it down *in time* or fights ya to pick back up *in time*. My 650 Vtwin pitches over easy and stays down but tends to tank slap to pick up fast, while the 900 inline 4 would fight to fling down fast then took effort to keep it down low fighting tank slap with mean frame jiggles. Vtwin tended to low side ruin turn while the inline 4 tended to ruin turns by hi sides. The tendency to fight pilot to lean over or lean back up seems more to due with the bikes CoG front to back and up and down. Big fat very soft tires are the cat's meow for going straight-ish or freeway-ish turns but suck big time to me on they very edges compared to our skinny tires. My cycle life transformed once I found out that skinny tires stuck better on extreme leans under power, especially when on a Commando that didn't resist fling downs of flicks back up *in Time*.
 
I think we'd lose at least half the forum if everybody took their bikes to 90mph, shut off suddenly and sat up bolt upright. Mine had this instability problem since new. Went thru everything many times over 35 years but the only thing that cured it was a DT head steady.
 
7000rpm was
107mph with a 19 tooth countershaft sprocket.
Click to expand...

yep, that was about maximum speed for a Combat

the 850 managed a little more top end with the larger countershaft sprocket and 80 more cc/torque

also, that little hands off oscillation on your combat was another reason the factory kept the wheelbase the same but changed the rake/trail a bit on the 850s for a little more stability
 
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