Steering damper

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Chuey
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Joined: Mon Aug 02, 2010 11:56 pm

Steering damper

Post by Chuey »

As some of you know, in February, I crashed my R90S due to a tank slapper of a speed wobble. If I had been using my steering damper, would it have likely prevented my tank slapper? Is it considered an effective device?

Chuey
Kurt in S.A.
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Re: Steering damper

Post by Kurt in S.A. »

In that situation, I would think that the damper might have slowed the steering response (back-n-forth), but I've never been in those type of situations...knock wood. The dampers are meant for full-on racing which have heavy braking loads as well as severe gyroscopic loads on the front end. They are also meant for riding on rutted roads to keep the wheel from jerking out of your hands.

But to use the damper as a bandaid for a poor suspension setup is not something that should be relied on. One should get the suspension in solid shape...in that case for normal operations, a damper is of no use.

Kurt in S.A.
Major Softie
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Re: Steering damper

Post by Major Softie »

As Kurt says, it's a band-aid, and not the "best" solution (of making sure there's no problem that will cause a tank slapper in the first place), but YES, they do keep tank slappers from happening, and that's exactly why they are on race bikes that have very quick steering geometry that is right on the edge of instability.
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Zombie Master
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Re: Steering damper

Post by Zombie Master »

My R100 has one. The only time I use it is when there are a lot of side winds. It does calm down thing in that condition.
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Rob
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Re: Steering damper

Post by Rob »

Speaking of tank-slappers, I once tried to install some RS bars on my /2 conversion rig...
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Rob V
Chuey
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Re: Steering damper

Post by Chuey »

Rob, I want to get it but I don't get it. Please 'splain.

Chuey
Rob
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Re: Steering damper

Post by Rob »

Chuey wrote:Rob, I want to get it but I don't get it. Please 'splain.

Chuey
One needs width (leverage) to control the front end. Especially when the front forks are set to "sidecar" mode (steep).

Flanders sells low bars especially for sidecaring. They are wide.

The RS bars are narrow.

After I had had my R65 for a while, I wanted to try something more extreme than the Euro bars, so I bought the set of RS bars. But my brake reservoir would not clear the dashboard.
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Duane Ausherman
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Re: Steering damper

Post by Duane Ausherman »

I speak from some experience, as I have dealt with this issue for a very long time.

The steering damper on the R90S and others of that era were pitiful examples of an attempt to provide boiler plate insurance to a known problem. One not fully addressed by the longer rear swing arm.

Those found on racers are quite different. Those are fixed and have no linkage to wear out. Very soon the type used on our BMWs started to wear and they would have a lot of play before the hydraulics came into play.

A savvy rider can easily discover if a bike is stable, or unstable. All of my employees could divide the level of stability into at least 4 groups, from mild to killer dangerous. Even my parts people had done the test riding to learn this skill.

Since dangerous wobbles can be predicted ahead of time, nobody should be getting injured. It isn't uncommon for someone to change one part on a bike and it becomes a serious wobbler.

I hesitated putting the information on my website and after getting requests for several years, I finally relented and starting about 10 years ago, I have included some, not all, but some of what we had learned.
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