Hydraulic steering damper

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acotrel

acotrel

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I have been wondering what sort of steering damper is normally fitted to road and racing Commandos ? Apparently the first Commandos had steering geometry which was originally specified by Peter Williams based upon his racing experience. A few inexperienced riders crashed when they rode over cat's eyes reflectors in the wet, - and the geometry was changed on later models by altering the fork yokes. If the first Commandos had more trail, they would probably have tipped into corners more easily and wobbled as the bike accelerated out of corners, unless they had a good steering damper. I've read about guys needing to reverse steer Commandos to get them to tip into corners. To me that would mean the trail has been reduced. Friction steering dampers work OK, but the damping does not increase as the oscillations become quicker.
My Seeley has 27 degree rake, 18 inch wheels and 105mm of trail. It tips into corners without the need to reverse steer, oversteers in corners, and does not wobble as I accelerate out of corners. However I use a Kawasaki adjustable hydraulic steering damper.

 
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swooshdave said:
Aren't steering dampeners just compensating for bad handling bikes?
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No they aren't, and they work together with good suspension and if you push your bikes to their limits then a steering damper is a must have.

Ashley
 
My Guzzi has one but only because they made the steering angle so steep. I can't imagine needing that for any of the Nortons.
 
swooshdave said:
Aren't steering dampeners just compensating for bad handling bikes?
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Nice theory, but when you are just using basically bicycle steering coming out of a bend doing three figure speeds whilst banked hard over, all it takes is a small bump/pothole to send your steering into a lock to lock tank slapper. It's happened to me a few times, and I've got away with it because I had restricted steering lock.
 
Bernhard said:
Nice theory, but when you are just using basically bicycle steering coming out of a bend doing three figure speeds whilst banked hard over, all it takes is a small bump/pothole to send your steering into a lock to lock tank slapper. It's happened to me a few times, and I've got away with it because I had restricted steering lock.
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Commando?
 
One tank slapper on the commando years ago, calmed it by gently applying the front brake. The head bearing were shot and the front wheel wasn't true. Corrected that and converted to tapered head bearings. Also installed a damper at the same time. Can't say if the damper is actually necessary with everything else properly set up, but I kept it for peace of mind anyway
 
Set your Commando up fot the the road, and, if you have done it properly, you will not have a problem. Steering dampers are for twitchy road, or, "race replicas". Good handling road bikes have little in common with rsce bikes.
 
Not sure I agree Ken.
I've never fitted one, but my '78 Suzuki 850 shaft used to "head wobble' from about 170-190kmh and back down) due to unevenly worn front tyre.
A new tyre fixed it - but I'm also fairly sure a hydraulic damper would have tamed it.
I don't think they can do any harm (other than to your wallet) as the don't affect normal steering, just prevent sudden/fast/large movements - which I think most would agree are undesirable to say the least.
 
I was recently reading about Joey Dunlop. Apparently he was almost illiterate, so most of his bike set-up was never recorded. He was secretive about his steering damper and used to wind it on as he rode in races. I have always had the minimum steering lock on my race bikes. When I had the Triton, I raced with only a friction damper and a few times had the lock to lock tank slapper. I survived a few by letting go of the bars and grabbing the tank, throwing the bike from side to side to steer it. When that happens, it is not nice. Once I grabbed the bars again, a bit too early and got launched. The last time it happened was due to locking the from brake to avoid a stupid idiot who had cut in front of me and braked hard. it was the only crash which I really believe could have killed me. After that I did not race very often. It still comes back to haunt me. These days I don't ride motorcycles which have drum brakes or those which don't have hydraulic steering dampers.
 
I think If I was going to race a normal Commando, I'd fit the fork yokes from the very first model, which was the crasher. - And use an hydraulic steering damper. As you increase the trail, strange and potentially beneficial things happen.
 
robs ss said:
Not sure I agree Ken.
I've never fitted one, but my '78 Suzuki 850 shaft used to "head wobble' from about 170-190kmh and back down) due to unevenly worn front tyre.
A new tyre fixed it - but I'm also fairly sure a hydraulic damper would have tamed it.
I don't think they can do any harm (other than to your wallet) as the don't affect normal steering, just prevent sudden/fast/large movements - which I think most would agree are undesirable to say the least.
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I see. So, steering dampers are to cover up inadequacies in bike condition?: Sorry, that's how it reads to me.
 
Not a fan of full on tank slapper , have had a hyd. damper fitted to the Norton for many years now , don’t really notice it even present anymore ...
 
Found it quite helpfull when 2 up and full luggage, to keep the handlebars steady whenever you take one hand off the handlebars.
Relatively not enough weight on the front wheel then, I guess.
About the lightest setting, on a NGK type ODM500 that is, proves already to be enough.
 
This is the Norton accessory hydraulic steering damper which many of you know about. I use it usually when pushing on bumpy, winding roads. It does help. I bought it for $20 at one on the San Jose British Motorcycle Shows put on by the local BSA club. Those days are gone.

Hydraulic steering damper
 
acotrel said:
If the first Commandos had more trail, they would probably have tipped into corners more easily and wobbled as the bike accelerated out of corners, unless they had a good steering damper.
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WRONG... You have never gotten the details of rake and trail correct in the few short years I've been here on this site. You clearly don't understand the physics. It's gotten to point of being annoying because you start all these "handling topics" in the forum and go on to try and sound knowledgable while getting the physics wrong every time...

The early commando's had LESS trail,.... and therefore had quicker handling, but because of less trail, they were inherently LESS stable... It's been explained to you numerous times...
 
slimslowslider said:
Found it quite helpfull when 2 up and full luggage, to keep the handlebars steady whenever you take one hand off the handlebars.
Relatively not enough weight on the front wheel then, I guess.
About the lightest setting, on a NGK type ODM500 that is, proves already to be enough.
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When the rear suspension is compressed, the steering head tilts back which increases the rake and trail and changes the way the bike steers so that it becomes more direct. As you brake the rake and trail decrease and the bike will tend to run wide. What a lot of guys do not realise - if you are in the middle of a corner going too fast and feel you are going to crash, it is often better to turn on more power than try to brake. As the front comes up the bike usually tightens it's line.
 
I don't know any way to get out of a very bad tank-slapper, other than to let go of the bars, grab the tank and wait for the bike to come out of it. When you do this, don't grab the bars when it al looks as though it has smoothed-out - just place your open hands on the bars. In a tank slapper, all the forces go through the handle bars. They can look OK, but might not be. If you grab them, you get flicked off the bike.
People who race without the steering damper are idiots, all they need to do is lock the front brake for an instant.
 
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