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steering damper

Started by david lee, January 05, 2018, 07:39:25 PM

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Hossamania

Quote from: david lee on January 11, 2018, 02:18:41 PM
Quote from: Harley_Cruiser Rocker Lockers on January 11, 2018, 10:24:03 AM
Trikes steer differently than bikes simply because they do not lean. The longer the trail the more stable the bike/trike is and the more the bike wants to keep going the direction that it is going. The shorter the trail the easier it is to turn and the less stable the bike is at speed.
On a bike you can overcome the long tail simply because you can lean the bike and force it to follow into the curve. On a trike you cant do this so on a trike that has a lot of trail it is very hard to make it turn, so trike builders will shorten the trail and add a steering damper on them to make them more stable. You can do the same thing with the steering head bearings by tightening them up and adding a dampening affect, as a mater of fact a lot of the old side car bikes had a big knob on the steering head to tighten/loosen up the head depending on the circumstances.
makes perfect sense

My friend's 1947 Indian has an adjustment knob on the steering head, probably because those bikes were set up to be used with or without a sidecar.
If the government gives you everything you want,
it can take everything you have.

david lee

Quote from: Hossamania on January 11, 2018, 07:31:52 PM
Quote from: david lee on January 11, 2018, 02:18:41 PM
Quote from: Harley_Cruiser Rocker Lockers on January 11, 2018, 10:24:03 AM
Trikes steer differently than bikes simply because they do not lean. The longer the trail the more stable the bike/trike is and the more the bike wants to keep going the direction that it is going. The shorter the trail the easier it is to turn and the less stable the bike is at speed.
On a bike you can overcome the long tail simply because you can lean the bike and force it to follow into the curve. On a trike you cant do this so on a trike that has a lot of trail it is very hard to make it turn, so trike builders will shorten the trail and add a steering damper on them to make them more stable. You can do the same thing with the steering head bearings by tightening them up and adding a dampening affect, as a mater of fact a lot of the old side car bikes had a big knob on the steering head to tighten/loosen up the head depending on the circumstances.
makes perfect sense
sidecars pull the bike sideways

My friend's 1947 Indian has an adjustment knob on the steering head, probably because those bikes were set up to be used with or without a sidecar.

JW113

Steering dampers were an option on the Indian, I've seen a few bikes with them. I agree, I think this is more of a sidecar option.

Not that I know first hand, but know a guy who builds and installs sidecars says if the rig is set up correct, it will not pull to the side. With a sidecar mounted, the bike is tilted outward (away from sidecar) to compensate so you have a neutral steering, no pull to either side. He is also a big advocate to mount car tires on all three wheels for a sidecar set up.

-JW
2004 FLHRS   1977 FLH Shovelhead  1992 FLSTC
1945 Indian Chief   1978 XL Bobber

Julio

Quote from: JW113 on January 12, 2018, 09:19:15 AM
Steering dampers were an option on the Indian, I've seen a few bikes with them. I agree, I think this is more of a sidecar option.

Not that I know first hand, but know a guy who builds and installs sidecars says if the rig is set up correct, it will not pull to the side. With a sidecar mounted, the bike is tilted outward (away from sidecar) to compensate so you have a neutral steering, no pull to either side. He is also a big advocate to mount car tires on all three wheels for a sidecar set up.

-JW

Even a well adjusted rig with the proper lean out, toe-in, wheel lead and level frame will need a dampner. I can run 90 mph on mine with no drift or head shake, but cross a set of railroad tracks at 20 mph, and the front end would go crazy. A VW dampner calmed everything down and is pretty standard equipment on all rigs.
As far as going dark side, tugging a tub is pretty hard on the rear tire. I never got more than 4k miles out of mine. I spun up an adapter for a 15x4 car wheel and now get a ton of miles out of the rear.


david lee

got the trike back from my hd mech who said the front was bent,one fork had different internals and was bottoming out on bumps and the damper was too short and at the wrong angle.he couldnt believe it rode it after his atempted test ride thanks all

76shuvlinoff

Critics are men who watch a battle from a high place, then come down and shoot the survivors.
 - Ernest Hemingway

Burnout

https://www.ebay.com/itm/41-mm-Panhead-adjustable-rake-tripple-tree-with-tube-adjusters-chrome/253595911746

This is what I used on my three wheeler.

Any head shake will dramatically reduce the time between welding up cracks in the frame.

After installing the trees shown above the frame has not needed any crack repair in 15 years.
They don't call me Ironhead Rick just because I'm "hard headed"

david lee

Quote from: Burnout on May 02, 2018, 08:58:24 AM
https://www.ebay.com/itm/41-mm-Panhead-adjustable-rake-tripple-tree-with-tube-adjusters-chrome/253595911746

This is what I used on my three wheeler.

Any head shake will dramatically reduce the time between welding up cracks in the frame.

After installing the trees shown above the frame has not needed any crack repair in 15 years.
never seen that those parts before.my mechanic said it will steer straight now with the front alighned thank you burnout

david lee

August 10, 2018, 04:16:12 AM #33 Last Edit: August 10, 2018, 04:22:51 AM by david lee
Quote from: harley_cruiser on January 11, 2018, 10:24:03 AM
Trikes steer differently than bikes simply because they do not lean. The longer the trail the more stable the bike/trike is and the more the bike wants to keep going the direction that it is going. The shorter the trail the easier it is to turn and the less stable the bike is at speed.
On a bike you can overcome the long tail simply because you can lean the bike and force it to follow into the curve. On a trike you cant do this so on a trike that has a lot of trail it is very hard to make it turn, so trike builders will shorten the trail and add a steering damper on them to make them more stable. You can do the same thing with the steering head bearings by tightening them up and adding a dampening affect, as a mater of fact a lot of the old side car bikes had a big knob on the steering head to tighten/loosen up the head depending on the circumstances.
i talked to a well known side car racer today and said a vw beetle steering damper is the answer . bike ones are not that strong in damping.i bought one today and now have to figure out how to fit it (mounting points)thanks

Burnout

Trikes work way different than a bike, what makes a bike stable, makes a trike unstable.

I am using a set of panhead side car trees on mine with standard rake and have no headshake or stability issues, no need for a damper.

Before, when it had a sportster front end on it, it shook so bad the frame had to be welded up once a month.

However Daves frame appears to be raked (generously).
His may not shake but just have the floppy wheel thing and obviously too much trail.

For this I would special order a Springer from Paughco and make some Sugar Bear Rockers rather than trying to make a hydraulic fork work.
This will put the steering forces at the contact patch instead of up high and off axis.
You need to accurately measure rake and calculate the trail before spec'ing the springer.
And it should not be a light weight unit.

Mounting anything but a stem type damper presents challenges and engineering compromises.
Ignoring that a damper is a bandaid for a symptom and doesn't "fix" anything.

They don't call me Ironhead Rick just because I'm "hard headed"

Julio

Quote from: david lee on August 10, 2018, 04:16:12 AM
i talked to a well known side car racer today and said a vw beetle steering damper is the answer . bike ones are not that strong in damping.i bought one today and now have to figure out how to fit it (mounting points)thanks

Headshake on a trike or hack is a weight distribution problem, not a rake problem. That's why Triglides and Freewheelers come from the factory with steering dampners. It's cheaper and easier to install a dampner than to reposition the motor and tranny forward to weigh the front end down and increasing the rake won't solve the headshake problem.
The VW dampner will solve your problem on the cheap. Certainly less than buying and installing a heavier front end. Your sidecar racing buddy should be able to help you on the install. For my hack, I used a 2 piece shaft collar and welded a tab for the front fork anchor. You'll have to figure out where to anchor in the rear to give it full movement.


david lee

im looking at buying this one as i already have the mounting points, one being a threaded hole on the tripple trees where you have welded a bracket. where as the vw one would have to have brackets made and welded at both ends on trike.to me the vw one is very stiff damping and would make steering to hard.thanks

HotRodShovel

david, who's dampener is that?  Where did you find it?  Some info please?
Sometimes life is like trying to share a sandwich with Rosie O'Donnell. 
John

david lee

its item number 113046484242 on ebay.my mate whos a mc mechanic and a wizard in metal fabrication said the vw one will work perfect and will design brackets to fit and checked the damper tension and said is what is needed.i like to look for alternatives.thank you

kd

Have you looked at the Harley dampThey were used on the late model sidecars. Both of my 98 anniversary RK and Ultra have them and I can actually run the Ultra on the 4 lane no hands with cruise on.
KD

HotRodShovel

Thanks David, I appreciate the info.  The new rebirth of my FrankenShovel will be off the lift soon and I'm anticipating the need for one.  I could be wrong and the road test will tell, but if I do Want to have my ducks in a row and get what I need.
These VW dampeners are new to me. 
thanks
Sometimes life is like trying to share a sandwich with Rosie O'Donnell. 
John

david lee

Quote from: david lee on August 11, 2018, 11:41:47 PM
im looking at buying this one as i already have the mounting points, one being a threaded hole on the tripple trees where you have welded a bracket. where as the vw one would have to have brackets made and welded at both ends on trike.to me the vw one is very stiff damping and would make steering to hard.thanks
my mate is coming down today to make brackets for the vw damper. the conventional one in the photo 330mm long wont fit due to the rake lenght and restricts turning circle. a 400mm might work but still might be to short.i will update on the vw fit.i just hope its not a ugly look.thanks

HotRodShovel

sometimes ugly is good.  interested to know how it all comes together. keep us filled in
Sometimes life is like trying to share a sandwich with Rosie O'Donnell. 
John