Air Shocks

[1olbull]

The Progressive fork springs are a HUGE improvement if you enjoy greasing the twisties!
I wonder if proper sag and preload can be achieved with air?

 

[mully95]

My question would be "WTF would one want air shocks on there motorcycle?" I guess riding around in my friends jacked up 70 Chevy Nova years ago broke me from using air shocks on anything.

 

[1olbull]

My question would be "WTF would one want air shocks on there motorcycle?" I guess riding around in my friends jacked up 70 Chevy Nova years ago broke me from using air shocks on anything.

You silver tongued devil, you!

 

[barbagris]

The Progressive fork springs are a HUGE improvement if you enjoy greasing the twisties!
I wonder if proper sag and preload can be achieved with air?

Naturally. If you understand what you're doing.
A well set up air spring will simply outshine a steel one. As long as the damping is correct. I ran my old Guzzi on air for years - all across Europe. I was actually rather peeved when the bags rotted out.
Air gives natural rising rate springing - but to get it right you have to understand - weight, movement, volume, pressure.
My personal preference is to run airshocks a bit harder than spec'd.
Comes from experience and willingness to sacrifice a little low speed comfort for high speed twisties - especially riding a small tank.

 

[1olbull]

Naturally. If you understand what you're doing.
A well set up air spring will simply outshine a steel one. As long as the damping is correct. I ran my old Guzzi on air for years - all across Europe. I was actually rather peeved when the bags rotted out.
Air gives natural rising rate springing - but to get it right you have to understand - weight, movement, volume, pressure.
My personal preference is to run airshocks a bit harder than spec'd.
Comes from experience and willingness to sacrifice a little low speed comfort for high speed twisties - especially riding a small tank.

Found this on a physics forum about air shocks.
Found it an interesting read.

Whoa up fellows...there is no such thing as AIR shocks...even the old style air shocks ( were popular in the muscle car era) were conventional oil filled shocks that had a rubber bladder that could be inflated to raise the ride height of the car. As the air bladder inflated, it limited the shock travel and ride quality. ALL automotive and motorcycle shocks use " shock oil" that is forced through orifices to dampen the rate of compression or rebound. Lets review. Shocks provide resistance by forcing hydraulic fluid (oil) through valves in the piston as it moves up and down. Because the oil cannot be compressed, only a certain amount of fluid can be forced through these valves, which creates resistance to the vehicle movement. "GAS" shocks are superior to regular hydraulic shocks because air in the shock is replaced by pressurized nitrogen gas. The gas in the shocks is contained in a bladder to prevent the mixture of the gas and the shock oil, which is different from shocks where the oil is stored in a separate chamber or stored in the oil chamber. This advancement in technology prevents bubbles from forming in the hydraulic fluid. These bubbles, called foaming, reduces the ability of shocks to provide resistance and prevent bounce. Gas shocks also quicken the response of a shock's movement thereby increasing comfort and control under all conditions. When you think gas..think Nitrogen because it has less moisture and better properties than normal " air". We run the Penske "gas" shocks on the race car that achieve their damping with fluid being forced through a series of spring steel washers. Changing the thickness of these washers produces different valvings. Racers themselves can change the valving at the track! It makes these Penske shocks both rebuildable and revalvable. Not only can the racers change the oil themselves, but they can change the valving stack to achieve a different value. To illustrate how easy it is, both the compression and rebound damping can be changed in less than 10 minutes with no special tools (except an inflation valve to pressurize the shock with nitrogen. We carry a bottle of nitrogen in the trailer for this purpose and to inflate the tires.) In the old days we had to carry a whole bunch of conventional shocks and swap them out as they were manufactured with different compression and rebound rates. At $ 100 a shock this adds up! Penske shocks cost $400 and up...each! Another feature that makes these shocks the hot setup is that since they are rebuildable by the user, they can also be repaired by the user. If you bend the shaft on a Penske shock, you can fix it for about $40. With sealed shocks, you would have to buy another new shock if you bend it and on round track YOU WILL bend quite a few. So why the switch to gas shocks? Racers over the years found shock consistency to be a problem in two separate areas. First, shocks would not stay consistent ..see above info on "foaming) and secondly, after extended usage (over 30 to 40 hours of race time), the oil inside the shocks tended to break down and thus lose its viscous properties. After finding this out, shock engineers started investigating different oils for use in the shocks. They also investigated oil change intervals to keep the shocks as consistent as possible. The end result points to changing the shock oil after 30 hours of use, which translates into about a third to a half of a short track racer's season. Now a set of shocks, with proper maintenance and rebuilds, will last a racer five years or more. One final note: unless you come up with some totally new "air suspension" we are stuck with a variant of the tried and true spring/shock design.

Reference https://www.physicsforums.com/threads/air-suspension.483221/

 

[TOMCAT]

I have a set of HD air shocks that came off a '10 Road King but it would take some modification of the mounting points to fit them.

So you don't think the Showa air shocks from the RK are worth the effort of fitting? Got a set from a CVO that I was considering fitting to my Rocket .. what are your thoughts on the actual shocks mate?

 

[sweettennbabe]

Hmmmm. All I got was blah,blah,blah. Hard is bad!!! WTF... Since when is hard bad?

 

[R3Tex]

Shocks are fine...I have a set on my Ultra Classic...which is why I was gonna fit them on my '09. May have to go back to them and see what it will take to modify to fit the rocket. I don't want the wide variation in ride height, but I do like the fact that I can change the stiffness according to load. The '09 is set up for long range cruising and with a full load of swag that would come in handy. Typically when I have the pig on a trip I put 40 or 45 psi in them under load and then when I get where I'm going I drop the pressure back to 30 psi or so...very handy

 

[R3Tex]

One other thing...the road king air shocks I have are 12.75" and standard rocket is 12"

 

[TOMCAT]

One other thing...the road king air shocks I have are 12.75" and standard rocket is 12"

The ones I have are 12 inches long .. thought with the extra height of Extra Max I'd pick up the half inch I'd be loosing over the Roadster shocks (which I thought were 12 1/2 inches) I'm running now. Having never ridden a CVO Harley Tourer I have no idea what sort of ride the Showa shocks offer.