Hi anyone know who made this shock and how it works. It has a valve on the little tank I assume is for air. Just go this 1987 k75s 

I'm pretty sure it's not a Works Performance shock.  Doesn't look like any of those shocks that have come through my garage. It might possibly be a Fox.

What is that large knob on the lower end of the reservoir? Is it a knurled aluminum knob?  Is there another knurled ring on the lower end of the shock just above the mounting eye?  If so, there is a chance you have a Fox Twin Clicker which is a pretty good unit that still has some rebuild parts available for it.

https://www.ridefox.com/service.php?m=moto

http://mahonkin.com/~milktree/motorcycle/fox-rebuild/Fox-twin-clicker-rebuild.pdf

http://evolutionsuspensionproducts.com/FTC.html

I've had several of those Fox Twin Clckers and rebuilt one of them myself.  With adjustable preload, and compression and rebound damping you can get them adjusted for a pretty good ride.  Of the 4 or 5 different shocks I've had on my Bricks the Fox is my favorite.

It seems to have some construction characteristics in common with the Progressive Adaptive shock absorber (pictured below) found on another old Brick recently.

I looked at fox and it is close but the progressive shown is it. If anyone has had experience with this shock I would like to know. It ain't shiny now but if it is decent and works is will be shiny again.

lucki wrote:I looked at fox and it is close but the progressive shown is it. If anyone has had experience with this shock I would like to know.

I haven't yet found any information about this relic.

In the absence of information, I recommend that you contact Progressive's technical department directly by using this email address. In the Subject line write, Information about Old Progressive adaptive shock absorber, then describe the age of your Brick and the situation. If you can paste the photos of the component with the Progressive sticker and the shock itself from this thread into the email, so much the better.

Latch
Any chance you can see a.model or serial number on this shock?

As per your suggestion to contact progressive, just did it now. Put a tire pressure gauge on the valve, no pressure on tank. Will put in about 10psi see if it holds.

lucki wrote:Latch
Any chance you can see a.model or serial number on this shock?

It'll need some steel wool scouring to reveal any clues, but to start off, there could be something in this area.

That's an odd place to mount the reservoir. Usually people mount them on the right rear frame rail. Like this:

10 psi is not enough to know if it holds pressure.  Those reservoirs are nitrogen charged with at least 150 to as much as 300psi.  The amount of gas charge is pretty small, so it's possible it all came out when you tried to check it. 

Tire gauges are not the way to check them.  They require a special test/charge setup and a high pressure(1000psi bottle) nitrogen source.  That charge is the only part of a rebuild that you should leave to a shop.

Confused now. So can it be used as is or scrap it. I'm not going to be scraping the pegs.

lucki wrote: So can it be used as is or scrap it. I'm not going to be scraping the pegs.

It's capacity to hold oil and gas pressure to function as intended needs to be determined by an experienced technician with suitable gauges and tools. Control of a motorcycle can be lost without scraping peg; just hitting ruts or potholes at speed can cause handling control problems if the rear shock isn't working correctly.

Are there any motorcycle shops in your area?  It sounds like you live in a rural area. 

If you can find a shop that sells sleds, ATV's and bikes, their shop will probably be able to do some rebuilding.  They can at least remove and install the spring and charge the reservoir.  Those are the only jobs you might not be able to do yourself.

You have nothing to lose with your present shock.  It sounds like you have removed the gas charge, so if you can remove the spring you can play a bit with the rest of the shock. 

The reservoir should have either a floating piston or a bladder that keeps the nitrogen from mixing with the oil.  One end of the reservoir will have a cap that is either threaded on or held in place by a ring in a groove. 

The shaft and piston in the body of the shock are held in place by a threaded cap on the end of the shock body.  There are several different ways these caps are turned to loosen them.  A good close up photo with the spring removed will help identify what tool you need. 

Internal parts usually include a shaft seal and a handful of o-rings to seal the pistons in the body and the reservoir.  If you find a bladder in the reservoir and it has a hole in it, unless Progressive can replace it, that will be the end of the line.  Otherwise, an evening of puttering and a few bucks in parts will get you back on the road.