The photo above:  left to right...
GS, 750 kat, 750 Kat (Both short clevise), Old GS700ES, Old GS700ES (identical to the katana shock with the exception of that cable puller), and Kat 600.
The RF and bandit 12 shocks have the preload on top and the adjustment dial in the clevise. The Old slingshot shock and the RF shocks have aluminum clevises. The B6 shock is just like the B12 shock with the exception of the rebound dial. None of these have remote reservoirs.

The most recommended replacement shock for the GS500 is an '89+ Katana 600 standard issue. The katana was a GSX 600 F. In most cases Katana is the katana 600 (not 750 or 1100) from 89-02. They made a 600 Kat in 88 also but that shock was not as good as the later one. It only had spring preload vs. the spring and rebound in the later ones.

The Bandit 6 was first made in 96 and its shock is junk. The Bandit 1200 was made in 98 and they are the GSF series. The B6's shock had only spring preload adjustment and is more heavy duty than the GS500 but putting in the money and effort of replacing the shock you might as well get the best you can.

A bandit 600 shock does have its place in the 500E's world though; its 3mm shorter than the GS's shock and is a bit more heavy duty than the GS's shock. That will make the rear end sit down ~1/2-1 inch with no load. That may just be the ticket for shorter riders. But if you are lighter than 150 or so lbs the stocker should be fine.  That little niche of people can use a B6's shock. Lower and better ride for the most part.

The RF600 shock has a very deep clevis so you dont need to grind anything.  The katana shock has the adjustment dial on top and its easier to fiddle with than the RF's. Also I believe its a bit softer than the RF (which may be too hard). The RF900 has a cable adjustment for rebound which is junk-just remove it and fiddle with it by hand for adjustment. RF900 has a dial on bottom for compression dampening adjustment.

The RF600 or 900, Kat 600 or 750, Bandit 12 and a slew of other shocks will fit the alloy linkage bikes with no grinding. The steel linkage GS's will need some shaving of the linkage if you want to run a short clevis shock (the RF shocks, B12 and the 750 Kat shocks are all short). The long clevis shocks bolt right in.

The GSXR shocks (long clevis, requires grinding of linkage) are great for a race bike on the street they are sometimes over kill. In addition to being sprung more than is necessary for this bike it raises the rear up by ~1"-2".  This causes it lean too much on it's sidestand or you can extend the sidestand by welding an additional 1" to the center, the centerstand doesn't hit the rubber stop on the pipe when up, the chain rubs the top of the swingarm and/or the centerstand, the shock can sometimes hit the body of the swingarm, etc. No end of little problems. The cool factor is there with the remote reservoir but you have a somewhat hard ride on the street and a bike that is a little too high for a street bike. For a street bike I'd stay with a Kat or RF type shock. Race bike a GSXR; and a 750 GSXR shock is better than a 1100. Those 1100's are pretty much junk

 

I have installed a '95 GSXR shock on my bike and can attest to the niggling problems associated with it. I have an additional 2" added to my sidestand, otherwise the bike looks like it will fall over with a stiff breeze. Also, the '95 is the year the GSXR shock got wider coil springs which slightly rub the front of the swingarm on my bike. However, this doesn't always occur due to manufacturing tolerances (or lack thereof). Rear of bike sits much taller although I've been told it's only an inch or two (with bike on centerstand the rear wheel still touches the ground). Rides great though-not as rough and inappropriate for the street as some would have you think, and I'm a small rider at 5'-6", 120 lbs.

If I had to recommend one for another rider (or do it myself all over again) I'd recommend the Kat600 shock for it's ease of install and for being trouble free. And John can attest to it's desirability on the street. If you're racing the GSXR shock is the way to go though.

With any change to the rear suspension you should check your chain tension. After I installed the GSXR shock I had to retighten my chain quite a bit.

Also, when you raise your rear end you'll have to deal with the sidestand being too short (bike will lean over precipitously). Doug, whom gave me his GSXR shock also gave me his extended sidestand. Here's how he did it.

After I put on my new suspension I was only able to go for rides where I never got off of my bike.  My center stand needed a 2x4 under it, and my sidestand leaned the bike so far over that it fell right over. I was looking for a kickstand that would work with the new height brought on by the GSXR suspension and I was unsuccessful.  When looking you need to have the spring tab, the kill switch tab and the mounting hole in the right spots relative to the bike.  I could not find anything that would work.  I resorted to lengthening the kickstand I already had. These are the steps I followed.

1. Measure how long you need to lengthen the kickstand. I had mine mounted and in the down position.  I leaned my bike over to the angle I wanted and measured the remaining distance to the ground.  It was about 2" on my bike.

2. Mark the kickstand with either paint or crayon the full length in one spot; this will be used to line up the two pieces later.

3. Take your saw of choice... mine was the sawzall. Cut the kickstand in half a little below the tab for the spring. (This will keep all your tabs in the right spot for the bike).