Well, I haven't had my GS very long yet but I'm already making a list of modifications I want to make to it 

Near the top of my list is to upgrade the shocks (front and rear). I think I'm gonna go with either an R6 or Katana 600 for the rear. Anyone have experience with either of these? Which is better? What is your preference?

Also, if anyone has recommendations for the front shocks feel free to speak up.

The R6 shock is a much nicer design than the Kat600 shock. The Kat750 shock is more comparable to the R6 shock.

The answer depends primarily on how much you weigh. The Kat shocks have a very stiff spring. If you weigh upwards of 250lbs, it'll be a good spring for you. If you're under that, the R6 shock is going to be much better.

Thanks for the info. So far everything I've seen seems to say the R6 is my best bet.

Do you know if installing the R6 shock will raise the bike at all? I saw some threads (mostly referring to the Kat750 I believe) that mentioned minor problems with the kickstand do to a change in height after swapping shocks.

I have progressive springs in the front and a kat shock in back.  It raises the overall ride height due to the bike not sagging like a marshmallow when you get on, but never had a problem with the kickstand.

I have no problem with the Kat shock and at the time I put the most miles on the bike I was less than 200 lbs with gear.  I think the most important factor isn't necessarily which shock you choose but the quality/condition of the shock you put in.  Make sure your front suspension is matched to the rear.

I also have progressive springs in the forks, and a kat 600 shock in the back.

I've yet ridden the bike with these upgrades.. gotta finish the engine...  I don't weigh much, so that worried me a bit. but I'm building a more "adventure" GS. trying to keep it stock.. but at this rate, having ground clearance issues with the stock manifold.. may have to re-route  it up the side, that would also require a heat shield... sometimes I question my intentions, and where exactly im going with this bike.. lol also keeping the stock forks instead of going with something with more fork travel.. we'll see how this ends up I suppose...

Not exact on the numbers but I remember reading the R6 spring is rated at about 9.0kg/mm and the kat is more like 10-11kg/mm. You be your own judge. I put an R6 on mine cause I weigh 130lb and I put a katana on my cousins cause he weighs 200lbs.

Neither should raise the bike significantly or at all. I didn't notice any difference on the bike height. I think you're thinking of the sv650 shock. That one requires some cutting/drilling to get the eyelet down at the same size as the gs500, otherwise it will lift the bike up a few inches.

The height I mentioned may be illusory but there's no doubt the feel of the suspension is significantly different, for the better.  I was 175 w/o gear and it was great but I'm sure the R6 shock is great as well.

well, I find myself loading up my bike with stuff from the store, or another person. almost all the time, so the extra stiffness works of out for my situation and needs.

Just gotta carry around that little stupid tool they give you for adjusting the rear-shock.. and a pipe to fit over the end of it, because turning those god darn things with your hands, and its little short handle is almost freakin impossible. 

Well, after reading some more comments I'm back and forth on the R6 or the kat600. I'm about 210 without gear, I think either shock would work pretty well. So more than likely its gonna end up being decided by which one I can get a better deal on.

So now I have to start thinking more about front springs. What exactly are progressives? What are your favorite options for front springs?

Thanks

Since it hasn't been mentioned, I'll offer the other option to progressives, which are straight rate springs.... there are two brands that folks use in their GS500s and they are either Racetech or Sonics springs.

The owner of Sonic Springs is a member on here as well - RichDesmond.  He has a calculator available on that site to determine which spring rate you need.  Depending on how you ride, you would need either .9 or .95  If you are not an overly aggressive rider, or don't ride with a lot of extra weight (gear or pillion), I think you would be most satisfied with .9 - but you can certainly contact Rich if you are unsure about it.

http://www.sonicsprings.com/catalog/index.php?cPath=31_65&osCsid=c16aac8429810a6543b50406bd5433f8

You might look into the literature out there regarding the debate between the two.  I can tell you that I did when deciding, and ended up purchasing Sonics... however, I encourage anyone to research and decide themselves.

- Bboy

The front spring rate depends heavily on your riding style. I'm about 175 geared up with an R6 rear on middle settings all around and .85 springs. I feel like my suspension is very well balanced for spirited riding, and it still does alright on long highway rides. Too stiff and you'll bounce around like a squatting civic. But I also ride primarily alone with small saddlebags. If you'll be riding with a passenger or lots of gear, you will probably be satisfied with .9 fronts and Kat rear.

I've got the kat600 shock and .85kg racetech springs installed.
Sadly haven't been able to ride it yet as I still have no brakes, because  my rotor is bent front by accident :-(

Thanks for all the advice. I think I am going to go with the R6 rear shock and 0.9 straight rate front springs.

Now that I know what I want I just have to set aside a little cash and then some time to order/install them.

That's great! I think you'll be very satisfied with that setup.  You'll be on the higher end of the R6 (which is perfectly fine!), but also well within its capable effectiveness, and it will give you loads of adjustment options to really tune it in for your riding.  The .9 springs should really work out great too.  Properly set your sag with preload in the forks, it'll be a completely different bike.  The suspension on the GS500 is probably the most lacking aspect of its build from the factory, and is well worth the investment to upgrade it.  Don't let me talk it up too much, it'll still be a GS500, but you won't be disappointed with the time or money spent!

- Bboy