which fork spring and shocks for my 550L?

[DimitriT]

I'm having trouble ordering the right springs for a fork upgrade on the '82 550L. I called up the progressive customer line and there's only a spring for the GS550 with part # 11-1115. She claimed this spring is 19.75" long (if that helps any).

I've never messed with the forks before, so any help appreciated. Should I just pull out the old spring and measure?
BTW, do I need to disassemble the forks in order to change springs and oil? Will I need new bushings and seals if the
old ones look like they are working?

For the shocks I am looking at the 412 13" with part # 412-4211C. I like the look of the 418 better but its way too much "cha-ching", and who really needs machined aluminum with 20 combinations of settings.

[kalessin]

I just fixed my own forks for the first time, and posted some comments in the Tips & Tricks forum. You don't have to disassemble the fork inner tube from the outer (lower) part if you're replacing springs or seals (I poked a sharp pointy metal pick into one seal because I couldn't get the fork apart, worked like a charm...). You will want to replace fork oil when you have them apart.

Do you have a repair manual for your bike? In it, there should be a chart that mentions the proper length of the fork springs when measured. I don't know about the 550-size bikes, but the GS100GL forks are completely different from the 1100G, GK and E models. You can also fool around with spacers if you like.

You can pull out the old spring and measure, the un-compressed length should match what it says in your repair guide.

The Progressive 412 shocks should work just fine; I put some on a GS650GL years ago and they were great.

[DimitriT]

Thanks for the response. I just checked out your post in the tips section. Looks good. I am getting my confidence up to doing this. I still have a couple of questions, though:

The Clymer's manual says the stock upper spring measures 20.79". So I guess I need to find one close to that length and use a spacer to adjust preload. Is that how it works?

It looks easy to replace the oil seal by picking/pulling it out like you describe. But do I still need to do this if I'm just replacing the spring and oil? I want to know ahead of time so I can order the seal. My current seals look pretty good with no leaks, although I'm think of replacing the dust covers as they are cracked. I guess I'm still not sure how much disassembly I will need to do.

[chef1366]

Pcv

The springs do not have to be the same length as your because you can use PCV pipe to set the proper dampening. The directions for the Progressive Springs will fill you in in how to do this and how to damper your particular bike. My progressive springs came with the PCV pipe also so it is a recomended procedure even though it sounds hokey. You don't have to even remove your forks from your bike to change the springs. Just take off the top fork cap, carefully, with the front tire jack up with no weight on the forks. You can drain the oil through a drain plug at the bottom of you forks and follow the progressive oil level because it will change with a different spring.