General fork questions (on a gs650GL)

[Guest]

On my 81 gs650gL - Unlike the gs650g, the gL does not have pressurized front forks. The top retainer caps have no schrader valve. As a result, the springs are really long and relatively strong. Maybe I'm doing something wrong, but it seems like I have to compress the springs about .... 6-10 inches to insert the top caps after I've finished rebuilding them and adding oil.

Also, the manual simply says "fork oil: #15". Am I right to assume that means 15-weight and not something else?

I just ordered a bunch of parts because of how trashed the one leaky side seemed. The anti-friction metals were all scarred up, and someone forced a circlip where a springy round-wire retainer like on the top of the forks is supposed to go on the very bottom of the inner tube - the part that the bolt threads into. That has cut two deep gouges into the thing, but it doesn't seem to affect much. I would just replace it, but I don't see that clip on the parts diagram at all. So far, I have only disassembled the one side, but I can compare the two, since I ordered parts to rebuild both.

[Phred]

I bought fork oil at a local bike shop. Specifically for forks.

[TxGSrider]

Stick with "fork oil" as it should have stuff that keeps it from foaming and may have additives to keep the seals soft. Some of the fancy stuff by Fox supposedly has Teflon to help them move easier, but I doubt that we'd ever notice (or anyone else for that matter as I suspect its a marketing gimmick.)

[dorkburger]

Did you have the front wheel raised off the ground (or fully extended) when installing the springs? 6-10 inches seems like a lot, but I'm only familiar with my bike.....

[Charlie G]

Where you been so long? You're right about the 15w oil. I'm only familuar with 650 spring length. You should consider putting some new springs. Well worth the money on a 35+ year old machine!

[mmattockx]

As a result, the springs are really long and relatively strong. Maybe I'm doing something wrong, but it seems like I have to compress the springs about .... 6-10 inches to insert the top caps after I've finished rebuilding them and adding oil.

Also, the manual simply says "fork oil: #15". Am I right to assume that means 15-weight and not something else?

Progressive Suspension springs are often a good 6" too long and need to be significantly compressed to get the caps on. If you have a service manual for your bike it will have the length for the OEM springs, check them against that.

Do not use just any 15wt oil, use proper fork oil. You only need a liter (quart) and it is meant for that job specifically. With stock springs I would say go no heavier than 10wt fork oil.

Did you have the front wheel raised off the ground (or fully extended) when installing the springs?

Ah, fair question.


Mark

[WilliamGLX81]

Ah, great! Thanks for all the replies. Hey, @CharlieG!! I've been separated from my bike by a few hundred miles until last September. My friend brought it up to my new place. Unfortunately, while someone was "keeping an eye on it", it sat in the rain and someone stole my saddlebags
But it's getting some TLC and back on the road.

On the fork oil, I've been told that proper fork oil comes in 5w, 10w, or 15w. I mostly wanted to make sure it wasn't some special Suzuki part number.

The wheel is off the ground, but maybe I am just overestimating the length. My memory of my eyeball of the measurement *might* be wrong
These springs are two-part springs with a spacer between them. Here's a good diagram https://www.partzilla.com/catalog/su...t-fork-model-x . Maybe the two part spring is cheaper to manufacture than progressive single-coil springs and gives the same effect?

Cheers!

[tom203]

"...but it seems like I have to compress the springs about .... 6-10 inches to insert the top caps after I've finished rebuilding them and adding oil"

something wrong, maybe there is a debris in tube , so spring won't go all the way down. I recall only needing to compress spring about 2 inches ,hold it, and install the spring clip. I used a c-clamp vice grip to hold spring down while I fiddled.

[Gorminrider]

seems odd alright. Maybe check the damper assembly (per your diagram, nos.18-21) is seating right down to the bottom