Need to replace "oil locks"? (out of production part) when rebuilding forks?

[Guest]

I have an 81 GS1100E with stock/factory front forks, and I'm gathering parts and supplies to replace springs, flush/fill the oil, and replace as many seals, o-rings etc as I can while I have them apart. I've never tackled a front fork rebuild before, but I'm very mechanically able and between a factory service manual, a Clymers manual, and all the resources of the interwebs I'm not too worried. However there are a few components that seem like they might be wear components, or ones that should be replaced if the forks are disassembled, but that are no longer in production (and a quick search shows not much availability on EBay etc).

Since I've never actually had a set of these apart before, kinda want to check my intuition against the pros, and see if maybe these parts don't need to be serviced (don't wear appreciably, and unless damaged can be re-used with no worries). Since I'm not 100% sure exactly what function they serve (or how they accomplish that function), don't have a good feel for if they need to be replaced or can be re-used. Specifically, I'm talking about the following parts that are listed in the parts fiche, but no longer available from Suzuki:

• "O RING: 51148-49200" (#13 in schematic below)
• "PIECE, OIL LOCK: 51195-49200" (#14 in schematic below)

Basically I'm wondering if I need to put in the effort to track down a source for the "oil locks", or identify the #13 o-ring dimensions and track down an equivalent? All the other "wear" parts (o-rings, slides/seals, etc etc) are still available for reasonable prices, it's just these two items I can't find a replacement for. Want to try and get all the parts I'd need in-hand before I start tearing these things apart. Thanks in advance for the help

[Rich82GS750TZ]

When I rebuilt my forks the oil lock was fine, I don’t think this is a wear item, unless you somehow manage to damage the threads in the bottom of it when you remove the hex bolt under the fork.

** edit** there are no threads in the bottom of the oil lock piece, the threads are in the bottom of the damper rod which lives inside the oil lock. Sorry for the confusion. Thanks bwringer for the correction.

I would probably try to find a replacement for the oring. Someone else may recommend a material (viton? Idk) for that. I don’t believe fork oil would harm a rubber or any other material but again, not sure.

[bwringer]

The threads are in the damper rod, not the "oil lock piece".

The "oil lock" widget is pretty much just a spacer. It's not a wear item in any way.

No idea where that o-ring goes, honestly. Haven't seen one before, or maybe I just didn't notice. If it goes into a groove inside the "oil lock" thingy, then you can measure and find an o-ring easily enough.

A normal Buna-N metric o-ring will be fine with fork oil. No need for Viton unless you're just feeling extra-fancy or something.

You can buy metric o-rings from McMaster-Carr, but you'll get a bag of 50 or 100 at least.

[Rich82GS750TZ]

The threads are in the damper rod, not the "oil lock piece".

You’re right Brian, of course. I misremembered it wrong. Sorry to confuse the issue.

[Guest]

Awesome guys, thanks for the info! That's exactly what I was hoping to hear, too (not keen to try and track down some obscure out of production part). The mystery o-ring I am not too worried about. The fact its not listed anymore makes me wonder if its even actually used, or if so is in a position where wearing is not really an issue. If it IS there, and DOES look like it need s to be replaced, I work with o-rings a lot at work. I can measure up the old one and the gland on the part (gland = technical name for o-ring groove/recess) and if theres not a workable size on the Wall Of O-Rings in the lab, I will call up my guy at Parker with some dimensions and I'm sure he'll be happy to send me a few test samples to "evaluate".

Thanks again for the help gentlemen!

[Guest]

Just a quick follow-up for anyone who was watching this thread, or those who may come across it in the future searching for the same info:

Regarding the O-ring in question, according to this resource from RaceTech, the o-ring size is 14x2.0 mm (https://racetech.com/page/title/DRod%206-2%20KYB%2037mm). This link is a guide to modifying this particular fork setup for their cartridge emulator valves. So the part about drilling out the holes only applies in the that situation (installing their valves) but the pictorial teardown/rebuild guide is a bit helpful for those working on these forks.