RS forks. Switching parts?

flamin'trek

Likes Bikes and Dirt
I have a set of RS Reba dual air forks that I've tried to service and have failed twice, there is something wrong with the compression damping. I also have a set of RS Recon solo air that have scratched stanchions and are playing up and in need of a service. Both are 32mm legs and of similar vintage around 2008.

Might it be possible to do a bit of mix and match? Are the uppers, lowers, internals compatible enough to go ahead with a teardown and make a decent set out of one?

Gut says 'go ahead. what could possibly go wrong'. Other voices saying '2x paper weights' and 'Trying to find replacement 26" straight steerer forks won't be fun'
 

Plankosaurus

Spongeplank Dalepantski
What's wrong with the compression damping? These are a pretty simple design so there might be something you can do about it still.

And yes, a lot of the 32mm rockshox stuff is compatible, even between different models and eras sometimes. If you're a little bit mechanically switched on I'd say pull them both down and make a good set. If you can't fix the rebas that is, still reckon they'll be salvageable...

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Mr Crudley

Glock in your sock

Flow-Rider

Burner
Steel and alloy stanchions have a slightly different ID between themselves, so you'll need to stick to the same type. If the damper is a different length you'll need to adjust the oil level to suit.
 

Mr Crudley

Glock in your sock
Steel and alloy stanchions have a slightly different ID between themselves, so you'll need to stick to the same type. If the damper is a different length you'll need to adjust the oil level to suit.
True, steel - silver and gold = alloy from memory. apparently they didn't make too many changes to the CSU hence some chance at mix n' matching. YMMV, of course :)
 

The Duckmeister

Has a juicy midrange
True, steel - silver and gold = alloy from memory. apparently they didn't make too many changes to the CSU hence some chance at mix n' matching. YMMV, of course :)
Pretty sure at that vintage all Recons were "Gold" aluminium stanchions and the Silvers were the Tora range. Later evolutions changed the distinction and put coils in the Tora & air in the Recons, with both having "Silver" and "Gold" options.

Rebas of that vintage share dampers with the Recon, but get the leg up with dual-air spring. Pretty sure my '13-ish (whatever the last year of dual air spring was) Reba uses excatly the same Motion Control dasmper unit as the '08 Recon it replaced.

The dampers themselves are nothing funky, basically a plastic canister with a rotary valve in the bottom opened & closed by a shaft connected to the lever on top. Remote lockout cartridges have a spring on the shaft to open the valve when the lock is released, non-remotes are not spring-loaded. "Motion Control" cartridges are designed in such a way as for the whole thing to be slightly compressible, so that when the valve is closed to stop oil flow, you still have a small amount of compliance rather than a rigid lock.

Remote-lock MC shafts can get sticky over time, typically manifested by the valve not properly opening because the spring can't override the friction on the shaft. It can be confused with a sticky cable, because the symptom is the same. Sadly, despite being such a simple contraption, the damper cartridge is pretty well unserviceable. Fortunately, very easy to replace, and I believe modern Recons still use essentially the same damper, although the shaft spring for remote versions is reversed, so the default position is locked instead of open.
 
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flamin'trek

Likes Bikes and Dirt
Thanks all. Appears both sets have the same colour legs. Sounds like it is worth having a go at rebuilding the Reba’s back to full functioning.

The scratching on the recons is pretty bad, the whole bike they came on looked like a blind hammer mechanic cut his teeth on it. The Reba are in otherwise good condition, so probably worth resurrecting.
 

Plankosaurus

Spongeplank Dalepantski
What ducky said

I'll add that the compression damper units from that era had a habit of leaking from the lockout seal. Can't disassemble to fix either so hold onto the spare from the recons.

Also, if someone has installed a rubber seal instead of the foam ring under the dust seal it can stick and make it feel like the compression or rebound damper are playing up. Easy fix to just pull the out and replace with foam rings.

And also, there was a common issue with the lower damper shaft seal letting oil through into the lowers. Lockout won't work properly and eventually you'll fill the lower with oil and it'll be locked out till you empty it. The O rings cost a few cents each from an o ring supplier if you can get the size right (can't recall the sizes)

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The Duckmeister

Has a juicy midrange
And also, there was a common issue with the lower damper shaft seal letting oil through into the lowers. Lockout won't work properly and eventually you'll fill the lower with oil and it'll be locked out till you empty it.
If that happens, rebound damping will be non-existent too, because there's no oil going through that damper circuit.
 

Mr Crudley

Glock in your sock
Pretty sure at that vintage all Recons were "Gold" aluminium stanchions and the Silvers were the Tora range. Later evolutions changed the distinction and put coils in the Tora & air in the Recons, with both having "Silver" and "Gold" options.

Rebas of that vintage share dampers with the Recon, but get the leg up with dual-air spring. Pretty sure my '13-ish (whatever the last year of dual air spring was) Reba uses excatly the same Motion Control dasmper unit as the '08 Recon it replaced.

The dampers themselves are nothing funky, basically a plastic canister with a rotary valve in the bottom opened & closed by a shaft connected to the lever on top. Remote lockout cartridges have a spring on the shaft to open the valve when the lock is released, non-remotes are not spring-loaded. "Motion Control" cartridges are designed in such a way as for the whole thing to be slightly compressible, so that when the valve is closed to stop oil flow, you still have a small amount of compliance rather than a rigid lock.

Remote-lock MC shafts can get sticky over time, typically manifested by the valve not properly opening because the spring can't override the friction on the shaft. It can be confused with a sticky cable, because the symptom is the same. Sadly, despite being such a simple contraption, the damper cartridge is pretty well unserviceable. Fortunately, very easy to replace, and I believe modern Recons still use essentially the same damper, although the shaft spring for remote versions is reversed, so the default position is locked instead of open.
Great post @The Duckmeister. Good thing some backward compatibility even if RS didn't really intend that to happen. Old RS parts still seem to be out there.
 
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