bboy314

I recently required a bike that is probably about ten years old with Shimano RSX 8-speed components. The bike obviously was barely ridden and everything's in great shape, but both shifters are having issues. They will both shift up, but not down. As in the larger brake lever shifts, but the smaller lever doesn't shift or even click or move the cable at all, although I can push the lever in. The levers were doing this when I got them, and they felt gunky probably from old caked-up grease, so I've been flushing with wd-40 and tri-flow. This has made them feel better shifting up, but still no action shifting the other way. It almost seems like they've been somehow set into one speed but I'm not sure if that's possible.

My next step will be taking the levers apart as I've heard it's doable with these old 8 speeds. However if anyone has any input into this particular problem it would be greatly appreciated.

Thanks,

Brian

jasonrobo02

Are the cables hooked to the derailleurs? I only ask because I've had STI levers before that wouldn't shift with the small lever while off the bike, but as soon as you gave them some resistance by either pulling on the cables or hooking the cables to derailleurs, they would work great in both directions.

Kimmo 

If they don't suddenly work with a bit of cable tension, it sounds like you have to take em apart.

Good luck.

Mr. Embrey

You have to manually wiggle the ratchet thing a bit. It's right on top underneath the plastic cover. I had to snap mine off. Shift it a couple times while looking inside it, you'll figure it out eventually.

bboy314

Yeah, no luck, these were doing the same thing when they were hooked up. I tried again putting tension on the cables, but no dice. I'll try to wiggle the ratchet thingy too. Kimmo, I've already been studying your guide at great length, so soon it will be time to dive in. Thanks for posting that!

dddd

Mr. Embrey makes a valuable contruibution to shifter-fixers.

Many shifters have flexible plastic covers that allow a peek inside, and with the help of a small screwdriver you can manually actuate the sticking pawl.
You have to have some idea what a pawl looks like or figure this out, but once you can move it with some motor oil (not WD40 and not Tri-Flow, both are short-lived before they re-gum) it will free up nicely with repeated movement.
This process can be accelerated by warming the entire mechanism, and in fact warming it up usually gets everything clicking, at least long enough to work some oil into the pawl's pivot.

Alternatively, my guaranteed-lasting solution for these levers is not to dis-assemble but rather to remove the hoods then drop the shifters head-first into hot motor oil for an hour.

Note you can heat the oil by putting a 4"-diameter coffee can or yogurt canister with 2" of oil in it inside of a larger bowl
that has a quart of boiling water in it then cover the whole thing with several grocery bags for insulation.

The levers will get hot, and if you want to be able to handle them while shifting them during the soaking period you'll need gloves. Work them thru the gears (they'll be all freed up after 1/2 hour) then return them to the oil for another 1/2 hour before thaking them outside (still hot) and whirling them on a stout bungee or such to extract all excess oil.

Finally they need to be wiped down thoroughly with a terry towel and/or sprayed lightly with some spray solvent to get all the external oilyness under control before re-fitting the rubber hoods (moderately difficult in itself, use alcohol as a lubricant).

The shifters will now be ready for years of cold-weather service.
Note that disassembly usually results in shifters that never again see the light of day.

slushlover2

I have never bought a bike with RSX shifters that worked. I also have never had them that I couldn't get working by flushing and relubing. I let them flush in a solvent tank and lube with Triflow. I have done dozens this way.
The non working shifters are a great bargaining tool when buying bikes!!!

Kimmo 

Yeah, sorry about the blurry pics... the descriptions prolly don't make much sense unless you're looking at the bits either, I guess. Hopefully the mechanism is identical...

But that hot oil tip sounds like it's worth a try first.

Mr. Embrey

Thanks, that's the word I was looking for. And I agree with the note at the bottom as well.

dddd

"I let them flush in a solvent tank and lube with Triflow. I have done dozens this way."

I used TriFlow for years. I especially liked the way aerosol TriFlow would expand like a foam to penetrate the entire shifter head immediately.

I did also notice that the resusitated shifters often gummed again a couple of years later. Your method of thorough solvent cleaning likely better prepared the pawl pivots for the TriFlow with no grease left behind to re-gum?

I Sometimes found shifters that had gummed so solidly (especially certain mtb versions) that the spray didn't work at all.
I also noticed that a later re-spray with TriFlow didn't work nearly as long as the first time.

After trying the hot-oil bath method I haven't had a shifter that wouldn't loosen and haven't had one re-gum the pawls.
It's a long-lasting repair but is of course much more time consuming also, so probably best for when the shifters are already off of the bike or for the second time around when thickened lubricants have built up.

Cynikal 

If this doesn't work out for you, I have a set of Sora 8speed shifters that are almost new. PM if interested.

DieselDan

Try spraying any chain lube in them before you even think of taking them apart. I had the same problem with some 7-speed levers, and treating them with lube brought them back to life perfectly, with some new cables and housings too.

eeforme

Did you ever get your brifters working?

https://sheldonbrown.com/sti-repair.html