Bicycle Mechanics - Shimano trigger shifters

Can Shimano trigger shifters be rebuilt? These are 770s, from about 2006.

Simple answer is no, only to the level shown in the Techdocs, which isnt very far

http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/SL/EV-SL-R770-2476_v1_m56577569830609221.pdf

These are pretty reliable, what has gone gone wrong with them? have used Rapidfire for 15+ years, and 770's for 4 with no issues

Both left and right have gone sticky. I'm not sure yet if it/s just cable/housing, or in the units.

The left one does not click into the big chainring position, and the thumbkey on the right does not slip back when you depress it. If I pull it back and forth, it will dump the chain from the big chainwheel to the smallest one.

Both left and right have gone sticky. I'm not sure yet if it/s just cable/housing, or in the units.

The left one does not click into the big chainring position, and the thumbkey on the right does not slip back when you depress it. If I pull it back and forth, it will dump the chain from the big chainwheel to the smallest one.

First step is to remove cables and check for excessive friction. You may need new outers.

Second stage is to fire some GT85 or similar into the shifter. Usually does the trick. As has been said above, they are generally very reliable units so I wouldn't imagine anything has gone too far awry.

What's GT85?

Try WD-40 or equivalent to "soften" the grease.

What's GT85?

This (http://www.google.co.uk/#hl=en&sugexp=llsfp&xhr=t&q=gt85&cp=3&pf=p&sclient=psy&aq=0&aqi=&aql=&oq=gt8&pbx=1&fp=fa51c521da8cc608).

It's basically WD-40 with PTFE, so it has some lubing properties.

There are a lot of parts in them. I have taken them apart, cleaned and re-greased them before, but as I mentioned - there are a lot of bits.

Before:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_03.jpg

After:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_04.jpg

Bits:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_02.jpg

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_01.jpg

Road Fan....If you send them my way I'll service them for free. Just cover the shipping to 33617

Jim, pm me your phone number, let's discuss it.

Miamijim, I am interested in what you suggest. How fast could you do them and get them back in the mail? I have a friend who wants to buy this bike from my wife, for his wife for Mothers' Day.

So I ahve to figure out how this fits into my time schedule, unfortunately. If it was just my project, no problem.

There are a lot of parts in them. I have taken them apart, cleaned and re-greased them before, but as I mentioned - there are a lot of bits.

Before:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_03.jpg

After:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_04.jpg

Bits:

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_02.jpg

http://i207.photobucket.com/albums/bb60/gerald_g/Bikes_etc/shifters_01.jpg

Yikes!! Thats amazing!! I would have settled for just dumping the assembly in an ultrasonic cleaner.

Top points for patience!!

Bumping.

So I picked up an older GT Outlook with a set of Rapid Fire Plus (RP+) shifters that won't ratchet. I got the price knocked down due to the no shifting and I really thought it would be a case of hitting them with some WD-40 (as I have done with many other bikes) and they would be good. I have hit them with WD-40 more than a half dozen times and the left shifter now will now do one of the two clicks. The right side will not catch, although I can pull on the cable and get it to shift one click and the finger controls are able to shift it back.

I am trying to think of something better than WD-40 to try before giving up on them. I don't think I would be great with tearing them down -- that is a lot of small parts. Worst case is I replace them with a set of friction thumb shifters, but I would prefer to have the RP+ style instead.

they can be re-built. after all, someone had to put them together in the first place right?

most of the time, it's not needed though. if you soak them in a heavy duty degreaser for a while and blast them out with compressed air, then apply some thin lube like Triflow, you should be able to get them going again. Clean Streak is a great shifter-liberator.

I bought some used XTR 952 triggers and they worked well except the right would be slow to reset after a multiple shift.
I would manually push it back to speed it up. It was annoying but since it was on the bike I rode the least I let it go.
It did seem to get worse as time went on and I contemplated replacing them, but I thought I would hit it with some
WD-40 to see what happens.
It basically made them function as new, and I would try this before you try taking them apart.
I have 22+ year old thumb shifters that still work fine (with ZERO maintenance).

I am trying to think of something better than WD-40 to try before giving up on them.

Send them my way and I'll service them for free. As long as nothing is broken I should be able to get them going. Pm me if your interested.