Go Back  Bike Forums > Bike Forums > Bicycle Mechanics
Reload this Page >

Help with an old broken shifter

Notices
Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

Help with an old broken shifter

Old 10-03-22, 12:22 PM
  #1  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Help with an old broken shifter

Hi,

I just got an old bike from a friend. The shifter for the front derailleur does not work, it does not lock the tension when pressed (the derailleur works OK), which means that I can only use the smallest gear in the front derailleur. The problem is that the system uses Shimano total integration brake levers/shifters Exage 300 LX, which I could not find anywhere (only the derailleurs can be found on eBay). I suppose I have to change the full brake/shifter system, but I have no idea about the compatibility of newer Shimano shifters/brakes with my bike (I would rather not change the brakes and derailleurs themselves as they work fine). Sorry, all this is new to me. Could you give me some advice on what to buy to fix the problem?

Kind regards.
Tealc.
Tealc is offline  
Old 10-03-22, 12:37 PM
  #2  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,252

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1546 Post(s)
Liked 844 Times in 609 Posts
FIRST!
Flush the innards with WD-40 or a similar solvent to dissolve the old, hard grease so the pawl can release.
Let sit for a bit and then slowly work the lever to the top gear position and slowly back down.
Repeat 3-4 times.
Bill Kapaun is offline  
Likes For Bill Kapaun:
Old 10-03-22, 12:45 PM
  #3  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Originally Posted by Bill Kapaun View Post
FIRST!
Flush the innards with WD-40 or a similar solvent to dissolve the old, hard grease so the pawl can release.
Let sit for a bit and then slowly work the lever to the top gear position and slowly back down.
Repeat 3-4 times.
Thanks for the quick reply. Yesterday I opened the shifter but the access to the interior was quite limited (for some reason it cannot be disassembled without removing the cable attached to the derailleur). In any case, I will do as you suggested, maybe the lever lock is stuck in unlocked position due to old grease. However it looked quite clean inside, no grease, so somebody might have done that before with no luck. Any other idea in case that fails to work?

Last edited by Tealc; 10-03-22 at 12:54 PM.
Tealc is offline  
Old 10-03-22, 01:26 PM
  #4  
VegasTriker
Senior Member
 
Join Date: Feb 2006
Location: Sin City, Nevada
Posts: 2,732

Bikes: Catrike 700, Greenspeed GTO trike, , Linear LWB recumbent, Haluzak Horizon SWB recumbent, Balance 450 MTB, Cannondale SM800 Beast of the East

Mentioned: 18 Post(s)
Tagged: 0 Thread(s)
Quoted: 490 Post(s)
Likes: 0
Liked 188 Times in 146 Posts
I had to look up what a Shimano Exage 300 lx was. The pictures and explanations are a 3X7 with Rapidfire shifters. It isn't an expensive model and still appears to be available. Your replacement just needs to be Shimano compatible and have 7 speed indexed shifting for the rear derailleur. There is a YouTube video on how to fix one
You can find a pair of replacements on eBay or Amazon. Examples:
$18 postpaid https://www.ebay.com/itm/175252024360
There are similar ones on Amazon but the sellers do not specify Shimano compatible so you might want to ask that question before selecting a pair to buy'
VegasTriker is offline  
Old 10-03-22, 01:37 PM
  #5  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,252

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1546 Post(s)
Liked 844 Times in 609 Posts
Originally Posted by VegasTriker View Post
...... Examples:
$18 postpaid https://www.ebay.com/itm/175252024360
There are similar ones on Amazon but the sellers do not specify Shimano compatible so you might want to ask that question before selecting a pair to buy'
And you know for sure the OP has V brakes?
Bill Kapaun is offline  
Old 10-03-22, 01:45 PM
  #6  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Originally Posted by Bill Kapaun View Post
And you know for sure the OP has V brakes?
Thank you all for your help. It would be much easier if I could post pictures! I cannot because I am new to the forum.

My shifter is not so easy to disassemble as in the video, but I could try harder next time, now that I saw what could be the culprit.

Regarding the purchase of new ones, I will check if I can get those you mentioned, but here in the UK.
Tealc is offline  
Old 10-03-22, 01:58 PM
  #7  
Bill Kapaun
Really Old Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Posts: 13,252

Bikes: 87 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.

Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 1546 Post(s)
Liked 844 Times in 609 Posts
https://www.sheldonbrown.com/gloss_ca-g.html#cantilever
https://www.sheldonbrown.com/gloss_da-o.html#directpull

Better determine the brake type because they use different amounts of cable pull.
Bill Kapaun is offline  
Old 10-03-22, 02:07 PM
  #8  
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,480

Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter

Mentioned: 130 Post(s)
Tagged: 1 Thread(s)
Quoted: 4613 Post(s)
Likes: 0
Liked 493 Times in 331 Posts
Don't waste any time shopping or fretting about compatibility until you've given Bill"s "Flush and work in" advice a good test. These shifters use an escapement controlled by a very light spring. The least mount of internal stickiness causes the problem you're experiencing. So, fo the flush, and light a candle to whatever gods favor your bikes.

Of course, you may be SOL, but you can cross that bridge when you get to it.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN

WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FBinNY is offline  
Likes For FBinNY:
Old 10-03-22, 02:19 PM
  #9  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Good! I'll try tomorrow. Maybe a bit of electric contact cleaner first, then WD40. My only concern is the lack of clear access to the internals, so I cannot give a good shake to the mechanism with a wire like in the video. Many thanks for your help, I'll post some feedback after tomorrow (hopefully).
Tealc is offline  
Old 10-03-22, 02:58 PM
  #10  
andrewclaus
Senior Member
 
Join Date: Feb 2012
Location: Golden, CO and Tucson, AZ
Posts: 2,585

Bikes: 2016 Fuji Tread, 1983 Trek 520

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 594 Post(s)
Liked 475 Times in 312 Posts
About two minutes into the video above shows the crux of the matter. The spring-loaded ratchet pawl is probably frozen on its shaft, and WD-40 isn't a good solution for that. If you need to pull the cable to remove the cover on your model, go ahead and do it--it'll be worth it. Then put a small squirt of penetrating oil on the pawl, and use a dental pick or homemade tool like in the video and work it for a few minutes until it's free. I do this nearly every week in the non-profit shop where I volunteer.

Sometimes WD-40 works by itself. As said above, light a candle and if you've lived a good life maybe it will work.
andrewclaus is offline  
Old 10-04-22, 10:14 AM
  #11  
dedhed
SE Wis
 
dedhed's Avatar
 
Join Date: Apr 2005
Location: Milwaukee, WI
Posts: 9,413

Bikes: '68 Raleigh Sprite, '02 Raleigh C500, '84 Raleigh Gran Prix, '91 Trek 400, 2013 Novara Randonee, 1990 Trek 970

Mentioned: 36 Post(s)
Tagged: 0 Thread(s)
Quoted: 2299 Post(s)
Liked 2,431 Times in 1,506 Posts
Originally Posted by Tealc View Post
Good! I'll try tomorrow. Maybe a bit of electric contact cleaner first, then WD40. My only concern is the lack of clear access to the internals, so I cannot give a good shake to the mechanism with a wire like in the video. Many thanks for your help, I'll post some feedback after tomorrow (hopefully).
Make sure any contact cleaner is "plastic safe"
dedhed is offline  
Old 10-04-22, 02:33 PM
  #12  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Thanks for all your guidance and support. Today I removed the cable and fully opened the shifter. It had some sticky stuff, but somebody had tried to remove it because it was not so bad and it had other oil in it. I did a more thorough job by sparingly using the contact cleaner and a cloth until all the small locks moved freely. The levers started working as expected, and after the contact cleaner was evaporated, I used WD40 and moved the mechanism many times up and down. Then I added thin lubricant oil (3 in 1 type for sewing machines) and reassembled the cable (a bit of a pain!). The shifter goes up the three gears (front derailleur) perfectly, but when I try to go down 1 step from the big gear (to the medium gear), it seems to do only half of the movement that it should, and the chain does not move to the medium gear (it just starts rubbing the derailleur). Pressing the shifter again moves the chain to the small gear correctly. But when going in the other direction, the shifter does the right amount of movement and the gears shift correctly at all the steps. I might have not cleaned everything fully, but I think it was correcly working for all the steps before assembling the cable. In any case, a minor problem and a big saving not having to buy new brakes/shifters. Thanks again!

P.S. Yes, the contact cleaner is just some type of alcohol, i.e.plastic safe. What it is dangerous is the typical brake cleaner, which is an organic solvent like acetone (it kills plastic, rubber, etc).
Tealc is offline  
Old 10-04-22, 02:49 PM
  #13  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 16,756

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Srewart 650B ATB

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3639 Post(s)
Liked 2,582 Times in 1,621 Posts
I don't recall if these front shifters had a trim feature, some of the early Shimano units did, most all modern versions don't. I have seen gummy and flushed/lubed trim featured shifters that the trim was so subtle a position that the trim didn't consistently work.

My go to solvent had been Safety Klean stuff. Now that NY state has banned that solvent I find it takes longer and more cycles of flushing before the gummy stuff is gone. Compressed air can be your friend BTW during this procedure. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Old 10-07-22, 06:32 PM
  #14  
oldbobcat
Senior Member
 
oldbobcat's Avatar
 
Join Date: Jul 2005
Location: Boulder County, CO
Posts: 3,793

Bikes: '79 Gios, '80 Masi, '06 Felt, early '60s Frejus

Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 298 Post(s)
Liked 242 Times in 185 Posts
This isn't brain surgery. Don't be afraid to make a mess.
oldbobcat is offline  
Old 10-08-22, 04:28 PM
  #15  
Tealc
Newbie
Thread Starter
 
Join Date: Oct 2022
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked 0 Times in 0 Posts
Brake cleaner contains very strong substances that dissolve/damage any organic component, including many plastics. When I opened the shifter, it had a couple of plastic parts. I would not use a brake cleaner that is not plastic safe. It may work better in short term, but it will damage the shifter after some time (depending on the plastic type an the brake cleaner composition, of course). It is like a lottery!
Tealc is offline  
Old 10-08-22, 09:43 PM
  #16  
Andrew R Stewart 
Senior Member
 
Andrew R Stewart's Avatar
 
Join Date: Feb 2012
Location: Rochester, NY
Posts: 16,756

Bikes: Stewart S&S coupled sport tourer, Stewart Sunday light, Stewart Commuting, Stewart Touring, Co Motion Tandem, Stewart 3-Spd, Stewart Track, Fuji Finest, Mongoose Tomac ATB, GT Bravado ATB, JCP Folder, Srewart 650B ATB

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3639 Post(s)
Liked 2,582 Times in 1,621 Posts
Originally Posted by Tealc View Post
Brake cleaner contains very strong substances that dissolve/damage any organic component, including many plastics. When I opened the shifter, it had a couple of plastic parts. I would not use a brake cleaner that is not plastic safe. It may work better in short term, but it will damage the shifter after some time (depending on the plastic type an the brake cleaner composition, of course). It is like a lottery!
True but- Most of the plastics in the history of Shimano STI lever internals is reasonably solvent resistant. I've left many shift pods (road and MtB) in a few solvents with no problems, including the ones from the 1990s that first showed gummy factory lube problems. I know of a few shifters I have reserviced years later (good customers and record keeping sometimes are a good thing) for a second time with no plastic/solvent issues. BUT there is one exception I will mention.

In the mid 1990s there was a version/series that had the shifter (Shimano MtB) enclosed in two plastic clam shell halves with a narrow "sealing" plastic "ring" between the two halves. This cover sealing ring was made of a softer/more flexible plastic then the half shells were. This ring seal would swell with solvent (Safety Kleen in the shops I worked at) and noy be able to be reinstalled with the seals and shell contact edged staying overlapped as OEM did. The solution was to remove the sealing ring before any flushing/cleaning. Of course this means removing the more stable plastic shell halves from the shifter pod and that seal, a lot more work then most will want to try. Andy
__________________
AndrewRStewart
Andrew R Stewart is offline  
Likes For Andrew R Stewart:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.