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The front shifter is a Shimano integrated brake-and-shift assembly. The front derailleur "groupo" is Shimano SIS. I can pull the cable to make the derailleur shift into third but the shifter doesn't have "enough throw" to do it via the shifter.

Pulled the cover off and threw some lube in it and it appeared to look just fine, but didn't take the closest of looks before having to shutter the shop.

First and second work just fine. Shifts up, shifts down.

Any ideas?

Thanks in advance.

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    It sounds like your cable is too loose... if you pull the cable (if accessible between cable housing sections) does it throw onto the large chainring? If so you likely need to tension the cable. If it doesnt the limit screws may need adjusting. – dafew Apr 12 '17 at 19:57
  • Did you try tightening the barrel adjuster? – Daniel R Hicks Apr 17 '17 at 11:55
  • Screwed it all the way in and re-tensioned the cable. I wonder if cable routing is an issue too? There is a cable guide attached to the BB and it looks... weird. It's oriented to face the chain stay and looks like a metal pulley (not plastic and on the underside of the BB). But that's not what's strange. The cable makes an "X" routing around the cable guide. I'd have thought it'd just make a "U" around the guide then attach to the derailleur... – mcwagner Apr 18 '17 at 16:01
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    Cables slowly stretch over time. And as a cable approaches end of life it begins to stretch more rapidly. – Daniel R Hicks May 13 '17 at 11:18
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Cable tension

Limit Screws

Derailleur position/angle

These are the only things that actually affect your shifting mechanically. If those are all proper, something is broken/misaligned/shredded.

  • Positioning might make sense. I'll make sure it's aligned correctly when I get it into the stand next. I re-tensioned the cable and set the limit screws. – mcwagner Apr 18 '17 at 16:05
  • @mcwagner Did it work? – CardMechanic May 12 '17 at 20:36
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Having had exactly the same problem I tracked it down to the shifter, and as a previous contributor stated it is the manufacturer’s grease that gets sticky and stops smooth operation. There is a ratchet mechanism in place with a small metal pawl which has a weak spring. The sticky grease stops the pawl (little metal square which engages notches or steps in the main part when the shift leaver is pushed across) from engaging the third notch, it almost drops in but not quite. Fully degreasing the innards of the shifter and then spraying with T85 got ing working smoothly.

  • Welcome to the site! – David Richerby Sep 4 '18 at 9:53
  • In this case, pulling the visible inner cable by hand would have shown the derailleur to work normally, isolating your problem to the shifter. – Criggie Jan 7 '19 at 18:19
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the grease inside of the shifter has gone bad. It goes all sticky instead of slidey and the clicker gets stuck. De grease and re grease the shifter.

  • Isn’t this one of the very few places where grease is bad? Use very light lube or maybe even WD-40. – Michael Aug 28 '17 at 11:18
  • The metal parts inside the shifters come already greased When they are new. I don't know what grease they use but it gets sticky over time. What I do know is that many types of grease degrade plastics. I use boeshield T9, not exactly a grease, it forms a waxy coating that lubricates and protects from corrosion and won't harm plastic. I wouldn't use wd 40 because it's a penetrating and displacing agent not a lubricant. Use it to loosen up and clear out the old sticky grease but use another product to lubricate. – Mr Ed Aug 30 '17 at 3:58
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But you did not mention, how this happened? Is this a new bike, or did you change the cable? Did this shifter work fine in the past?

I think there is some problem with the basic cable tension, if it is not set up properly then the 3rd gear could be a problem. Try to find a youtube video, where they explain how to set it up properly, it's not that hard, just need some practice/patience.

  • Old bike. Existing cable. It's a friend's bike who they've gotten second-hand. As far as I know this was baseline from initial build from Wal-Mart (or whomever initially sold the bike). – mcwagner Apr 18 '17 at 16:04
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The shifter has two size cogs in the centre. The first activates 1st and 2nd. To activate the third gear, a spring pulls the lever bar towards the centre (smaller cog). The spring isn't very strong and will stick, not pulling it in and therefore not catching the cog. Clean the area of the spring. I just use oil.

It is the same mechanism with more cogs, for the other shifter for the gears on the wheel.

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From what it looks like, it can be the derailleur angle affecting the shifting to the third chainring or, it can be that your derailleur cage has suffered damage and is out of shape or shaved. You can rule out the limit screws if the shifter is getting to the third index, as you've said it is. The cable tension is another possibility but since the other two shifts are good, it's unlikely that's the issue. I recommend you get the bike to your LBS to get it sorted out if you have troubles diagnosing the problem. Just appraise your derailleur cage and it's angle wrt to the chainrings before that, it's likely you get to the root once you do that. And yeah, the cage should be approximately parallel to the chainrings, you know what's wrong if it's not. I hope this helps. :)

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