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I’ve got a couple of problems here. I don’t know if they are all related. Problem 1: it doesn’t always shift into the big ring in front. Usually, I have to slow my pace down for it to catch and also go to the biggest cog. But that still only works sometimes.

Problem 2: The chain won’t go to the largest big in the back when I try to get there. It doesn’t matter which front ring I’m on.

Problem 3: Similar to problem 1. When I go down to the smallest cog, the chain falls of and goes between the smallest cog and the frame. Basically, everything is shifted one to the right.

Any solutions? The bike wasn’t very expensive to start with. (Surprise, surprise). It’s more cost effective to fix it myself than to take it to a bike mechanic.

Gabriel Yopack
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As Criggie said in his answer you basically just need to adjust both the front and rear derailleurs. This is well within the capabilities of a home mechanic if you know what you are doing. Trick is knowing about limit adjustments (prevents the derailleur moving too far in or out) and indexing adjustments (aligns the derailleur over the sprockets or chainrings. What really helps is a article or video that walks you through the process step by step. Park Tool has particularly good ones that are clear and easy to follow.

Rear derailleur (do the rear first): https://www.parktool.com/blog/repair-help/rear-derailleur-adjustment

Front derailleur: https://www.parktool.com/blog/repair-help/front-derailleur-adjustment

Argenti Apparatus
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Answer 1 - Your front inner cable is too long, or the high limit screw is too close and stops the front mech from moving over enough. A sometimes problem like this might be solved by a single turn of a barrel adjuster, if one is installed on your front mech cable. Try hanging the bike up and manipulating it by hand to get a feel for the problem.

Answer 2 - your rear inner cable is too long and has slack in it when in top (hardest) gear. It has probably stretched and settled over time, increasing its effective length by a couple of millimetres. This can be adjusted with the Barrel adjuster, but if you run out of length then you'll need to pull some cable through the pinch bolt on the rear mech.

Answer 3 - your high limit screw is wrongly positioned. It should stop the mech from over-reaching like that. If you fixed this limiter, then there will remain a ghost click at that end of the shifter.

UPSHOT you have three separate but similar and related problems going on. Fix each bit one at a time. You can do this easier slow-pedalling with one hand while the bike is off the ground. A workstand is nice, but some rope and a tree branch or rafter works adequately too.

Criggie
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