Repair guides › Drivetrain
3x shifting and chainring care
Three front rings (e.g. 48/38/28 or 42/34/24) with a front derailleur. Common on budget mountain bikes, older hybrids and touring bikes: a very wide range with small steps. The middle ring covers most riding; the small "granny" ring is for steep climbs; the big ring for speed on flats. A triple needs a front derailleur and shifter made for 3 rings, and a long-cage rear derailleur to take up the extra chain.
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Tools
- Ball-end hex key set (1.5–10 mm): Park Tool HXS-1.2 Professional L-Shaped Hex Set ($$)
- JIS #2 screwdriver: Vessel Megadora JIS screwdriver #2 ($)
- 1/4" click torque wrench (about 2–17 Nm) + bits: Pro Bike Tool 1/4 inch drive click torque wrench set (2.2–16.9 Nm) ($$)
- Shop rags + nitrile gloves: shop towels and nitrile gloves ($)
Compare Good, Better and Best for each tool
Steps
- Clean and inspect all three rings; the middle ring wears fastest.
- Set the front derailleur's L screw on the granny ring and the H screw on the big ring, then cable tension so the middle ring shifts cleanly.
- Use the middle ring with most of the cassette; the granny ring with the big cogs only; the big ring with the small cogs only.
- Check ring bolts (current Shimano 12–14 Nm; 16–17 Nm on the granny ring; check the crank maker).
Torque
| Fastener | Torque |
|---|---|
| Chainring bolts | 12–14 Nm on current Shimano cranks (16–17 Nm small ring); check crank maker |
Diagram
Side view, chain side toward youChainrings
Signs it needs doing
- Chain drops off the granny ring onto the frame
- Will not shift onto the big ring
- Rubbing in many gears
- Middle ring teeth worn first (it does most of the work)