The #1 Bicycle Mechanic Website in the World!


Cardio Trek Personal Trainer
Cardio Trek
Sports Trainer
East York, Toronto, ON
Hours: Tues-Thurs 10-5:30, Sat-Sun 10-3:30
Cardio Trek is best known for teaching archery lessons in Toronto.

Tuesday, August 6, 2013

12 Step Derailleur Tuning

Want to learn how to adjust and fix your derailleurs? Here is the 12 step program as set forth by Jerzy "Smokey" Dymny of the Quadra Bike School.

1. Rear derailleur. Shift to high gear (small ring) and disconnect DR cable. (If DR has a reverse-rise spring the DR travels in opposite direction when released. In that case reverse these instructions for high and low cogs.)

2. Set high limit screw. Chain must travel smoothly on smallest cog but not go past it.

3. Check the complete cable path and reconnect rear derailleur cable.

4. To tune rear shifting, shift chain to middle chainring in front & tighten rear barrel adjuster until each shift click produces one clean downshift in the rear.

5. Adjust the low limit screw to let the chain reach large (low) cog but not shift past it. Check guide pulley spacing and adjust “B” screw to increase spacing if necessary.

6. Test up shifts. Turn barrel adjuster slightly in, if any shift is slow. Repeat till perfect.

7. Leave rear DR in low (large). Disconnect front cable. Adjust height of front derailleur 1–3mm above large ring.  Set front DR low limit screw. Tightening low limit screw pushes derailleur outward from frame.

8. Check complete cable path. Reconnect front cable.  Leave front DR in small ring. Test rear DR shifts up to second highest cog.

9. Shift front DR to middle ring. Test rear DR shifts through all gears.

10. Place Chain/String tool on smallest rear cog and largest chainring. Rotate front cage to match the cage engagement gap to the string angle.

11. Shift to the large ring. Set high limit screw. Test rear shifting to second lowest cog.

12. Check that front derailleur shifts through whole range & downshifts quickly.

© 2012, Quadra Bike School

No comments:

Post a Comment


Spam comments will not be approved. If you want to advertise your product or service (or want to sponsor this blog) please send an email.

Popular Posts

Looking for a bicycle mechanic school in Canada? The Quadra Island Bike School in British Columbia is a Canadian bicycle mechanic school that trains professional bicycle mechanics against the backdrop of the beautiful Quadra Island.

About the Author

Charles Moffat is equal parts bicycle mechanic, cyclist, painter, sculptor, fantasy writer, poet, website designer and pun maker. For more details see



Do you own a bike shop and are looking to hire a bicycle mechanic in North America? Just email me with the job posting details and I will post it for you. (Also, please let me know when the job has been filled so I can update the posting.)


If your bicycle is basically junk and you don't know what to do with it then SELL IT TO ME. I will use it for parts. I will give you a fair price ($20 to $30) for your old clunker just so I can rip it apart for parts.

If you need repairs check out my Bicycle Mechanic Services in Banbury-Don Mills.