Missing 6th
#2
Senior Member
Joined: Mar 2005
Posts: 167
Likes: 0
Your dad likely adjusted the L-limit screw which allowed the derailleur to move inwards more and move the chain into 1st gear. Missing gears in the middle has to do with cable tension and can be adjusted using the barrel adjusters located at the shifters, derailleur, or both. Read the "Checking the Rear Indexing Adjustment" section here:
https://www.parktool.com/blog/repair-...nts-derailleur
The barrel adjuster on the derailleur looks like this:
https://bicycleswest.com/images/libra...erailleur1.jpg
I seem to only get this problem going 1 way (shifting from 5-6-7 is fine but 7-6-5 sometimes skips 6, results in a slow shift, or causes grinding). It is very easy to overdo barrel adjustments so remember to only make quarter turns.
https://www.parktool.com/blog/repair-...nts-derailleur
The barrel adjuster on the derailleur looks like this:
https://bicycleswest.com/images/libra...erailleur1.jpg
I seem to only get this problem going 1 way (shifting from 5-6-7 is fine but 7-6-5 sometimes skips 6, results in a slow shift, or causes grinding). It is very easy to overdo barrel adjustments so remember to only make quarter turns.
#4
Mechanic/Tourist
Joined: Apr 2007
Posts: 7,522
Likes: 12
From: Syracuse, NY
Bikes: 2008 Novara Randonee - love it. Previous bikes:Motobecane Mirage, 1972 Moto Grand Jubilee (my fave), Jackson Rake 16, 1983 C'dale ST500.
We're not there so can't tell what you've done correctly or incorrectly. Grinding noises and shifting problems can have multiple causes. If you go through the entire procedure for cables and derailleurs on the Park site and still have problems, we either need more details or you need to visit a shop.
#5
Thread Starter
Senior Member
Joined: Feb 2012
Posts: 237
Likes: 0
From: Nova Scotia, CANADA
Bikes: CCM 21 speed big box special.....
Ok I think it is just the H-limit and L-limit screws I need to adjust
I am now only missing 1st
I am now only missing 1st
Last edited by Wolfvegas; 07-22-12 at 06:19 PM.
#6
Thread Starter
Senior Member
Joined: Feb 2012
Posts: 237
Likes: 0
From: Nova Scotia, CANADA
Bikes: CCM 21 speed big box special.....
So I must do this yes! [h=3]L-Limit Screw[/h]The L-limit stops the derailleur from moving inward (toward the spokes). The limit screw does not make the derailleur move, pulling the inner wire makes the derailleur move. The L-screw allows the pulley wheels to shift the chain to the innermost sprocket and yet not shift off the sprocket into the spokes.
- Shift bike to middle chainring (or smaller ring of double chainring bikes) and to second-to-innermost rear sprocket.
- Pedal bike at a quick cadence, approximately 60 rpm or more.
- Pull inner wire by hand to shift derailleur sprocket inward. When adjusting the L-screw, be concerned with two situations:
- The inward shift from the second-to-innermost sprocket to the innermost sprocket.
- How the chain rides on the innermost sprocket.
- If shifting seems adequate, tighten L-screw 1/4 turn, and repeat shift. Continue to tighten L-screw until symptoms of too tight appear. These symptoms are that the chain will not complete shift even with pressure on inner wire, the chain hesitates before shifting inward even with constant pressure on inner wire, or the chain rattles excessively when riding on innermost sprocket

- When symptoms of a too tight L-screw appear, loosen L-screw 1/4 turn and check shift again. Repeat process of shifting and correcting by 1/4 turns. When too tight symptoms disappear, L-screw is at tightest acceptable setting, and limit screw setting is done.
#7
Thread Starter
Senior Member
Joined: Feb 2012
Posts: 237
Likes: 0
From: Nova Scotia, CANADA
Bikes: CCM 21 speed big box special.....
Im in rage mode, I don't want to pay to take it to a LBS the problem seems so simple yet I cannot fix it. I wanted to ride today but now im ragin.
#8
Thread Starter
Senior Member
Joined: Feb 2012
Posts: 237
Likes: 0
From: Nova Scotia, CANADA
Bikes: CCM 21 speed big box special.....
oh for ffs now when im on the outer chainring on the front and I hit 7 it goes totally off the gear, need a bike stand and a 2nd opinion me thinks





