Indexing question

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steveindenmark

Legendary Member
Improving my bike maintenence knowledge is on my New Years resolution list.

In the meantime I could use some help.

I have a Cannondale 10 speed racer with 105 gearing. When I shift the gears on the rear cassette the shifter clicks for the first 4 gears but the chain does not move. On the 5th click it moves to the small cassette ring. The gears shift correctly for the next 5 gears and then will not shift anymore. The chain will not move onto the last 4 large cassette rings.

Could someone offer some advice please?
 
Cables?
 
Location
Essex
Your cable's not taut until the 5th click by the sounds of it (assuming the 5th click moves from the smallest sprocket to the next smallest?)

If I read that correctly then you need to wind the barrel adjuster by the rear derailleur in, put it in the smallest sprocket, loosen the cable clamp, pull the cable taut then retighten the clamp. If the first click doesn't induce the chain to move to the next sprocket, turn the barrel adjuster anti-clockwise a bit until it does. Could be time for new cables too...

 

Smokin Joe

Legendary Member
It sounds very much like the cable has been fitted while the chain was on one of the middle sprockets. Shift all the way down and then click the shifter at least four more times (To get it on it's bottom click) then re-clamp the cable making sure you have pulled it taught. It may not shift when you then give it the first click or two but that should be easy to sort with the barrel adjuster (Which you should make sure is turned fully clockwise before you reconnect the cable).
 

Ian H

Ancient randonneur
Check first that the cable is in good condition. They often start to fray at the lever end.
Move the lever to the highest gear/smallest sprocket, right to the last click. You will probably see that the cable has quite a bit of slack. Screww any adjusters most of the way in. Slacken the clamp holding the cable at the rear mech and pull the cable through as tight as you can, re-tighten the clamp. Now try the gears. They should be nearer to a full range, but you will probably have to use the adjusters to finish the job.
 

straas

Matt
Location
Manchester
I came on to post a near identical question!

On a Shimano 105 rear derailleur I can only get the middle 7 gears on an 11sp cassette.

Tried shifting into lowest, adjusting the h screw and pulling the cable taught (though the cable didn't really move)

I can manually move the derailleur to go through the gear range, so assuming the hanger hasn't been bent.

Would it be a sticky cable around the shifter?
 

raleighnut

Legendary Member
I came on to post a near identical question!

On a Shimano 105 rear derailleur I can only get the middle 7 gears on an 11sp cassette.

Tried shifting into lowest, adjusting the h screw and pulling the cable taught (though the cable didn't really move)

I can manually move the derailleur to go through the gear range, so assuming the hanger hasn't been bent.

Would it be a sticky cable around the shifter?

The H and L screws don't affect indexing, they are limit stops to prevent the rear mech from overtravelling and dropping the chain either into the spokes or off the end.
 

chriscross1966

Über Member
Location
Swindon
I came on to post a near identical question!

On a Shimano 105 rear derailleur I can only get the middle 7 gears on an 11sp cassette.

Tried shifting into lowest, adjusting the h screw and pulling the cable taught (though the cable didn't really move)

I can manually move the derailleur to go through the gear range, so assuming the hanger hasn't been bent.

Would it be a sticky cable around the shifter?
Sounds like your limit screws are set too far in at both ends
 

straas

Matt
Location
Manchester
If all the gears can be accessed manually it can't be the limit screws.

Yeah, I'm pretty confident I've got the limit screws set correctly - only adjusted the H screw slightly so the jockey wheel was directly under the cog.

Just strange that it's limited the gear range - I also need to shift a couple of times to actually feel some positive resistance on the shifter. I'm guessing the cable is sticking somewhere, but not sure where...
 

raleighnut

Legendary Member
Yeah, I'm pretty confident I've got the limit screws set correctly - only adjusted the H screw slightly so the jockey wheel was directly under the cog.

Just strange that it's limited the gear range - I also need to shift a couple of times to actually feel some positive resistance on the shifter. I'm guessing the cable is sticking somewhere, but not sure where...

I'd fit a new inner and also replace the short bit of outer that links the rear mech to the frame, notorious for causing problems.
 

boydj

Legendary Member
Location
Paisley
The OP problem is lack of cable tension. STIs are prone to fray inside the shifter, so I'd start with a new inner cable. Changing the last bit of outer is good advice as well. Once the new inner is installed, follow the guidance above to get the shifting working properly.
 
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