Problems Indexing on a 1x9

Blunderbuss

Pedelecer
Mar 11, 2018
157
22
Cambridge
I have got a problem in getting the indexing to work on a 1 x 9. I was riding for 90% of the time in the middle gear on the front and 10% on the smallest (22/32/42 as per standard on Carreras) so the 42 never got used. Also the mud would clog up the front mech, so I decided to get rid of it and replace the back cassette with a 11/40 (11/32 is standard). The spread of gears on the 11/40 with a 32 up front is perfect with the geared rear hub for what I do. (I have left the 22 on the front so I can change to that manually if i ever have any motor problems)

But no matter how I adjust the derailleur it will not index consistently between gears 4,5 and 6. With it setup as best I can it will miss every 3rd or 4th change in both directions, but when you index again it then jumps 2 (so catches up with itself). The chain line is straightest when in 4th/5th gear so that all looks nice and it’s a new chain as well, the cassette came with a small extender that drops the derailleur a bit lower which I fitted.

The derailleur is a Shimano Altus, so I was thinking that it may not be “man enough” for the job, but the jumps between 4,5 and 6 are nothing like as big as those between 7 & 8 and 8 & 9 which it indexes perfectly.

Any thoughts welcome.

01012019.jpg
 

soundwave

Esteemed Pedelecer
May 23, 2015
9,000
3,740
no idea but it must have at some point as could not index the gears until i changed it tho they are meant to bend and snap.
 

scott gaza

Pedelecer
Oct 20, 2018
51
11
scone
Hi Blunderbuss, Just a note that a chain wants to run straight, so without causing excessive wear on running gear. The 40t would line up with the 22t and the 11t to the removed 42t and are used to minimize wear on the system. Looks to me that your running your bike on 9 gears forcing chain past optimal running line, with the small extender that drops the derailleur fitted exaggerating the wear to the running gear or bent hanger.
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,595
5,691
The European Union
Hi Blunderbuss, Just a note that a chain wants to run straight, so without causing excessive wear on running gear. The 40t would line up with the 22t and the 11t to the removed 42t and are used to minimize wear on the system. Looks to me that your running your bike on 9 gears forcing chain past optimal running line, with the small extender that drops the derailleur fitted exaggerating the wear to the running gear or bent hanger.
Yeah I was going to say the derailleur extender might be the culprit. Best having a derailleur that can handle the gears than using an add on. I had no problem with the derailleur clearance when I put an 11-40 on. I can't comment on chainline problems, on a trike that is not a thing...
 

Blunderbuss

Pedelecer
Mar 11, 2018
157
22
Cambridge
Hi Blunderbuss, Just a note that a chain wants to run straight, so without causing excessive wear on running gear. The 40t would line up with the 22t and the 11t to the removed 42t and are used to minimize wear on the system. Looks to me that your running your bike on 9 gears forcing chain past optimal running line, with the small extender that drops the derailleur fitted exaggerating the wear to the running gear or bent hanger.
Yes it is a 9 gear, the front 32 is the middle so across the back 11 to 40 it produces the least bad alignment (for gears 4,5,6 it is almost straight in line), so i am hoping of the options i have it should not be any worse than the bikes original setup.

The bent mech is certainly a possibility that i will look at, and that extender will also get some attention now.
 
Last edited:

Blunderbuss

Pedelecer
Mar 11, 2018
157
22
Cambridge
Yeah I was going to say the derailleur extender might be the culprit. Best having a derailleur that can handle the gears than using an add on. I had no problem with the derailleur clearance when I put an 11-40 on. I can't comment on chainline problems, on a trike that is not a thing...
I don't think the chain line is an issue because it is no different from how the bike is sold from Halfords,
(whilst the diameter of the gears has changed the location has not) - but the extender could be a very different issue, because it was in the box I just fitted it!!! It is supposed to make sure that the derailleur clears the bigger diameter of the 34 and 40 gears (corresponding to 28 and 30 on the stock) but i never checked if it would clear without :rolleyes:. Will be doing that next - thank you.
 

Kinninvie

Esteemed Pedelecer
Oct 5, 2013
888
399
Teesdale,England
Anyone know where I can buy one of those Park Tools rock from? ;)
 

awol

Esteemed Pedelecer
Sep 4, 2013
1,114
337
Anyone know where I can buy one of those Park Tools rock from? ;)
Direct from Parktool. Its the PR1 (Parktool Rock 1) and a bargain for about £100. I've got genuine spare ones here you can have for only £20 though if you want.
rock.jpg
 

Charliefox

Pedelecer
Feb 11, 2015
207
49
74
Culloden Moor Inverness
I have got a problem in getting the indexing to work on a 1 x 9. I was riding for 90% of the time in the middle gear on the front and 10% on the smallest (22/32/42 as per standard on Carreras) so the 42 never got used. Also the mud would clog up the front mech, so I decided to get rid of it and replace the back cassette with a 11/40 (11/32 is standard). The spread of gears on the 11/40 with a 32 up front is perfect with the geared rear hub for what I do. (I have left the 22 on the front so I can change to that manually if i ever have any motor problems)

But no matter how I adjust the derailleur it will not index consistently between gears 4,5 and 6. With it setup as best I can it will miss every 3rd or 4th change in both directions, but when you index again it then jumps 2 (so catches up with itself). The chain line is straightest when in 4th/5th gear so that all looks nice and it’s a new chain as well, the cassette came with a small extender that drops the derailleur a bit lower which I fitted.

The derailleur is a Shimano Altus, so I was thinking that it may not be “man enough” for the job, but the jumps between 4,5 and 6 are nothing like as big as those between 7 & 8 and 8 & 9 which it indexes perfectly.

Any thoughts welcome.

View attachment 28336
One thing you might consider is 'is the gear hanger bent a bit?' I had endless trouble on one of my bikes and decided to buy an X-Tools Pro Gear Hanger Alignment Tool from Chainreaction. You can read the buyers comments about it. I could not believe how far out my hanger was (7-8mm!) but it was not noticeable by eye. After putting it right I had a bit more fiddling with gear cable length and oiling then had excellent gear changes. I expect to check it after ant tumbles on the trails. Having a collection of 10 bikes for the family I can justify the modest £19.99 paid for it.
 

Laser Man

Pedelecer
Jul 1, 2018
93
50
Michelmersh SO51
I had an Altus rear mech on my old bike and had similar problems.
The hanger was OK, but the bearing bush which screws into the hanger allowed the mech to wobble about.
I changed it to a Deore mech (which is much better engineered) and the problem went away permanently.
 

Blunderbuss

Pedelecer
Mar 11, 2018
157
22
Cambridge
Yeah I was going to say the derailleur extender might be the culprit. Best having a derailleur that can handle the gears than using an add on. I had no problem with the derailleur clearance when I put an 11-40 on. I can't comment on chainline problems, on a trike that is not a thing...
I got time to try without the extender to see, but in my setup the idler gear doesn't clear the 40 tooth - although it did work better on 4,5 and 6!!
20190106_130156.jpg

I have the alignment tool on order so that is the next thing (thanks Charliefox), but as it has problems indexing in both directions i'm not sure this is the problem; but I want the tool anyway. I tried to make one following some good youtube builds, but the thread on the hanger is not something i could find a bolt or threaded bar to fit - it is a very fine pitch so that project failed very early :rolleyes:

Having messed around with the Altus a bit more it seems as if it just needs a little more "push" to get the next gear to engage - maybe the spring/components inside of it is just not good enough as Laser Man said.
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,595
5,691
The European Union
I'm going to fit a Deore on the trike as soon as I have the funds, indexing the Alivio almost drove me nuts. The Acera on my pedelec is bulletproof which just goes to show a cheap entry level derailleur can do a good job.
 

scott gaza

Pedelecer
Oct 20, 2018
51
11
scone
Shame about that! I would tend to go for a long reach derailleur so not to use extension, but only if the alignment tool does not work, and possibly a new inner wire.
 

Laser Man

Pedelecer
Jul 1, 2018
93
50
Michelmersh SO51
The Deore mechs have much bigger/stronger return springs than the Altus and Alivio equivalents, in addition to being generally much better engineered.
I got mine from Amazon : cheapest I could find anywhere at £27.50. It will do up to 9 speed. (Deore RD-M592, long cage)
 

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