Retrobike Forum Index

It is currently Sat Nov 17, 2018 7:21 pm

* Login   * Register * Search  * FAQ



Post new topic Reply to topic  [ 15 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: Indexed Shifting Help.
PostPosted: Sat Aug 18, 2018 7:21 am 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
I'm trying to get a 7 speed Shimano 300EX rear derailleur to index using Exage sport shifters.

It seems I can either get the low range of the cassette shifting smoothly or the high range,but not across the whole range.

When I adjust the tension on the cable so that the chain will climb up onto the largest cog on the cassette it will then not move back down below the 4th cog!!

The shifter cable is new and all the components,derailleur,shifter and cassette are in excellent condition.

I have no experience of doing these,by the way and may be missing a trick or two.

Any help will be most gratefully received!


Top
 Profile  
 
 Post subject: Re:
PostPosted: Sat Aug 18, 2018 9:40 am 
Gold Trader
Gold Trader
User avatar

Joined: Mon Jan 15, 2007 11:40 am
Posts: 3494
Sounds like either the mech, dropout, or both are not quite straight. The mech being a lower end model, if it's already used then the pivots might have play in them too, which doesn't help either


Top
 Profile  
 
 Post subject: Re: Re:
PostPosted: Sat Aug 18, 2018 3:28 pm 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
foz wrote:
Sounds like either the mech, dropout, or both are not quite straight. The mech being a lower end model, if it's already used then the pivots might have play in them too, which doesn't help either



I just checked and everything looks perfectly straight and in line from the rear.The mech has had virtually no use and all the pivot points are snug.

It's tantalisingly close to shifting correctly through the whole cassette now as though all it needs is the right tweak!


Top
 Profile  
 
PostPosted: Sat Aug 18, 2018 4:19 pm 
Old School Grand Master

Joined: Mon Feb 11, 2008 9:42 am
Posts: 3117
You need to actually measure a rear mech hanger, i have a good eye and mine appeared straight. 3 degrees out.......... in two planes.

Any LBS will have the tool. Theres probably a retrobiker near you with one as well.
Or you can thread a normal rear wheel into the hanger and check that the wheels are parallel to each other in both planes.


Top
 Profile  
 
PostPosted: Sat Aug 18, 2018 4:25 pm 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
mattr wrote:
You need to actually measure a rear mech hanger, i have a good eye and mine appeared straight. 3 degrees out.......... in two planes.

Any LBS will have the tool. Theres probably a retrobiker near you with one as well.
Or you can thread a normal rear wheel into the hanger and check that the wheels are parallel to each other in both planes.



Thanks for the tip,before I take it to my LBS I'll try a rear wheel the way you describe.


Top
 Profile  
 
PostPosted: Wed Sep 05, 2018 9:53 am 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
I had the hanger etc checked at my LBS the guy can't figure out why the mech won't index,(it's only out by a fraction from the 4th cog up).All parts appear to be in good order,his best guess is there is some slight wear in the shifter as it doesn't appear to be pulling quite enough cable as the mech climbs the casette.

Further suggestions welcome.....


Top
 Profile  
 
PostPosted: Wed Sep 05, 2018 11:44 am 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
Posts: 2387
Location: Sheffield, top city
Markone wrote:
it doesn't appear to be pulling quite enough cable as the mech climbs the casette.

Further suggestions welcome.....
just checking .... they're not 8 speed levers are they, which would give the above symptom?


Top
 Profile  
 
PostPosted: Wed Sep 05, 2018 12:05 pm 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
pigman wrote:
Markone wrote:
it doesn't appear to be pulling quite enough cable as the mech climbs the casette.

Further suggestions welcome.....
just checking .... they're not 8 speed levers are they, which would give the above symptom?



No,definitely 7 speed,only six clicks....


Top
 Profile  
 
 Post subject: Re:
PostPosted: Wed Sep 05, 2018 5:13 pm 
Retro Guru

Joined: Wed Dec 10, 2008 9:19 am
Posts: 2387
Location: Sheffield, top city
fair enough!

just another check ... is it a proper 7 speed cassette? for example on 1 bike I have, it has a 8/9/10 speed freehub. On it I have a 6 speed uniglide cassette and I have replaced the bottom screw on cog with a further 2 six-speed width cogs. So it looks like 7 speed, but has 5.5mm spacing instead of the normal 5mm spacing. It's very tolerant to not needing fine tuning with friction levers. Again, this would manifest itself in the symptom you describe.


Top
 Profile  
 
PostPosted: Wed Sep 05, 2018 5:30 pm 
Devout Dirtbag

Joined: Wed Jul 20, 2016 10:27 am
Posts: 144
Yes,it's a complete and proper uniglide 12-21 7 speed cassette!It's all a bit baffling really,unfortunately I don't have another 7 speed shifter to try.........yet!lol

Of,course using the shifter in friction mode it shifts great!


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 15 posts ]  Go to page 1, 2  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: toby1974 and 13 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

About Us

Follow Retrobike

Other cool stuff

All content © 2005-2015 Retrobike unless otherwise stated.
Cookies Policy.
bikedeals - the best bike deals in one place
FatCOGS - Fat Chance Owner's Group

Powered by phpBB® Forum Software © phpBB Group