Has anyone had any issues with a weak spring on the cage return. Mine appears not to pull back hard enough. Is this a known issue. Will warranty on a 7 month old bike cover this if it needs replaced?
Is your gear cable working 'freely'?
That shouldn't stop the cage swinging back though. Tge cable moves it in and out. Mine is having issues with the cage not pulling back hard enough meaning my chain stays slack.
It's either taken a bash and isn't straight so is binding at the top, or it's just gummed up with crunge.
I'd flush it with gt85 and work it by hand for a bit
Never had a mech spring on a Shimano mech go weak. Check your inner and outer cables and check the mech moves freely.
Cleaned mech - still having issues blasted it with gt85 and moved cage back and forth repeatedly to attempt to get some life into the spring.
It appears to spring from the 3 till 6 o'clock position fine but after that it looses power.
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Here is a pic to show - when i pressed down on the chain it stayed in its position - when i encouraged the mech cage back to pull tension it did that.
That might be your freehub bearings or pawls gummed up.
Ah so maybe too much friction on the freehub causing meaning the mech doesnt have the strength to turn it backwards.
It feels loose enough though.
I have had this but am struggling to remember the cause.
Have you had the mech/chain off or even loosened on the hanger?
Its a clock spring that holds the tension - one end against the cage and one end against the hanger via a rotating piece between the mech and hanger.
If this piece has slipped so that its stop is no longer against the hanger then you loose your tension.
With the chain off can rotate the cage so that you can put the tension back?
I hope the above Gobbledy-gook is SOME help.
erm you have confused me somewhat..
It does look from the picture as though the cage spring isn't doing what it should be. But then, the whole mech looks a little odd. I was going to say that you could bring it over one evening and I'd take a look, but you would drive right past Steels to get to me. Anyway, the offer's there.
I'll be going up to Thrunton on Thursday morning for some riding and trail maintenance. I could meet you over there if you like? I'm fairly confident that I could give an accurate diagnosis if I had the bike in front of me; although I can't guarantee being able to fix it in a car park with just my multitool!
I think imp999 is referring to the stop that replaced the B tension screw.
Where the mech actually bolts onto the rear mech hanger, at the rear there is a lip that the B tension screw would locate on a non-shadow mech. On the metal plate that goes from the mounting bolt to the torx bolt on the mech, there is a metal protrusion that locates itself behind the B tension lip.If that doesnt make sense, theres pictures on th elink below.
[url= http://techdocs.shimano.com/media/techdocs/content/cycle/SI/SI_5W70A_005/SI_5W70A_005_En_v1_m56577569830655487.pdf ]Installation of rear derailleur[/url]
Shadow derailleurs still have a B-tension screw - it's in section 5 of the instructions you linked.
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Indeed they do, but it doesnt act upon the same point that a non shadow mech does, but that lip can be incorrectly located.
It looks more like something is stopping the cage from fully returning than that the spring is defective. Did you check that the little nub that bigyinn mentions is seated properly against the hanger? The mech does look kind of funky, like it's rotated clockwise from where it should be. When it it start doing this?
EDIT: what is operation like when the gears take up all the tension? Have you changed your chain?
yesterday i noticed it really - ive been looking at getting a medium cage one as it always looked that the bottom of the mech cage was very low - near the edge of the rim.
when there is no chain on it does go futher back up to the 9 o'clock area.
Check your freehub - looks like the freehub isn't allowing backpedalling to happen. The mech isn't really applying much force to pull the chain through, it is just keeping the chain tight
How does the mech feel spring-wise when there's no chain fitted? Does the cassette spin easily?
it looses power when its in the 6 o'clock verticle position back towards 9 o'clock position.
Casette spins backwards fine with no chain on.
Off to LBS to see what the 2011 five is setup like.
I've seen this yesterday and compared to my mech which is new, the spring feels very soft, was also a little play in the pivot compared to mine.
it looses power when its in the 6 o'clock verticle position back towards 9 o'clock position.
Then perhaps it is the cage spring, it's just not easy to imagine how such a thing would happen. Take the bike with you to the shop; it'll be pretty simple for them to determine why/how it's acting up.
pretty simple for them to determine why/how it's acting up
rider error the answer I think.
Took it to breezes and put it next to a 2011 five - massive difference in the power of the mech. Spoke to Orange who said the shop I bought it from need to send it to Maddison - what a clart on.
Tink I will buy a new one then sell the warranty replacement.