rear mech

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Tom
Posts: 277
Joined: 23 Jan 2007, 7:54pm

rear mech

Post by Tom »

I have upgraded my Specialized Sirrus comp 2013 model, with a Shimano Deore hollowtech double chainset bottom bracket being 68 mm the two spacers provided, are fitted on the chainside of the bottom bracket, one on the other side.

rear cassette original 11/36 , (still on)
front chainset 40 t/ 28 t Deore Hollowtech)(Fitted) (seems to work fine.)
Original Chainset 48t/ 34 t Sram (Removed)
I am finding that I cannot obtain the last 2 low sprockets no 1& 2 With the Sram 10 speed shifters

disconnecting the cable and trying the mech by hand it will not attain the last sprockets ref above it seems that the mech is at full stretch no way will it go any further
all that is different is the front Deore Chainset and the size of the Chainrings which have less teeth than the Sram original,

Could the problem be due to the Smaller chain rings than the original would I need a longer mech(One fitted is a sram X7/10?

I have run out of Ideas?

Regard's Tom
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cycleruk
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Joined: 17 Jan 2009, 9:30pm
Location: Lancashire

Re: rear mech

Post by cycleruk »

As a test - remove the chain (or unship) and see if the mech' will then span the all the cassette cogs.
I can't think why changing the chainring size would limit the rear mech' movement.
Check the "stop screws" and the "B" screw are correct. Is the mech' being limited because the top jockey wheel is catching the sprockets?
You'll never know if you don't try it.
Tom
Posts: 277
Joined: 23 Jan 2007, 7:54pm

Re: rear mech

Post by Tom »

Done that, it won't line up with the cogs concerned I& 2
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cycleruk
Posts: 6065
Joined: 17 Jan 2009, 9:30pm
Location: Lancashire

Re: rear mech

Post by cycleruk »

Tom wrote:Done that, it won't line up with the cogs concerned I& 2

Have you slackened off the "stop screw"?
You'll never know if you don't try it.
gregoryoftours
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Joined: 22 May 2011, 7:14pm

Re: rear mech

Post by gregoryoftours »

Can you push the mech in with your thumb while turning the pedals so that the chain engages with the biggest sprocket, i.e. eliminating the shifter from the equation? Have you shortened the chain to work better with the smaller chainrings? Possibly if the chain is too long the top pulley isn't pulled into position and is fouling the 2 largest sprockets.
Tom
Posts: 277
Joined: 23 Jan 2007, 7:54pm

Re: rear mech

Post by Tom »

Have taken the stop screw out and disconnected the cable and taken the cage by hand AS FAR AS POSSIBLE BUT STILL NO GO?
Vorpal
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Re: rear mech

Post by Vorpal »

pictures?
“In some ways, it is easier to be a dissident, for then one is without responsibility.”
― Nelson Mandela, Long Walk to Freedom
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SimonCelsa
Posts: 1232
Joined: 6 Apr 2011, 10:19pm

Re: rear mech

Post by SimonCelsa »

when you have eliminated the impossible, whatever remains, however improbable, must be the truth?

somehow you must have bent the hanger very slightly when changing the chainrings......?

Did the bike fall over, did you have the wheels off & rested it inadvertently on the rear mech, were you a bit hamfisted removing the chain..?

all the best, Simon
Tom
Posts: 277
Joined: 23 Jan 2007, 7:54pm

Re: rear mech

Post by Tom »

Thanks all for your help,

I had difficulty removing the rear mech to return on warranty, I may have damaged the hanger thread, thus replacing the new mech may be slightly out of line would this cause my problem?
Brucey
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Joined: 4 Jan 2012, 6:25pm

Re: rear mech

Post by Brucey »

pictures?
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
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