How to change the cable of SRAM MRX comp7 ? - SRAM MRX Comp Bicycle 7 Speed Grip Shifter Set

Which brand of shifters are you using? A SRAM derailleur won't work with Shimano shifters and vice-versa.

So - first; if you are using SRAM shifters with the Red derailleur - then changing to Shimano will not solve your issue but only make it worse.

If however you have Shimano shifters - then this is a good solution.
The Red derailleur should not shift that poorly with SRAM shifters. It is not the best - but it's not bad. If I had the bike in a repair stand I would be looking carefully at the following after affirming that the shifting system was indeed all SRAM:

• Derailleur cage height relative to the large chanring - should be a maximum of 2 mm
• Derailleur cage should be aligned as close to parallel to the rings as possible
• Derailleur upper and lower limit screws should be adjusted within spec and in order to allow the derailleur to travel the correct amount for ideal shifting
• Derailleur cable tension should be correct.

Hope this helps... Let me know if you need more.

I think this is what you are looking for.


http://www.sram.com/_media/techdocs/MY08%20SRAM%20Tech%20Manual%20English.pdf

It's SRAM. A simple web search for "sram mrx gripshift manual" led to...

http://bicycletutor.com/grip-shift-cable/

and

http://www.sram.com/_media/techdocs/SL_MRX_Classic_Ins_06_99.PDF

and

http://www.wrower.pl/instrukcje/SRAM/1999-DTM_MTB_E.pdf

So it's not so much stuck as it is springing back uncontrollably. This indicates a failure of the unnamed shifter to stay in its detents.

Determine the make/model and elect to either replace it with an identical one or upgrade to something better. If it's a SRAM MRX, I'd change to a Shimano model.

I recommend you get a real Bicycle Shop involved.

Web search "replace gear shifter" or whatever else you need to know.

One good resource for the inevitable adjustments that will be required.
http://www.parktool.com/blog/repair-help/categories/derailleur-systems

adjust barrel on rear mech clockwise till gear shifts click brake lrver for next gear repeat same as before with barrel. If this fails stat from bottom og cassette but adjust barrel anti-clockwise to obtain gears.

Keeping a derailleur in a given gear is the shifter's job. If the shift lever/mechanism doesn't click and stay where you place it, something is wrong internally. It will need to be replaced if, for example, a SRAM MRX grip slid away and let the guts fall out.

Whatever your particular dilemma, look for a friendly local bicycle shop to see what they can do for you. I replaced the entire MRX shifter set for a friend using an upgraded and better designed Shimano setup for under $25 and my own labor. But then, I'm an old hand at working on bikes.

For DIY:

http://www.parktool.com/blog/repair-help/categories/derailleur-systems

http://www.parktool.com/blog/repair-help/shift-levers-shifters

http://www.parktool.com/blog/repair-help/shift-levers-shifters

or

http://www.sram.com/en/service/avid/view.php?catID=1&subcatID=3

http://www.sram.com/sram/mountain/category/80

or contact them and ask.

http://www.parktool.com/blog/repair-help/shift-levers-shifters

http://www.sram.com/_media/pdf/sram/dealers/XX-Technical-Manual.pdf

Google this... "Sram X.0 cable change" = many videos

As anything that contacts your hands and controls the shifting is a personal preference I would advise you to find a real bike shop and discuss it with them. You can also look at and manipulate other brands and models before committing.

You should be able to push the cable back on its self, as long as the shifter is set in the relaxed position. Then it will be a case of threading the new cable through the shifter housing.