Sram twist shifter on left #2 isnevr in the same place have constantly play with it every time i shift back to second

that's easy the stop bolts left and right are missing, bad, borken
or mangled. (not photos posted. so damage, is "anything"
suzuki sells these special, harndend shoulder bolts.

part ID 36 times 2.
see it here.

http://www.fixkick.com/buy-parts.html#5sp-shift

the upper shell twist clocks down on to those 2 special bolts.
its spring loaded if spring not broken.,
the spring his hidden and captive for ever in the stick.
replace part 27 for clean shifts, (like new car)

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.

You enter that question verbatim into a search engine and it will bring you to the same resources we would point toward.

SRAM.com has many resources, too. This one might work out.

http://www.sram.com/sites/default/files/techdocs/SL_3Comp_MRXComp_Ins_2_03_0.pdf

Maybe the SRAM website would have a manual.

Yup.

http://www.sram.com/sites/default/files/techdocs/SL_3Comp_MRXComp_Ins_2_03_0.pdf

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

If you are running a SRAM or Shimano Cassette, then the spacing will be ever so slightly off. If you want to have precise clean shifting then you need to either replace the cassette body with a Campy one and replace the cassette with campy or get a 10-speed conversion cassette such as those from American Classic. Campy spacing on a shimano/ Sram spline.

The wheels in and of themselves should not make any difference.

Another trick for perfect shifting, make sure that your rear derailleur and shifter match - Campy to campy, Sram to Sram as examples.

The Scale, known as the gear indicator, has no bearing on the function of the shifting. It is a simple device that connects to the derailleur cable and moves with the cable back and forth as you shift. if it is stuck, then it is broken. As long as the indicator does not affect the shifting then it is probably not worth the replacement procedure, which is repalce the shifter assembly.

If you take the bike into your local bike shop, they can process a warranty for you. SRAM is very good about warranty, and if this part is less than 2 years old you have a very good chance at it being a waranty issue. SRAM however does require you to go through a shop to warranty a product.

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.

before you install the cable shift it in the position of small ring ,then insert the cable pull it and tight the screw in the front deraileur(left lever)to it same to the right