Upgrade thumb shifter and cable, but not housing
 

Hi,

Recently got a new Giant Escape Disk3 and want to upgrade the Microshift thumb shifters that can on it. I did so and would like to replace the shifters (Microshift) without replacing the cable housing. The cable housing on this bike runs down and through (internal) some of the bike tubing, thus my preference to just run the cable. As an older senior citizen (not afraid of tackling this kinda stuff), I thought you all might help with the best approach.

1.) remove old shifter, disconnect cable at the derailleur and pull old cable and shifter out. Then thread new cable through existing cable housing back to derailleurs, connect and mount shifter. Go riding...

OR

2.) loosen cables and shifter, but open old shifter and remove cable at the shifter, remove shifter, then open new shifter and install cable end in place and mount shifter...but in this case NOT remove cable from housing..

My fear is that if I pull cables out of housing, I may not be able to snake the new cable back through existing cable housing, in which case, I would have to redo all the housing and since it goes internal, that may be outta my league...so to speak

So...experts...what approach would you recommend...?? # 1 or # 2

thanks

JDR

Dirt in the housing is usually the reason for crappy shifting, thus I would change the housing same time you change cables.

Do a YT search for feeding housing into internal frames.

Try this. Estimate the length of cable that's inside the frame and cut a fresh piece of housing to that length, plus enough to stick out at both ends. If there there's a a ferrule or cable stop at the derailleur end of the cable, remove them. If there's a cable stop at the head tube, detach it from the frame. Now slip the new housing over the derailleur end of the old cable and use it to gingerly push the old housing and cable out through the head tube end. When you get housing showing at both ends, remove the old cable, insert the new cable, remove the housing and trim, replace the ferrules, cable stops, and the new housing, and presto!

Also, if you do lose a cable end inside a frame tube, a J-bend spoke works best for fishing it out.

Thx for ideas guys...I'll give it a shot.
JD

If you are replacing cables always replace housing unless for some reason it is a brand new housing and you frayed the cable when installing it or some such error.

This. Often when changing only the inner cable, the groove the old cable has worn in the housing (a cause of much of the new cable "stretch") does not fit the new cable well, which causes excess friction. It is my experience that it is well worth the additional work involved. I use die-drawn stainless inner wire with lined housing; coated inners are problematic and unnecessary.

Thx all for your tips. I replaced the shifter cable assembly and snaked it down thru the existing housing, after inspecting it. As mentioned in my original post, my bike is only about 1 month old, so the condition of the cable housing was fine, and since I ride on dry pavement, mud and dirt was not a concern. I will take your tips in stride for future maintenance in this area.
Be Well

JD