Bicycle Mechanics - Replacing Shifters/ Brake Levers.. 1st Time

I am getting ready to upgrade my shifter/brake levers. I got a set of Shimano Alivio ST MC20's. I presently have a set of the junk EF29's

I think i have the procedure figured out by researching here and ParkTools. I still have a couple questions however.

1. Can i reuse my existing cables? They are in good shape but i think i would have to cut off the crimp on ends to pass through housings.

2. I think the shifters have to be set in the most relaxed position to install the wire. In the case of my 8 speed, this would be on the #1 (smallest front chain ring) and the #8 (smallest rear sprocket), correct?

3. Does it matter what index position the shifters are in when i attach the respective cables to the clamps at the deraillers? (somehow i think this is a dumb question?) :D

Sorry for the newbie questions. I just like to go into a job with the most info available. I suppose much of this will become self evident once i start.

You can reuse the cables provided the cable routing for the new shifters isnt longer. Just give them a cleaning before you install and lubricate by putting some spray silicone down the housings. Dont cut the ends off the cables but pull them off with a pair of pliers. Get some newcrimp on end covers from your LBS - they only cost a few cents.

The index position and mechanism should be in the position with least tension (small ring small cog). That is #1 at the front, and #8 at the back.

You will probably get easier curves in the cable run if you run them from the handlebars and around the far side of the head tube to the braze-on fitting at the top of the downtube, then cross the cables where they run down the downtube to the bottom bracket. If you do this it may affect your ability to use the existing cables.

1. I'd advise using brand new cables. In fact, if it was my bike, I'd replace the cable housing too. Fresh cables and housing will "crispen up" your shifting. It'll also make the replacement process faster and easier. I'm betting your old ones have a stray wire or two. If so, threading those used cables through the housing etc. will be a pain. Cables are cheap. Incidentally, one of the best bicycle tooling investemts that you can make is for a decent pair of cable cutters. I much prefer Shimano cable cutters to Park. Some guys use a Dremel with a cut off wheel. If you try to use ordinary diagonal cutters, the cables will usually frey.

2. You're absolutely correct.

3. Right again. With the shifter and the derailleur both in the smallest sprocket position, pull your cable taut and anchor it to the derailleur. You'll have to fine tune the cable tension with your barrel adjuster, but if you do it right, it shouldn't take very much additional fiddling.

1. I'd advise using brand new cables. In fact, if it was my bike, I'd replace the cable housing too. Fresh cables and housing will "crispen up" your shifting. It'll also make the replacement process faster and easier. I'm betting your old ones have a stray wire or two. If so, threading those used cables through the housing etc. will be a pain. Cables are cheap. Incidentally, one of the best bicycle tooling investemts that you can make is for a decent pair of cable cutters. I much prefer Shimano cable cutters to Park. Some guys use a Dremel with a cut off wheel. If you try to use ordinary diagonal cutters, the cables will usually frey.

2. You're absolutely correct.

3. Right again. With the shifter and the derailleur both in the smallest sprocket position, pull your cable taut and anchor it to the derailleur. You'll have to fine tune the cable tension with your barrel adjuster, but if you do it right, it shouldn't take very much additional fiddling.



Thanks for the advice. I will replace the cables at least. The housing i will inspect and possibly replace. (never done it before either) I just bought a new pair of Park cutters. Hope they work ok. BTW, my bike is exactly one year old with around 3000 miles on it.

I wouldn't bother with housing at 1yr/3k miles. I know everyone is going to say this is wrong, whatever, I usually get 2yrs, and could get more if I wanted to, out of my housings. When I replace the cables I have a can of aerosol Teflon lubricant with one of those red "straws" for a nozzle. It fits perfectly in the end of 5mm housing. You can just blast all the gunk out of there and get a nice fresh coat of lube in the housings at the same time. I've made some REALLY bad housings work really well for people who don't have enough money this way. You will see the lube come out rust/brown at first in extreme cases and when its good it will look clear or lube colored.