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i am a noob at bike maintenance. my only experience thus far is replacing disc brake pads, chains, hollowtech 1 bottom bracket, repairing a flat tube. but i am slowly becoming more self-reliant.

my next step is to be able to replace shifter cables... i have no internal routing on my bike, and the cables are only housed where they feed into the rear derailer and the two shifters on the handlebar. cables are exposed along the top tube.

research has indicated that the only tools i would need would be the cable cutter/crimper (CN-10)and cable stretcher (BT-2). these tools would cost up to $100.

youtube vids make this operation appear straight forward and simple. is this the case? how much time would it take a noob to perform this operation? how critical is it to own a bike stand for this?

afterwards, i intend to bring the bike to an LBS to adjust the shifting/derailleurs. i have not taught myself how to adjust shifting yet. seems complicated though.

by the way, happy easter!
 

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Cable stretcher is unnecessary. After installation hold the rear derailleur to prevent it from moving inboard and pull the exposed cable to seat all the ferrules.

Always replace the housing too.

And if you do the adjustments in the right order the it's not that hard.
 

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^^^yep. Cable/housing cutter is all you need. I like to have an awl or pick (small nail, etc) to open the end of the housing after cutting it. If I'm being really fussy, I square up the cut ends of the housing with a grinding wheel.

I've had a cable stretcher and after trying it a few time quit bothering with it.

If the bike currently has good clean routing and housing lengths, just copy them. Over time you might learn or think of more optimized setups that minimize friction or excess housing lengths.

Cutting and stringing the housing/cable is pretty quick and easy. You really don't need a bike stand for this. Setting up and optimizing shifting afterward is where the meat is. If you're doing the cables, you might as well take a shot at getting the shifting working too. This is where a bike work stand would come in handy.
 

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It is as easy as the videos show. Get some plain ol Shimano SP41 housing with end caps and Shimano stainless cable. That, with dedicated cable clamp cutters and some zip ties to re-attach the housings to the frame holders and you’re all set.
 

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Measure the new cable to the exact length that is on the bike now.
Follow same routing, taking notice of how the housing bends in locations of bends. You want a smooth flowy arc, too short of a housing isn't good.

Cable will 'stretch' within a couple rides and a quick couple clicks with the barrel adjuster will get you all set.
Stretching is mostly each of the ferrul ends seating onto the cable end, and into the stays. Some cable stretch as well, with time, but initially the housing will seat with some uses and you'll notice it in the performance.

I think getting the shifting dialed in is more challenging than actually installing cable/housing.
 

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"cable stretcher" is quite a misnomer for that tool, honestly.

First of all, cables don't stretch. What happens is that housings compress, the ferrules bed in, that sort of thing. Other things can happen, too, that you don't want...for example, the wires inside the housing can pierce plastic ferrules and muck up your shifting, the outer sheath of the housing can pull back, exposing those wires and causing them to mush around when there's tension on the cable (also causing your shifting to be mucked up), and such. Almost always with the housing, and very little with the cable. Cables themselves might fray, or corrode, or the coating can rub off. IME, good quality cables and housing actually last awhile.

A better name for that tool, IMO, is a "fourth hand" or cable puller which is what Pedros calls the same tool (and the version I have). Other companies use the same names.

I use the tool because it grabs the cable and helps to get the tension where I need it (and hold it there) so I can tighten the pinch bolt without things moving around on me. You can do the full job without the tool. The tool just makes it a little bit easier to grab the cable when there might be grease residue on some things preventing you from getting a good grip.
 

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Cable will 'stretch' within a couple rides and a quick couple clicks with the barrel adjuster will get you all set.
Stretching is mostly each of the ferrul ends seating onto the cable end, and into the stays. Some cable stretch as well, with time, but initially the housing will seat with some uses and you'll notice it in the performance.

I think getting the shifting dialed in is more challenging than actually installing cable/housing.
The pre-stretch (actually compress) method I mentioned will eliminate the settling in period but it only works with split housing setups like the op's. For full run housing the 4th hand (cable stretcher) is pretty nice, but not necessary.

IME with new, slick cables and housing the dialing in part is actually really easy.
 

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The pre-stretch (actually compress) method I mentioned will eliminate the settling in period but it only works with split housing setups like the op's. For full run housing the 4th hand (cable stretcher) is pretty nice, but not necessary.

IME with new, slick cables and housing the dialing in part is actually really easy.
I've been riding bikes with exclusively full-length housing for a number of years now. I never bother with "pre-stretching" cables anymore and it's not an issue. I also put a little more care into making sure my housing ends are trimmed and filed square so they seat solidly in the ferrules (throw away plastic ferrules and replace with metal ones). Just screw in the barrel adjusters, install the chain, set the derailleur limits, make sure the chain is in the small cog, shift the shifter into the appropriate position, pull the cable through with just the lightest bit of tension, tighten the pinch bolt, and tweak the barrel adjuster to get ideal shifting.

For interrupted housings, jb's method is where it's at (there are more ferrules to seat and more chances for stuff to settle/compress on an interrupted housing setup). I use that method on my road bike, but I don't want interrupted housing anywhere near my mtb. Also, one trick we'd use in the shop would be to shift each derailleur to the highest tension position (big chainring, big cog), which is a no-no for riding (cross-chaining), but we'd let the bike sit that way on the sales floor or in the stock room, and that would also compress the housings, seat the ferrules, and whatnot. This method will work with full length housings AND interrupted housing bikes.
 

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The pre-stretch (actually compress) method I mentioned will eliminate the settling in period but it only works with split housing setups like the op's. For full run housing the 4th hand (cable stretcher) is pretty nice, but not necessary.

IME with new, slick cables and housing the dialing in part is actually really easy.
I didn't read your comment until I had already posted -then realized we has similar suggestions.

Sounds like OP should be pretty dialed in by now though.
 

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Wrap the cable in electrical tape then use whatever to cut the end. The cable won't fray. You don't need a single bike-specific tool to change a cable, but do get some of those crimpy things for the end.
 

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i am a noob at bike maintenance. my only experience thus far is replacing disc brake pads, chains, hollowtech 1 bottom bracket, repairing a flat tube. but i am slowly becoming more self-reliant.

my next step is to be able to replace shifter cables... i have no internal routing on my bike, and the cables are only housed where they feed into the rear derailer and the two shifters on the handlebar. cables are exposed along the top tube.

research has indicated that the only tools i would need would be the cable cutter/crimper (CN-10)and cable stretcher (BT-2). these tools would cost up to $100.

youtube vids make this operation appear straight forward and simple. is this the case? how much time would it take a noob to perform this operation? how critical is it to own a bike stand for this?

afterwards, i intend to bring the bike to an LBS to adjust the shifting/derailleurs. i have not taught myself how to adjust shifting yet. seems complicated though.

by the way, happy easter!
Hey Randum

As a fellow mechanical slow person, shift cables are not hard after you do it once. The thing that threw me off most is when a video doesn't show them cutting the middle of the cable. Can't stand it when people leave important things out of the video or protocol list, like it's 'assumed'. Assume nothing with someone that never did something before.

1. Buy something like Jagwire $15 or Shimano $20 cables with housing.

2. Cut the cable in the middle somewhere with cheap $10 wire cutters, that is the only special tool you need. Loosen cable from rear derailleur. Open the shifter after shifting up to the highest gear. Dunno about SRAM but Shimano shifters will have a round little piece of plastic under the shift numbers that has a plus on it for a phillips screwdriver. You should see the end of the cable, it has a thick ball on the end to prevent it from slipping out of the shifter. That's why you need to cut the cable, much easier to push it out of the shifter w/a cut cable.

3. Remove cable and housing. Keep the housing (should be in 2-3 pieces) for later to measure for the new housing.

4. Line up the 2-3 pieces of old cable housing you have and then carefully cut them to the exact size using the new housing, that usually comes in a longer single loop. Then stick a small pen knife or large paper clip end through the ends of the new housing to widen the ends a bit so the new cable will go in. Attach the housing caps to each end.

5. Starting with the wire and housing closest to the shifter, thread the shift cable back through the shifter, slide on the 1st housing, secure this to outside of bike, the housing should be just a tad longer than the two points it bridges to provide protection. In other words the housing may bend a little as the cable snakes around to the back of the bike. Always better longer housing than shorter. Then slide on the 2nd housing, secure cable, then 3rd housing.

6. Thread end of shift cable through rear derailleur hole. I personally don't like to cut the cable short, as in leave only one inch or so. I like to leave maybe three inches and twist it over back towards the bike so it doesn't stick out a lot. Crimp is optional, it's really no big deal either way.

7. Adjust rear derailleur normally, secure cable, etc.

If I left any important detail out, please add that detail in!
 

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Hey Randum

As a fellow mechanical slow person, shift cables are not hard after you do it once. The thing that threw me off most is when a video doesn't show them cutting the middle of the cable. Can't stand it when people leave important things out of the video or protocol list, like it's 'assumed'. Assume nothing with someone that never did something before.
They probably left that part out because it's completely unnecessary.
 
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