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Here’s the Punchline: Sometimes You Just Need a New Stinkin’ Derailleur

The shifting on my rain bike has been something of a mess for quite a while. It wasn’t horrible, it just wasn’t perfect. It was… really, really close, but really, really close is only good in horse shoes and hand grenades.

If, and I do mean “if”, I got it dialed in so the bike shifted up and down the cassette crisply, one gear would catch and skip… usually in the small cogs. Again, it wasn’t terrible, it just… lacked. Now, this gets fun. I found if I mixed the seven smallest cogs of a Shimano cassette with the three big cogs from a SRAM PG-1070, 98% of perfection was achievable. I know. I’m a bit of a geek that way. The problem with that flawless shifting was that the chain would make the faintest skipping noise even though the shifting was right on. This drove me a little nuts (and likely those who drafted behind me, though my wife said she never really noticed).

This was in stark contrast to my Venge, which is perfect. And that perfection magnified the lacking of the Trek to a point it diminished from my wanting to ride it (thus, I took my Venge on our northerly road trip a couple of weeks ago).

So, whilst perusing the interwebz the other day, I happened upon a glorious find… a brand new Shimano 105 5701 GS rear derailleur. It was magnificent and only $45. I ordered that and a set of pulley wheels for my wife’s bike.

Well, Thursday night after I got home from the office, I changed that sucker out and took her for a ride. And… 98% became 99%.

Halfway through my ride, I knew exactly what the problem was… the chain was barely slipping on the 4th biggest cog… the first on the transition from the SRAM to the Shimano cogs.

When I got home, I dug out an old SRAM PG-1070 that I used on the Venge for less than a season. It’s a very nice, $86 cassette, but I didn’t like it on the Venge. An Ultegra was better for… well, I just wanted to keep the Ultegra line on the Venge. I slapped that almost new cassette on the Trek, shifted a few times… and zero skipping and no annoying noises.

It is beautiful. And with that out of the way, I’d been toiling away, trying to find the drag in the system that was messing up my shifting for way too long. I’d replace a cable housing here and an end-cap there. I thought it could have been a housing length issue, maybe… I was just about to take it to the shop when I found that derailleur on Jenson. Sometimes you just need a new stinkin’ derailleur.

Of course, choosing between bikes will be that much more difficult, now. But that’s a good kind of difficult.

PS. By the way, I set the thing up myself, from Hi and Lo limit screws to the B screw… and got it exactly right within ten minutes. That I didn’t screw it up had me pretty ecstatic.

Perfect Shifting on a Shimano 10 Speed Drivetrain Requires Perfect Cable Housings, Ferrules, and Fresh Cables

I’ve written before, in a disjointed “update” fashion, about my adventures with Shimano’s 10 speed shifting problems but after yesterday’s adventures, it’s time for a full post. Necessity is the mother of fixing a road bike’s drivetrain is how the saying goes, methinks.

First, Shimano’s 10 speed drivetrains (105, Ultegra, Dura Ace) are notorious for poor shifting quality if there’s any drag in the cable system. And by “any”, I mean any. No drag? Fantastic. Drag? Read on… I won’t be dealing with the normal culprits in this post, things such as dirt, grime, wear, excessive lube, installing the cable improperly on the pinch-bolt of the derailleur, frayed cables, sweat and sport drink-caked cable guide, etc. This post is for a more nefarious issue.

If you’ve got drag in the cable system, here’s what it will present as, in two different scenarios – each on a different bike, with a different component line (Ultegra and 105).

With the first, you can get the shifting dialed in, but it’s hard. One quarter-turn either way and it’ll shift good going up the cassette or down the cassette, but not both. You’ll get a hesitation on one or more gears while others will work just fine. If, however, you get the barrel adjuster dialed in just right, it’ll shift perfectly. It’s liable drive you up a wall, too, because the cause can be tough to track down – it was for me.

In the second scenario, and worse, you’ll get clicking gears, almost like you’re half-geared, going up or down the cassette, but not both. Motherf****er, I’m getting worked up just thinking about it. It gets worse; it’ll happen on specific gears only, upper, lower or middle of the cassette depending on which way you’re adjuster is misdialed. Oh, it gets still worse. You can get it dialed in just right in the big ring, but it’ll click in a couple of gears when you shift to the little ring. We’re going to deal with this scenario first, because it’ll drive a person mad. It did me.

The clicking problem presented itself on my Specialized Venge. Shimano Ultegra 10 speed. I switched housings, cables, almost everything and couldn’t find the damned gremlin. Then I gave the mechanic at the shop a crack at it. He made it better by installing new cables all the way back, but I still had to have it dialed in just right… and I still had the big ring/baby ring problem, though as little time as I spend in the baby ring, it was livable, at least. Still, it bugged me to no end knowing there was something off.

In the end, I got lucky finding the problem. The mechanic at the shop ran the rear derailleur housing exiting the handlebar and entering the down tube about a centimeter too long. It drove me nuts seeing it not symmetrical with the other side. I decided to tinker with it one Saturday to get that cable length corrected. When putting it back together, the ferrule (end cap) was a coated plastic… I didn’t like it and swapped it out for a metal end cap before putting everything back together. After HOURS of monkeying around with it, shifting perfection was achieved at long last. It was that one little freakin’ plastic ferrule that gummed up my shifting so bad, a pro couldn’t figure it out.

Second up is the hesitation in the shifting on my Trek, Shimano 105 ten speed drivetrain. Now this was a little trickier to pin down for one fun reason. The whole bike, from the ground up, is new except for the frame, fork and chain ring bolts. I chose the cable housing lengths myself, based on a guess. I threaded the housings through the handlebar ports. I put it all together myself, brakes, shifters, housings, end caps… all of it.

So let’s just say there was a lot I could have messed up and leave it at that.

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I checked everything and was simply flummoxed. No plastic ferrule, no bad housing, no drag in the system… in fact, I went so far as to leave the rear loop alone because if it worked on the old 9 speed system, why mess with it, right?

Guess what I found out Sunday night? Yep, it was the rear loop that worked perfectly on the original 9 speed system. It was the only thing I hadn’t changed and before I messed around with changing new stuff, because I’d finally had enough, I just wanted to make absolutely sure. I cut a new length of shifter housing (there’s a difference between brake and shifter housing, by the way) and put two brand spankin’ new end caps on each end, threaded it on, connected the cable to the derailleur, dialed it in with the barrel adjuster… et voilà. Doh! Perfect.

The problem inherent in the ten speed system was corrected in the eleven speed drivetrain. The fix for a ten speed system can seem complex, but with a little sticktoitiveness it can be dealt with. The tough part is figuring out where the drag is in the system.

If, by some unlucky stroke, you run into this on your bike, the best advice I can give is run the whole cable system new back to the derailleur. New housings, new cable, new end caps (and be sure to use metal caps)… no frayed ends on the shift cables, too. The problem is drag on the cable, even the slightest little bit will throw the system off, so I wouldn’t use a heavy lube on the cable, either. In fact, if you’ve got decent housing, I’d stay away from lube altogether. Modern shift cable housing doesn’t require it, though check the manufacturers instructions for yours, just to make sure.

This post assumes, of course, that all other issues are dealt with, like a gummed up cable guide (under the bottom bracket shell), the cable is on the proper side of the pinch bolt, the cables aren’t frayed or rusted, the housings aren’t gummed up, etc. etc. etc.

The Pursuit of Road Bike Perfection; Making Your Road Bike Shift Better and Diagnosing Problems That Can Cause Poor Shifting in Shimano 10 Speed Drivetrains (Tiagra, 105, Ultegra and Dura Ace)

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Most people wouldn’t notice that cable housing sticking out a little farther than the other side… I’m not most people.  It drove me nuts!

I wrote yesterday about fixing the rear derailleur shift cable housing that was installed a bit long at the shop because the mechanic was trying to get my system to shift better than I was able to eek out of it when I upgraded the drivetrain from 105 to Ultegra (both 10 speed).

Now, Shimano’s 10 speed system is notorious for running into shifting problems because the rear derailleur’s spring was a little weak.  Searching the internet for help is a struggle in and of itself because there’s a lot out there, but not much is specific.  I can tell you, based on my experience, they fixed the problem with the 11 speed drivetrain – my wife’s 11 speed operates perfectly – and she’s a little harder on her rig than I am on mine, especially on my Specialized Venge.  That bike has only seen two or three raindrops since I bought it new in ’13 (a bit of an under exaggeration, but not by much – I have a very nice rain bike).

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I ran into trouble when I bought a used Ultegra 10 speed drivetrain from a friend.  I had a tough time getting the shifting dialed in right after the upgrade… and I had a harder time trying to figure out what went wrong.  After an exhaustive search on the internet, I gave up and took it to the shop.

The shifting was much improved after the shop mechanic had his way with it, but it still wasn’t perfect.  He didn’t like it either, but it was the best he could do.  We blamed it on the idea that the shifters were overused rather than just “used”.  The derailleur had to be dialed in within 1/32 of a turn for the rear derailleur to operate smoothly and (more important) quietly.  Specifically, one of the middle gears would click either going up or coming down the cassette (but not both) if the indexing of the rear derailleur was a little off. It shouldn’t be that difficult to get it dialed in and everything I found on the interwebz said the culprit was drag in cable.  I just couldn’t find it.

Fortunately, on more of a vain note, I hated that the rear shift housing stuck out too far from the frame – it didn’t match the cable on the other side.  I left it that way for a full season because I figured it would be better handled over the winter when I had the time to take it to the shop if I messed something up… better to ride the bike when I can ride it, right?

So, after thinking the process through, I went to work as soon as I had some time after the snow flew.

First things first, I wanted to shorten that cable housing, because doing that gets the shift cable out of the way to really look at how the cable could be getting hung up elsewhere.  For that, I had to pull the rear derailleur cable out far enough that it was inside the housing that leads from the down tube to the handlebar and shift lever so I could snip the housing but not the cable.  This is a simple process for externally routed cables.  For internal cables, it’s a bit more of a big deal.  The problem is running the cable back through the frame.  Mechanics use magnets to feed the cable through the frame – this works especially well with the bike right side up on a stand, as gravity helps, but you can run into problems with some bikes because running new cables requires removing the crank.  To avoid issues, I like using cable liner.  With cable liner, I can run new cable in exactly the same place the old one was when I pulled it – and cable liner, for this purpose, is reusable and cheap.  (Jagwire 1.8mm x 30 meters runs about $11 on Amazon – the 1.8 is a little thicker than others but a shifter cable slides through it more smoothly than the thinner options… the only problem is fitting it into some ferrules/end caps).

So, I did this to trim the housing, but if you’re looking for drag in your shifting system, do the same thing, just don’t snip the housing.  Shift the bike all the way to the small cog on the cassette.  Take the aluminum cable cap off with a pair of needle-nose pliers.  Make sure there are no frayed hairs on the cable tip (give the cable end a quick twist to seat a frayed end if needed) and thread in your first piece of cable liner that you cut long enough it’ll stick out of each hole in your chain stay over the shift cable.  Once your liner is through the chain stay, pull the cable until it’s hanging down from the bottom bracket cable guide.  Unbolt the cable guide cap and remove the small piece of cable liner (if you have one).  Then thread on another pre-cut piece of cable liner that’s long enough to stick out the hole at the bottom bracket and where the cable enters your down tube.  Once it’s through, take two pieces of electrical tape and tape both ends so the liner won’t fall out on you.  Pull the cable through the cable liner.  With the cable out, roll your shifter hood up from the base to expose the hole for the shift cable.  Push on the cable at the housing end until the head of the cable pokes out of your shifter.  Then, carefully pull on the cable head at the shifter until the end of the cable is at the tip of the housing.  Pull the cable another 3″ so it’s well inside the cable housing.  This will ensure that the cable is well inside the housing so you won’t cut it when you trim the cable housing (unless you just want to install a new cable – in that case, pull it all the way out).  Clip the housing and make sure the hole is round.  Put a housing end cap on it and check to see you got the length right – better to cut off too little and have to trim some off than cut too much and have to replace the housing all the way back to the shifter lever.  Push the cable back through until the head is tucked in its hole in your shifter.  Reroute your cable back through the liner in the down tube and pull the liner when it’s through.  If it’ll fit in your system, run a new piece of cable liner at the cable guide underneath the bottom bracket shell (4″ to 6″ will do).  I don’t like leaving bare cable at the cable guide in an internally routed system (the liner in the cable guide limits dirt and thus, cable rot).  Thread your cable through the chain stay liner and when the cable is through, pull the liner and set the two pieces aside to set in a tool box for future use.  Finally, put your derailleur cable housing loop back together and adjust your index your derailleur.

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Now, to shifting quality.  In my case a few of the housing ends were coated plastic and when I put everything back together, I noticed the ends weren’t playing well with the barrel adjuster and I didn’t like how the cable slid through the plastic ferrules (end caps) – it just felt like there was a little drag on the cable when I pulled it through the housings.  Drag is bad when you’re talking about a Shimano 10 speed drivetrain because the derailleur spring is too weak.  Any drag, and I mean any, in the system and the rear derailleur won’t work quite right.  I switched the plastic end caps out for metal one’s and put everything back together.  That solved my drag problems in the shifting system.  The shifting went from acceptable to excellent, just like that.  It also survived a double check two nights ago, and a triple check last night.  I can’t believe how smoothly the drivetrain is operating… I’m a little giddy to ride it.  It’s the cat’s pajamas once again.  The problem wasn’t the used shift levers, it was a little bit of drag in the system from something that shouldn’t have been a problem.  Once that was remedied, et voilà

These issues of cable drag in the shifting system can be exceedingly difficult to find and diagnose.  This one was for me.  The shifting quality was excellent on the original 105 10 speed system but over time, the original plastic housing caps ended up gumming up the cable operation.  I had myself stuck in a box with this before, but some elapsed time and forethought, and small problems were not only simple to diagnose, they were easy to fix.

In the end, the shift quality is all about drag in the system.  The less drag, the better the bike will shift.  And sometimes the problem can be as small as a little ferrule at the end of a cable housing that’s gumming the system up – even a cap that worked before a cable change.  A poor cable housing cut can be a problem, too.  Dirty housings, too much or the wrong lube in the housings, old shift levers, dirt or grime in the shift levers, dirt in the derailleur itself… all can contribute to drag in the system and poor shift quality.

When you can’t figure out what the hell is going on, let me recommend reworking the housing system from the shift lever to the back of the bike.  Serfas complete shift cable system that works well and is cost-effective.  It comes with everything you’ll need to change your old cables and housings and it comes with metal ferrules (or end caps).  If you want to go a little next level, Jagwire is fantastic and their pro kit will be a great upgrade for all but the highest-end steed.  Better still, if you want a little more flash, go for the Jagwire Road Elite Link Kit.  Of course, if you just want to stick with Shimano, they make a couple of different grades of cables and housing kits.  The standard and Dura Ace kits.  I have it on authority the Dura Ace kit is supreme, though I’ve never used it (I have the Serfas on my Trek 5200 and a hodgepodge of Jagwire on the Venge).

Finally, for cutting cables and housings alike, I like Park Tool’s cable and housing cutter.  It’s an expensive tool, but worth every penny when you get a crisp, clean cut.  Watch the brake cable housings, though.  They don’t cut as well because of their design and you have to round out the hole before firing a cable through.

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