Spandex_fairy

These are the short reach version that comes on small bikes (<52cm). My bike recently developed an issue where it doesn't want to shift into the two smallest cogs. The first lbs I took it to attempted to adjust it, but came to the conclusion that the brifter itself is broken. They mentioned its typical and you just never know when it'll happen; my bike has <4k miles and it's 1.5yr old. I took it to lbs #2 for a second opinion and they are able to tune it to shift throughout all gears, but the indexing doesn't seem as accurate as it was before. I took it for a ride and was caught off guard a couple times- I'd shift a gear, not knowing it hadn't occurred, then go to pedal standing and nearly fall over.

Is this a known issue with Shimano brifters? Is it just specific to my model? Should I just have the cables replaced? A new brifter is $215+labor vs [I'm guessing] $30-60 for a new rear cable.

Maelochs

I am clueless .... you have been warned.

I never let not knowing what I am talking about stop me ...

7000 series is good stuff. Bike mechanics are whoever the shop can afford .... shops don't always want to pay the best what they are worth, so they get whoever will do a minimally adequate job for less .... sort of like with cars, where the substandard mechanic will just replace parts until he gets to the one thing he should just have adjusted in the first place.

"If I can't figure it out is must be totally broken." Except the next shop got it to work better .... hmmmmm .....

First off ... replace your own cables. If you are careful you might not even have to unwrap the bars much---i have threaded cables back through the existing housing a number of times .... WD-40 to clean them out inside, and then just gentle care. Or, if you have a desire to pay for the work .... take the time to find a shop you really trust. People who can't fix bikes .... considering how easy it is to fix bikes .....

Here is a word of warning about Shimano shifters .... if they start messing up, REPLACE THE CABLES. I Have been through this. When the cables age and fray, they stretch a little before they snap. This means you cannot tighten them properly to index them properly. They stretch and won't get to the smallest (highest) cogs, so you keep tightening and the cables keep stretching ... until they snap, in which case A.) you can have a nightmare task to pry the cable end out of the brifter (or the lame mechanic will break the brifter trying, and charge you for a new one) or ...

The cable will snap, the ball-end will pop out, and jam itself into the mechanism and break ab bunch of tiny parts which cannot be replaced, so you need a new brifter anyway.

IMMEDIATELY replace the cables. Do not wait. No matter how much the cables and/or the labor costs, it is cheaper than buying and paying for labor to have new new brifter installed ... and you will still have to pay for new cables.

Just my opinion, based on nothing but having lost a brifter this way, and having saved a few others.

Kontact

Echoing Maelochs - did anyone check the cable inside the shifter? They are only good for one season before they come apart, strand by strand.

msu2001la

Replacing the cable and housing would be a good first step in troubleshooting any issue like this. I'd definitely try that before buying a new shifter.

It's possible that your 105 shifter really is broken, but I'm skeptical of the claim that this is "a known issue" or is "typical", especially on a new bike. It sounds to me like you might have a bent rear derailleur or some other issue going on, especially if shop #2 was able to get the shifter working through all gears.

prj71

Oh goodness. Here we go again.

This is simply not true.

genejockey 

Mileage may vary, but short derailleur cable life is a known problem with Shimano STIs, and inability to access the smaller cogs as well as slow, indefinite shifting is a symptom.

Racing Dan

"known issue"?

Nahh, not to my knowledge, but it may be broken just the same. Imo, try replacing the cable and have the mech hanger checked before replacing the brifter. Bike mechanics have been known to invent business for them selves. Its a "known issue" .. ;-)

Spandex_fairy

They did expose the cable around the rear derailleur. They also peeled back the hoods. They couldn't articulate what was broken. They just said it's the brifter and it's common enough. They also exposed the cable at the derailleur. It was a pair of early 20s guys; one was stationed in the mechanic's section, the other a sales floor guy.

I have a sneaking suspicion that these guys want to pump up their sales figures, since the previous week they just sold me on an expensive carbon stem, when I already had one; it just wasn't Bontrager branded and therefore wasn't "safe" to use (according to them the new Emonda steer tube requires their own branded stem for safety reasons, and there was a service advisory submitted by Trek).

I had a feeling it was exactly as described previously: that they arent good mechanics and the easiest thing to do (for them) is to just replace parts. The bike has never been crashed/dropped/bumped, so it's definitely not the derailleur hanger.

msu2001la

Carbon steerer breakages, statement from Trek Bicycle - VeloNews.com

3. Use only the stem brand and model that came with the bike. This one is a little tougher for most racers as we understand the desire to go lighter, lower or longer with their position. But not all stems will work with carbon steerers. In fact, the lighter the stem, the less chance it will be compatible with a carbon steerer. The maker of the carbon steerer can only assure the compatibility of the stem they spec on the bike. This is reality. Therefore, the only safe approach is to stay with the stem brand that shipped with the steerer.

Trek has been proactive in this matter. We notified all of our dealers last fall with a service bulletin warning of the above compatibility and installation issues. These warnings are also covered in our owners manual and on our website. We have also recently notified the Consumer Product Safety Commission of the compatibility conflict with aftermarket stems and carbon steerers and are waiting for their direction on next steps.

Maelochs

Trek .... loses some respect from me, there. CF steerrers? Yeah, nothing new there .... have them on bikes I Built, so no "manufacturer's suggested model" there. Pretty much, assemble everything correctly and don't LarrySellerz the clamp and you are fine.

As for how cables break or what the symptoms are ... when my fifty years of experience tell me something other than what some "expert' says .... fill in the blank.

I cannot say for sure why I have seen the things I saw, but i know what I have seen.

Change those cables. Any mechanic who looked at the cable by the rear derailleur and said the brifter is broken has his head at the wrong end, shall we say?

Spandex_fairy

Thanks for that, msu2001la. I stand corrected, however, I only knew of this issue as it pertained to the one piece RSL bar/stem combo. I didn't know it also applied to the standard parts. It all sounds a bit hooey that Trek advises the use of only their products. It's good to know lbs #1 wasn't lying.

I've decided upon changing the cable out for a new one. I've been told many different stories behind cable quality and it's effect, or lack thereof. I've heard that cables can go years and tens of thousands of miles before being replaced, and I've heard Dura-Ace, or the like, make no difference in durability. Any strong, valid opinions regarding cable quality and it's effect?

Maelochs

I have only strong, invalid opinions.

I bought a box of tn (I thnk ... maybe 12) Shimano cables on sale somewhere many years back. I have also had good luck with cables from Walmart.

Unless there are some special coatings (didn't Ultegra used to come with some outer sheath which tore up and gummed up the system? I know it did on mine) or something, it is just braided steel with metal knobs on the ends. Thanks for the question, I will be interested to see what I don't know. But as far as it goes, I have never seen a brand which worked noticeably better than another.

Kontact

I've worked in bike shops since the introduction of road STI. Yes, the design of all of them damages the first inch of cable. Depending on the amount of riding/shifting you do, they fail in as little as a year.

Many of them fail in a way that permanently jam up the lever mechanism, causing the owner to have to spend hundreds of dollars to replace the entire lever and rebuild the shifting and brake systems attached to it.

Since the cable cost is as little as $3, they should be replaced yearly on bikes that get ridden. If you do that, you might forever avoid breaking a cable at an inconvenient time or spending three figures and waiting a week to replace it.


And that's the simple truth.


Dunno what's going on with the OPs bike. I can think of 5 things that might cause the problem that can be fixed, but I was very good at my job. The cable is just the most obvious one.

Spandex_fairy

are you saying that by changing cables annually, one can avoid significant damage to the brifter? If that's the case, then I will learn how to do it myself. I didnt know that going to cable failure could result in significant damage.

Kontact

Bike shop employees are paid hourly, not on sales numbers.

If you suspect you were lied to, call Trek and have them explain about the stem. I thought the issue was clamping a round stem on a not-round steerer tube. That's never okay.

Spandex_fairy

The steer tube has a rounded outer perimeter. It's the inner tube shaping that isn't.

Kontact

spelger

great, now i will have nightmares for a while.

Spandex_fairy

prj71

Kontact

You can't help some people. You'd think regularly replacing a cheap cable was like donating a liver.

genejockey 

msu2001la

The OP's bike is still shifting, so the cable isn't broken.

Maelochs

I have felt what the OP might be talking about when cables were getting old and near to breaking .... and I know they were getting old and near to breaking because not long after, they broke.

Nowadays, when I feel the same thing, I change the cables. beats changing a brifter.

You guys do whatever seems best to you.

Kontact

Not true. As they break they get longer.