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sam_aye_am
05-20-2015, 08:39 AM
I have an issue that I'm thinking is actually a shifter issue, not cable or derailleur related. Bike is a 2009 or 2010 Trek Portland with Shimano Tiagra STI shifters, 3x9 and I believe Tiagra and 105 FD and RD respectively. Probably have 10k miles on this bike and probably use the FD 4 times on a 30 mile round trip commute. Is it common for an STI shifter through lengthy service to irreparably loose the ability to properly index the shift cable?

Everything worked fine on the commute home last night. This morning, I had a bit of chain rub noise from the FD. Not abnormal. Went to bump the shifter a bit and instead of getting a click and some release in tension w/o changing from big ring to middle ring as it has always done, it shifted. As that wasn't what I wanted, I tried to shift back up and no luck. Shifted all the way down to inner ring and from there on out, couldn't shift up. Pull on the cable and I could get the derailleur to move and actually shift rings. But, try and click away as I might, I could only get a few mm's of movement out of the FD if using the shifter. Never enough to actually shift up a chain ring.

Rode back to the house and put it in the stand. Played with tension as much as I could...standard derailleur adjustment procedures, but it is clear there is either a problem with the cable between the on frame barrel adjuster and the shifter itself, or there is a problem with the shifter. I don't think it is a cable issue as I put new Yokuzuna premium cables and housings on just a few months ago. I didn't have time to investigate further as I was running late for work already.

Left shifter has always been a bit wonky and is similarly wonky on my 2013 Full Ultegra 2x10 road bike and the GF's tiagra equipped road bike. There always seemed to be an extra click or two in the shifters. Like 3 clicks total to go from big chain ring to little chain ring or vice versa. Road bike, though only two rings also sometimes has 2 clicks to get from big to little rings or vice versa. Always figured it was nature of the beast trying to pack so much function into a tight package. As I've always been more MTB oriented and don't have these problems on my mountain bikes, I just lived with it.

I've googled around and found directions for disassembly for older DuraAce right side shifters and a conclusion that they just don't last very long. But I think that is all old information from what looks like just a couple of years after STI came out. But what I've found makes it seem rather common after lots of use and wear or drying out of grease to not be able to get the front shifter to index the cable properly.

Does all of the above make sense? Time to give in and just get a new shifter, or is there a somewhat simple fix?

paulg
05-20-2015, 01:18 PM
A friend had a similar problem with some older STI shifters not releasing the cable or indexing properly and I remembered a fix I'd read about on some bike forums:

Squirt some WD40 in the mechanism and see if it frees up, it worked like a charm for my friends bike.

I'm fairly sure that STI shifters cannot be dismantled without some serious effort and lots of small springs flying around the room!

Good luck.

dkel
05-20-2015, 01:52 PM
I had similar trouble with my STI a few months ago after only having the bike for a few months. I remember trying to tension the cable, and being unable to pull the thing hard enough to get it to start working. Very frustrating. Anyway, the cable was frayed inside the shifter, causing it to flake out. A new cable returned it to full function. I know you just put new cables in recently, but you may check that they haven't frayed. Good luck!

hozn
05-20-2015, 01:53 PM
Yeah, Shimano road shifters are not really serviceable, apparently. I run Sram (that is one of the reasons, having replaced shifter paddle once now). I also hate how vague the Shimano stuff gets as it ages/wears. I often experienced similar "why did it click twice that time!?"-type behavior on my 105 group before I replaced it with Apex. Much happier, love the decisive shifting from SRAM. Try the WD40, thoughts, sounds like that can't hurt!

sam_aye_am
05-20-2015, 07:51 PM
I had similar trouble with my STI a few months ago after only having the bike for a few months. I remember trying to tension the cable, and being unable to pull the thing hard enough to get it to start working. Very frustrating. Anyway, the cable was frayed inside the shifter, causing it to flake out. A new cable returned it to full function. I know you just put new cables in recently, but you may check that they haven't frayed. Good luck!

Didn't see your reply before getting into the garage after work...and after having to push start my motorcycle to get home of all things.

Sure enough, the cables some how frayed and pierced the cable end cap. Apparently binding the shifter up. Ordinarily, I'd assume some hack did this. But that hack was apparently me. :confused: I know I used my park tool housing and cable cutters and properly de-burred the ends. It isn't like this was my first time at cable and housing installation or replacement. Maybe yokozuna (sp?) cables aren't all that. Maybe I need to suck it up and track down the SRAM equivalent to the GORE Ride On cables I'm using on the mountain bikes. Guess I'll keep monitoring.

On the plus side...relatively easy fix and there is nothing wrong with my shifter. No runs to the LBS or desperate orders on line. And I get to commute via bike tomorrow.

hozn
05-20-2015, 08:15 PM
That is a great outcome. I'm having some issues with my Yokozuna cables/housing too on my road bike RD -- just very difficult shifting. I've been assuming that there's corrosion in there, though this bike hasn't spent too much time in the wet. Perhaps it's related to this. I'm gonna switch back to Jagwire stainless cables and Ripcord universal housing for my road & commuter bikes (like my mtb); the Yokozuna stuff is indeed very compressionless, but I think Ripcord will work well enough and I never had any problems with the housing or cables. And it also doesn't cost $70 per set !!!

DismalScientist
05-20-2015, 09:07 PM
Bar end shifters FTW.

dkel
05-20-2015, 10:12 PM
Bar end shifters FTW.

Fixed gear FTW.

mstone
05-21-2015, 06:34 AM
Fixed gear FTW.

Worst. Shifting. Ever.

dkel
05-21-2015, 07:37 AM
Worst. Shifting. Ever.

Never. Needs. Repairs. :D

mstone
05-21-2015, 08:05 AM
Never. Needs. Repairs. :D

Also never gets any better. :P

Terpfan
06-30-2015, 07:54 AM
Following along this same vein, I noticed my left integrated shifting was a little loose. What's the trick to tightening in. I pulled back the tight plastic hood a little but didn't see a place to tighten a screw/bolt, which is what I presume holds it there in place. They're shimano shifters. I'm sure it's fairly obvious and I'm just missing it, but hoping someone smarter can point it out.

hozn
06-30-2015, 08:10 AM
Following along this same vein, I noticed my left integrated shifting was a little loose. What's the trick to tightening in. I pulled back the tight plastic hood a little but didn't see a place to tighten a screw/bolt, which is what I presume holds it there in place. They're shimano shifters. I'm sure it's fairly obvious and I'm just missing it, but hoping someone smarter can point it out.

You probably just need to pull back the rubber further. For my Shimano shifters I just rolled up the rubber hoods from the base of the hood, not the front. You'll see a 5mm hex bolt exposed eventually; that's what you want to tighten.

Terpfan
06-30-2015, 08:30 AM
You probably just need to pull back the rubber further. For my Shimano shifters I just rolled up the rubber hoods from the base of the hood, not the front. You'll see a 5mm hex bolt exposed eventually; that's what you want to tighten.

Awesome, thanks!

Worked perfectly. Took 20 seconds once I rolled hood back far enough