Bicycle Mechanics - Shimano Dual Control Lever - problem shifting

I have 9 speed Shimano dual control levers on a Trek road bike. The rear shifter has developed a problem where it won't shift using the small lever (to shift to a higher gear/smaller cog) because it pulls the large lever along and the whole mechanism "sticks." If I let go of the bar, physically hold the large lever still, and then push the small lever, it works fine. There isn't much "user-serviceable" stuff I can see inside the levers. Any suggestions before I haul the bike to the shop? Thanks, Eric Goldin

Eric, I'm not sure I follow your explaination, so let's see what the other guys have to tell you.

As a general rule, if your shifter is sticking, check the cables to make sure they are clean and moving freely in the housing. This is the first thing to check.

Next, as an easy test/fix, put your derailure into the highest gear and then give it a shot of spray silicon. Then, put it into the lowest gear and give it another shot of silicon spray. Work the derailure back and forth a couple of times and see if there is any improvement.

Be sure not to get any of the silicon spray on your rims or on your brake pads, or your brakes won't work.

Anybody else have anything more scientific for Eric to try?

What Eric ment was the Dual Control Levers stick to each other... Like the one in the pict below.. I don't think it is cables. Did you drop your bike on the handle? does it look warped? Maybe you have dirt or something stuck between teh 2 leavers...

http://www.shimanocycling.com/product_images/ST/components/ST-5500-CA.jpg

A

Yep. Looks like an STI lever to me.

Eric,
I had a slightly similar problem with my right (rear) 105 STI shifter. It seemed hard to shift to smaller cogs (small lever) and the levers seemed to want to move together. Shortly thereafter a tiny screw fell out. Apparently the difficulty was being caused by the loose screw. You have to push the big lever way in toward the stem and you will be able to see a tiny screw that holds the small lever to the large lever and serves as a pivot point. See if that screw is loose.
Regards,
Raymond

Eric,
Be sure to let us know what the final outcome is so we can all learn.
Thanks,
Raymond

You guys are correct about STI levers. I did check the screw and it isn't loose; I tried changing the screw tightness to see if it affected the relative "tension" between the two levers and it didn't seem to make any difference. But I'll look closer when I have more time and a better setup (bike's at work this week). Thanks. Any other thoughts will be appreciated and checked out. I'll let you'all know if the shop is the last and successful resort. Eric

Somehting like this is best looked at by a person.

It may be a warranty issue depending of the looks of the lever (i mean not crashed) and the age of the lever.

Here's the scoop. The shop guys say this is a problem with those 9-speed STI levers. The gruppo is slightly less than 2 years old so it's still under warranty. Good news - they'll send the parts to Shimano and I should get new shifters that will not have the problem. Bad news - bike's in the shop for 2-3 weeks while all this takes place. Kinda surprised I didn't see anything about this "common" problem on this forum, nor in any of three others I checked. Oh well. At least I can say that the shop folks (Supergo) were very considerate and are taking my side that it's a defect in the design, to be replaced by Shimano under warranty. Option for me to think about, is to upgrade to DuraAce when the shifters are returned. Thanks to all. I'll dust off the mountain bike now.... Eric

Originally posted by Eric Goldin
At least I can say that the shop folks (Supergo) were very considerate and are taking my side that it's a defect in the design, to be replaced by Shimano under warranty.

The Supergo I shop at in Santa Monica is a 25 mile drive for me but well worth it in my opinion.

The closest good LBS for me is Bicycle John's which is still 10 miles away. Their prices are higher than Supergo but they do have excellent customer service. Bought a 1" stem today from them then realized I needed a 1.125. Took the stem back and he didn't have the Ritchey in a 1.125. Swapped me a Cinnelli straight across that cost $30.00 more (weighed more too) and told me to try it out. If I'm happy with the size he'll order me something nicer when I bring it back. Very cool...:thumbup:

Too bad you gotta wait to get your bike back. But hey... You've still got your mountain bike :) Clean that puppy up and remember how much fun they are!

I was happy to find this thread, as my Ultegra shifter is doing the same thing. It took me a while to realise that I also had to reach around and stabilize the big lever while clicking the small one, then it works flawlessly. However this is a major hassle and distraction when trying to concentrate and stay aero.

I looked inside and the screw was actually gone, so I went to the hardware store and bought a rough approximation.

Now the levers feel "stable", not mushy like before , but it still won't shift into higher gears and i still need to hold the two levers in order to shift.

I have even learned a way to do this with two fingers while still holding the hoods.

Interested to see how the warranty thing goes as this bike is one and a half years, but my bike shop is in another country.

But, what IS the actual defect?

Hi. Have read the thread. I have a 2007 Scott Speedster fitted with these Shimano dual control levers. The right shifter works fine, but the left i.e. front derailleur suddenly stopped working and would not change down to the smaller chain ring. Took it back to the shop where they replaced the whole unit FOC, no hassle. Worked fine for two rides and then stopped again. The bigger (brake) level does nothing when you push it to the right, as if there is no cable attached to it - no resistance at all. Then bizzarly, the next day, it started working again. The shop say I'm pushing it too hard but I find it very strange that a mechanical device can do this. Does anyone have any tips or experience with this problem? Is there a way to fix it if it happens suddenly? Thanks - a very new road biker.

A cheap and easy way to "overhaul" STI shifters is to shoot WD40 into the shifting mechanism. Sometimes this makes impressive improvements to shifting performance. Using the smaller shift lever releases the cable so that the derailleur spring can move the derailleur. Either the factory grease hardens and/or dirt gets in into the shifters and causes excess friction. The WD40 does a good job of loosening the grease and removing dirt. Replacing the shift cables and cable housing can also make significant improvements. Any excess friction along the path of the cables can impair shifting performance. When replacing the cables always replace the housings.

Al

+1 on the WD40. i had a friend with shifting trouble. shop told her she'd have to replace the shifters (older 8sp brifters) I couldn't really find anything wrong except age and a bit of crud, so i sprayed WD40 untill it ran out down the handlebars. I'm not generally a WD40 fan, because it's mostly solvent with just a little light oil under pressure, but that's exactly what's needed here.