Amateur Ireland

My left shifter will move the FD from the small Chain Ring to the large Chain Ring with one movement of the shifter. When I move from the large CR back down to the small CR then two movements of the shifter are required. Any ideas how I fix this so one movement fo the shifter works?

linux_author

buy a double left-hand 105 brifter?

Al1943

Does not exist, 105's are all double/triple.

JTGraphics

The shifter has two throw distances a short one and a longer one the short throw will push half way for trim another short push will change sprockets, one long throw will take it directly to the next gear.
If you don't have the trims you need to fine tune the FD to get them.

Amateur Ireland

So how exactly do I trim the movement for long and short shifts.
The shifter will move the FD in one full movement from large CR to small CR but it kinda grinds and is not smooth. When I double shift it does not grind. It clicks easily twice and just shifts nicely.
Any ideas?

jays35

I just had my left brifter replaced, warranty work, and the mechanic said it was a double shifter replacing the double/triple.

Al1943

In Shimano 10-speed groups Ultegra and Dura-Ace have double specific shifters, the rest are double/triple compatible. Take a look at the Shimano web site.

Daytrip

Not true. I have a 105 Double. Won't do triple, though Triple 105 shifters will do double if you set them up right.

Al1943

Well, Shimano doesn't agree with you: https://bike.shimano.com/publish/cont...e-st_road.html

iareConfusE

Shimano 105 double shifters will only work for doubles, and their 105 triple will work for both. They probably just got lazy and didn't feel like editing their website. Theres no way the double shifter can work for a triple if it isn't indexed to do so.

iareConfusE

Do you mean from small CR to large CR with one movement, although kinda "grindey"? The grinding sound is somewhat normal, as long as it doesn't sound like you're actually grinding anything down. All you're hearing the the chain rubbing against the FD and trying to make its way up to the larger CR, but having a little trouble catching onto the ramps.

Amateur Ireland

Hi Again,
Nope. The shifter is really fast and smooth when moving from small CR to large...No problem at all. When I am moving from the large CR to the small CR the shifter itself will click easily twice from short trim first and then long movement no problem. When I complete one long movement to go direct to the small CR, the shifter seems to override the trim click and kinda grind past it...to the long movement click. Maybe its fine and I am being totally paranoid. The physical movement is all fine. Its just the shifter sound is not smooth when executing a long shift from large CR to small. Maybe the nature of the 105 Left Shifter.


Do you mean from small CR to large CR with one movement, although kinda "grindey"? The grinding sound is somewhat normal, as long as it doesn't sound like you're actually grinding anything down. All you're hearing the the chain rubbing against the FD and trying to make its way up to the larger CR, but having a little trouble catching onto the ramps.

njkayaker

The "harder" shift is from smaller to larger, especially if there is a large tooth difference. It looks like you have a double crank. It's not clear whether you have a double or triple derailer.

Do you have a "half step" (trim) click in the brifter?

It looks like, maybe, you are using two full clicks to get it from the larger to smaller ring. That would imply that the derailer is for a triple. It also looks like the indexing or the cable tension is off on the derailer, making it not align properly over the chain ring. The grinding implies that there is an alignment problem too.

It's possible that a misalignment happens to work for the upshift but not the downshift.

Al1943

Maybe Shimano has added a new 105 double shifter. They've always been double/triple in the past. Their North American web site and their European web site show that all 105 shifters are double/triple compatible. But now there are three posters claiming 105 double shifters.
????

iareConfusE

Yes, Shimano has a 105 shifter that is specific to only double chainring cranksets. It actually says "Double" on the left shifter.