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I am just wondering if it is to be expected for one to have to click the left STI shifter once all the way and then again about halfway in order to move the FD to move the chain to the big chainring. To change down, the smaller lever has to be pressed for two clicks and then one more.
Is this normal or should the change be complete with one movement? If so, is it the limit screws that require adjustment?
04-06-06, 03:17 AM
Typically when you are shifting the chain on the rear cassette, your chain is obviously in a different position or angle, when it is on the small cog as opposed to being on the largest cog, so it may end up rubbing on the front derailleur after a shift. In order to accommodate the varying angles, your front derailleur needs to be able to make minute adjustments. With friction shifters, when you adjust the rear derailleur, if the front ended up rubbing after the shift, then you would just make that minute adjustment. It's really no different with your shifters. The chain angle still changes, hence there may be a need to adjust the front one by clicking it over once. So if your front derailleur is all the way to the left and you want to shift to the larger chainring, you may have to go two or three clicks to get to the big one. Is it normal? Yes. If you didn't have those minute adjustments, it would rub a lot, driving you nuts and wearing out your derailleur unnecessarily.
In 25 years of riding I've never liked that aspect of shifting myself, whether I'm riding my vintage friction shifter equipped ride or my Ultegra equipped ride. The only shifter that has accommodated this issue in the past that I am aware of was manufactured by Suntour. It mounted on the downtube, but not on the typical sides of the downtube. Instead, it mounted right between the two mounting points on the down tube. It was a novel idea that included a cam of some sort that acted when the rear shifter was moved hence moving the entire body up or down on the downtube (http://www.highertechpc.com/ebay/39.JPG) by only a fraction of an inch hence loosening the cable or tightening it thereby making up that minute adjustment. Here's the shifter (http://www.highertechpc.com/ebay/391.JPG). Hard for me to explain. Probably even harder to understand. In any event there may be something now that works in the same way.
Thank you for a very concise and informative post - you are a credit to BF!
I think that the low limit screw needs slight adjustment as when changing down on the FD it happens a little harshly; but other than that I am now confident all is ok!