Question on STI Shifter
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My bike has Ultegra 9 speed with STI Shifters. When shifting from the small chainring to the big chainring, the front derailler has 3 positions. Inner, center, and outer. However once in the big ring, I can not shift the derailler into the center position. It goes from the outer most to inner most position with no stopping in between.
Is there an adjustment, or something I can look for?
Thanks,
Dennis
I'm not an expert on STI trim positions -- someone else should chime in -- but in my experience, it is typically difficult to accurately shift into the next minor trim position down. I seem to think I can do it, but only with a crazy light touch and a little luck.
Like you, I find that going up (against the spring) through trim positions is easy to do with accuracy.
Who can clarify?
Originally posted by lokstah
I'm not an expert on STI trim positions -- someone else should chime in -- but in my experience, it is typically difficult to accurately shift into the next minor trim position down. I seem to think I can do it, but only with a crazy light touch and a little luck.
Like you, I find that going up (against the spring) through trim positions is easy to do with accuracy.
Who can clarify?
its not trim its adjustment, its just off it sounds if he has a tripple and is skipping the middle ring all together, btw theres no trim position between big and middle
Originally posted by fushman
its not trim its adjustment, its just off it sounds if he has a tripple and is skipping the middle ring all together, btw theres no trim position between big and middle
I don't quite follow what you mean. The bike is a double. Going from small to big, the derailler can stop in 3 positions. Going back to small, it wont stop in the center.
I have another bike with 105 and it works properly. Just not sure why it doesnt on my Ultegra bike.
Dennis
Originally posted by tridennisr
My bike has Ultegra 9 speed with STI Shifters. When shifting from the small chainring to the big chainring, the front derailler has 3 positions. Inner, center, and outer. However once in the big ring, I can not shift the derailler into the center position. It goes from the outer most to inner most position with no stopping in between.
Is there an adjustment, or something I can look for?
Thanks,
Dennis Ya got a double or triple crankset?
Originally posted by boudreaux
Ya got a double or triple crankset?
Its a double.
Thanks,
Dennis
Originally posted by fushman
...btw theres no trim position between big and middle
There sure is between small and big on a double. Boudreaux?
Originally posted by lokstah
There sure is between small and big on a double. Boudreaux? There is trim for the small ring and trim for the big ring. There is no 'between' with a double.
Originally posted by lokstah
There sure is between small and big on a double. Boudreaux?
cause a doble has the big 52-53 ring position blocked so you cant tell unless youve got a tripple or know, there isnt any trim position between the big and middle chainwheels on a sti triple set up
Originally posted by boudreaux
There is trim for the small ring and trim for the big ring. There is no 'between' with a double.
Not sure why those don't qualify as 'between' positions. Clarify?
Originally posted by lokstah
Not sure why those don't qualify as 'between' positions. Clarify? There are chainring positions in the shifter and trim positions. Between means something else in my head and does not compute.YMMV
Originally posted by boudreaux
There are chainring positions in the shifter and rim positions. Between means something else im my head and does not compute.YMMV
Lost in translation?
Between in my dusty head is a reference to the physical position of the derailleur -- in this case, bound between the upper and lower shifter positions for the big and small rings.
I think what I've said makes enough sense, but what does it matter? I'm scratching my head too. We could battle over semantics all night, and you'd probably win because everyone knows that your general knowledge of drivetrain mechanics (and terminology) bests nearly everyone else here -- or you could just try to help Alex. I didn't have an answer. Do you?
Originally posted by lokstah
Lost in translation?
Between in my dusty head is a reference to the physical position of the derailleur -- in this case, bound between the upper and lower shifter positions for the big and small rings.
I think what I've said makes enough sense, but what does it matter? I'm scratching my head too. We could battle over semantics all night, and you'd probably win because everyone knows that your general knowledge of drivetrain mechanics (and terminology) bests nearly everyone else here -- or you could just try to help Alex. I didn't have an answer. Do you? The derailer positions are controlled by the shifter. So the positions are really in the shifter. With an ultegra 9 speed,when set up for a double, the granny and middle ring positions in the shifter are used.When in the the small ring, a small left movement of the brake lever moves the derailer to the right so it doesn't rub when in the smaller cogs. Shift to the big ring, and the trim is in the small lever, a light touch of which moves the derailer to the left so it doesn't rub when in the bigger cogs. When with a triple chaiset, things work the same but for the small and middle ring,but there is no trim for the big ring.
Originally posted by boudreaux
The derailer positions are controlled by the shifter. So the positions are really in the shifter. With an ultegra 9 speed,when set up for a double, the granny and middle ring positions in the shifter are used.When in the the small ring, a small left movement of the brake lever moves the derailer to the right so it doesn't rub when in the smaller cogs. Shift to the big ring, and the trim is in the small lever, a light touch of which moves the derailer to the left so it doesn't rub when in the bigger cogs. When with a triple chaiset, things work the same but for the small and middle ring,but there is no trim for the big ring.
Ok, now we're talking. Thanks for the explanation; that's basically what I understood, and what I think Alex basically understands as well, though now it's a touch clearer.
I think the crux of Alex's question was, though, why the trim position comming down off of the big ring on his double is difficult or impossible to nail -- he can't tap it light enough, and he always flies down to the first small ring position.
What's the deal? I know that position to be tough to get to on doubles I've owned as well.
Originally posted by boudreaux
Shift to the big ring, and the trim is in the small lever, a light touch of which moves the derailer to the left so it doesn't rub when in the bigger cogs.
Yes, this is exactly what I am trying to describe. I don't seem to have this trim position in the small lever. Do you know if this is servicible?
Truth is I don't use it much as I prefer not to cross the chain that much. However I sometimes do for a very short time and would like to fix this.
Thanks for your help,
Dennis
Originally posted by tridennisr
Yes, this is exactly what I am trying to describe. I don't seem to have this trim position in the small lever. Do you know if this is servicible?
Truth is I don't use it much as I prefer not to cross the chain that much. However I sometimes do for a very short time and would like to fix this.
Thanks for your help,
Dennis Assuming the shifter is not defective,the hi limit screw could be set too tight.Cable tension might be an issue. Best way to deal with derailer adjustment is start at the beginning and go through the whole drill. www.parktool.com has how to in the repair section. If the bike is new, the shop should take care of it.Since Your 105 works as it shoud,technique is not the apparent issue.
Check your cable tension, should have a bit of slack on the Inner Chainring. This will directly effect Trim.
IMHO
Originally posted by Snarl
Check your cable tension, should have a bit of slack on the Inner Chainring. This will directly effect Trim.
IMHO It's more likely to prevent a shift to the big ring, and lack of or inadequate trim when in the small ring.
Originally posted by boudreaux
Assuming the shifter is not defective,the hi limit screw could be set too tight.Cable tension might be an issue. Best way to deal with derailer adjustment is start at the beginning and go through the whole drill. www.parktool.com has how to in the repair section. If the bike is new, the shop should take care of it.Since Your 105 works as it shoud,technique is not the apparent issue. I did an experiment on one setup and found that the high limit could indeed be set too tight. Shift to the big ring was ok,but no trim. Backing our the hi limit screw about 1/4 turn restored trim and resluted in no thrown chain.
Originally posted by Snarl
Check your cable tension, should have a bit of slack on the Inner Chainring. This will directly effect Trim.
IMHO
That took care of it. I just loosened the cable tensioner a few turns and it works. Still shifting into the big ring fine.
Thanks for everything guys,
Dennis
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