Just got a set of power cranks. I have a shimano BB7700 with a length of 109.5mm. My chain rings are 53/39.
After installing the PC my front derailleur can no longer shift to the big chain ring and repositioning it will not give it the distance to shift.
The cranks are definately set into the spline deep enough and aligned. Anyone have these issues with PC’s? and how were they resolved?
You call Frank and Andrew?
Dave
Not yet. Figured I would give it a shot in the dark here before I called.
Just got a set of power cranks. I have a shimano BB7700 with a length of 109.5mm. My chain rings are 53/39.
After installing the PC my front derailleur can no longer shift to the big chain ring and repositioning it will not give it the distance to shift.
The cranks are definately set into the spline deep enough and aligned. Anyone have these issues with PC’s? and how were they resolved?
If you called me I would suggest they were not installed on the splines correctly, so not seated all the way, or you have a triple spindle. If you are sure they are and your spindle is 109.5 then all I would do now is shrug my shoulders as this is the first I have heard of this problem. Let me know when you figure out the problem so I can put it in the computer for the next time it comes up.
since you did not mention it . . . .
you HAVE backed the FD’s big-ring set screw all the way out, correct ???
Yeah, I backed it out. Figured out the problem though. Which had the same effect of what you mentioned.
My FD was gucked up. I should have noticed that when I backed it out it didn’t move 
I took the FD off gave it a good cleaning backed out all the L screws and put it back on and retuned it.
It’s working now, pretty tight, but I can dial it in better when I have some more time.
Another case of too many bikes and not enough time to spend what I would like to on maintenance.
Thanks Frank, sometimes a “shrug” is the best advise to force you to look elsewhere.
BTW, been riding with them in the small ring for a week now. They are certainly humbling, in a good way though. I have already worked my way up to a little over an hour and there is little question as to the benefits.
If by “reposition” you mean you lowered the FD, you will probably have to take up some cable slack to get it to shift to the big ring. If the move was small, the barrel adjuster might do it. If not, detach and reattach the cable.