Ultegra crank arm is very close to chain stay and front derailleur. Shop wants to install 1.5mm bottom bracket spacer. Is this ok with HollowTech II crank or is there another option?
by glia_enthusiast
Ultegra crank arm is very close to chain stay and front derailleur. Shop wants to install 1.5mm bottom bracket spacer. Is this ok with HollowTech II crank or is there another option?
by glia_enthusiast
6 Comments
For reference:
https://wheelsmfg.com/repair-pack-for-24mm-shimano-bottom-brackets.html
That is normal clearance. It will never touch the frame.
I don’t see how adding spacers helps with the front derailleur issue, since derailleur position is relative to chainrings. So 1,5 mm spacer would mean FD should be adjusted 1.5mm outwards as well.
Derailleur-crank on r8000 usually is close when set up correctly, and in my experience getting the height and angle of the FD right is key.
Simply put; spacer will help with frame clearance but not with FD clearance.
Generally speaking no, you cannot solve problems by adding arbitrary amounts of spacer on the spindle or under the cup of HT2 (road or mountain), because you’re robbing the spindle engagement on the NDS crank if you do that. The spindle engagement needs to be as intended. Could you get it to look like it works by doing that and maybe get away with it, maybe. Definitely don’t do it past the point where the NDS retention clip thing in the slot of the left crank can no longer engage the hole in the spindle. 1.5mm will likely be enough to go past that point.
There’s some other problem that’s creating this situation. Fix that.
Edit: The frame clearance thing is condeming in and of itself, that needs more gap one way or another, but also make sure the shop knows how to set up toggle FDs correctly. If they call them limit screws, that’s a clue they don’t.
Can you post a photo of the front derailleur and chainrings from the side?
Might be old school, but that’s not much seat tube / tire clearance for anything other than fair weather riding.