I'm replacing my old square taper bb and crankset with this hollowtech 2 (3x)crankset and compatible bottom bracket.
I've installed the the required spacer for 73mm shell on the drive side and I have also greased it up plentiful.
The crankarm slides on without much resistance and I've tapped it into the spindle multiple times just to be sure. I've tightened the preload cap just enough with two finger strength.
However the plastic safety tab is not sitting into the groove on the spindle in any way. I tried taking it all apart and starting afresh, making sure everything sits into place nice and firm and still it has about 3 to 4mm gap between the crankarm and the bb body. It allows for side to side play of the spindle along with the drive side crank when force is applied laterally. It's rideable but I'm not gonna ride it until it's properly installed.
Does anyone have something else to suggest or what I may have not thought of?
I've attached a video showing how much gap is present and how it moves side to side.
Shimano hollowtech 2 crankarm not sitting flush to the bottom bracket
byu/Jack_Harlow_2721 inbikewrench
by Jack_Harlow_2721
5 Comments
It looks like you need another spacer on the non-drive side.
I just recently replaced my BB, and shimano had pretty clear instructions on how many spacers to use on either side depending on your BB shell width and other factors. I don’t know your specific situation, but I have spacers on both sides of my BB.
measure the width of the frame where the bb sits (shell), if it is 68mm then add 2×2,5mm spacers to the drive side and 1×2,5mm to the non-drive side. If the shell is 73mm wide, then add 1×2,5mm to the drive side and none to the non-drive side
guys, this is my second bike build from scratch, i know stuff about bb shell width and spacers for respective shell width and in this case, it’s a 73mm shell therefore i have installed a 2.5mm spacer on the drive side as mentioned on the manufacturer label and as we all generally know.
the issue here is that if you see carefully, the plastic tab is extruding outwards from between the pinch bolt gap. that is supposed to be seated down to a point where you can’t notice it which happens when it is perfectly aligned with a hole in the spindle which ensures that the crankarm is pushed inwards enough to be tightened with the pinch bolts.
i’ve tried making sure that i pushed the crankarm onto the spindle quite well but still the safety tab doesn’t go down.
>hollowtech 2 (3x)crankset and compatible bottom bracket.
What’s the model number of your crankset? Bottom bracket?
If you are able to tighten the plastic cap with this gap, it means that the crank hits the end of the spline, which should not be the case. As suggested in our comment, double-check the compatibility of the parts.
You can not ride with this gap. Shifter will go crazy and bearings will be damaged with axial play pretty fast.