Hi after finding my current shimano bb giving up the ghost after only 9? months I invested in a skf über expensive bb.
The installation blurb is a bit ambiguous to say the least! My main points of confusion are:
1. the bb fits 73mm shell and has a spacer for 68mm. Does the spacer go drive side?
2. The non drive side screw in cup doesn't push on the bb shell like a UN5*. It'll slide all the way up to the DS (when not installed). What the hell is going to hold the bb in place.
regards m.
SKF BB Installation.
Re: SKF BB Installation.
if the spacer is 2.5mm thickness and the bearing unit is located laterally on the drive side, that is where the spacer goes on a 68mm shell. (However if the spindle is a different length each end or you have a funny crankset, or you need to adjust the chainline, you might wish to install a thinner spacer instead).
If the LH cup is a sliding fit on the BB cartridge itself, it just means that the LH cup accepts radial loads but not lateral loads. Quite a few BB units work like this, including many shimano ones.
cheers
If the LH cup is a sliding fit on the BB cartridge itself, it just means that the LH cup accepts radial loads but not lateral loads. Quite a few BB units work like this, including many shimano ones.
cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
- recordacefromnew
- Posts: 334
- Joined: 21 Dec 2012, 3:17pm
Re: SKF BB Installation.
Assuming the skf is also JIS, the quick and dirty way to determine spacer requirement for maintaining chainline is to stand it next to the UN with the drive side at the bottom and see what size if any spacer(s) on top of the flange would reach the same height as the old one (with or without spacer as previously installed). This does rely on the tapers being exactly the same (which is rare if you want to be precise).
How did you decide which skf spindle length to go for, given they don't have the same spindle (a)symmetry as the UN's of the same length?
How did you decide which skf spindle length to go for, given they don't have the same spindle (a)symmetry as the UN's of the same length?
Re: SKF BB Installation.
recordacefromnew wrote:How did you decide which skf spindle length to go for, given they don't have the same spindle (a)symmetry as the UN's of the same length?
The limiting factor in this case is the chain ring teeth almost touching the chain stay, so I picked a length that's a tad wider than the UN (taking into account that the skf "comes up wider").
I never really understood why some BBS are asymmetrical!
Thanks both for the info'
M.