Square Taper BB question
 

So I just ordered the Sugino Alpina 2 triple cranks (JIS) and am now planning my BB purchase. According to Bicycle Touring News it requires a 110mm spindle

My issue is that I am looking to get a Phil Wood BB and I can only get it at my shop through one distributor and they only have them in a 108 or 113mm length in JIS. So I am wondering with the cups which are supposed to give 5mm of adjustment on the chainline should I go 108 or 113 or is all of this a bad idea and I should try and find one in 110 length?


In case this is at all needed I will be running a Deore XT 9 Speed SGS RD (M772) with a 11-34 cassette on a Co-Motion Cascadia. Thanks in advance for any help and opinions.

Could you test fit a UN55 in a 110 before spending the big bucks? While Bb spindle length claims are a good starting point sometimes a bit longer or shorter fits better. Andy.

You might consider getting an SKF in 110, it has better bearings and seals, and a 10 year warrantee compared to the Phill's 1 year.

There are 3 things to consider: 1) chain stay clearance, 2) tire clearance, 3) chain line. Also, square taper BB don't always come out centered on the BB shell, so sometimes a small adjustment is needed. #1 is the most likely problem. Otherwise 2mm isn't very significant and is unlikely to cause a problem.

A good retailer will allow an exchange if you haven't ridden it and it is in a sellable condition.

Phil BBs don't use a flange on the right cup, so they can be floated a few mm's to either side.

Note, you don't need to move them by the difference in spindle length, but only half that or about 1mm or so if you buy either the 108 or 113mm version.

I might could buy one or even the cheaper version since returning would be a pain.

I might look into the SKF a little more. I haven't heard anything discouraging. Though I cannot order them via the shop I work at.
Returns are a hassle since I am not buying it via retail but the distributors via my bike shop.



Makes sense.

The only potential problem with going shorter, even if the chainline is adjustable, is that the non-drive side crank arm may hit the chainstay if you move the spindle toward the driveside. I ran into this problem on an old Trek MTB.

and.. the current Phil BB use a machined aluminum sleeve with shoulders for the bearings,

And a precise press fit between the bearing ID and the spindle diameter.

It is possible to pull the spindle through the bearings, and slightly adjust the offset of the spindle/axle

to be more or less symmetrical .. so 2 ways to tweak the chainline .. So, of the 2 A 113 would be a better choice


Add their optional, dust covers to further shield the bearings against contamination ..

they fit in the mounting rings .

Thanks.

Gotta go with the dust covers they have that oh so loverly Phil logo. Something about it just politely utters class with a loud enough voice to be heard but not loud enough to disrupt a social function with improper manners.

If I were sure about the 110, and you want the Phil Wood, I'd go with the 108mm... unless the crankarm will definitely not clear the chainstay. I honestly don't think that a 1mm difference in chainline is going to be an issue. It's a triple, 2 of the 3 chainrings will have a crappy chainline anyway.

Another way is if you go with a 113mm, you can probably add a .5mm or slightly thicker spacer between the cassette the the freehub body to move it out a tiny bit and get a little better chainline. There is a slight difference in total overall width between 9 speed and 10 speed cassettes so you have a tiny bit of room to work with.

If you are really concerned, just pick up a cheap sealed square taper bb with a 107mm spindle and test out different spindle lengths. You don't have to screw the right side of the bb all the way in to take measurements.

John