Square Taper BB lateral adjustment

[p nut]

I need to adjust the bottom bracket spindle to the non-drive side by 3mm or so. This is on a project bike that I've been working on. The drive side crank arm has plenty of clearance, but the non-drive side barely grazes the chainstay.

This is on a steel MTB and currently has a ST BB. I was thinking of a few options:

1- Shave the drive side BB by 3mm. Fairly cheap (about $20). I will have to use a spacer in the future if I use modern cranks.
2 - Phil Wood BB. Phil wood said the BB is adjustable by 2.5mm either way.
3- Last, but what I think I will try--grind off the lip on the BB cup. Thread it into the BB shell by 3mm, then use blue thread locker (a la Phil Wood).

I think Option 3 seems like the best to me. I really don't want to shave the BB down, if I don't have to. And spending beau coup bucks on a PW (although it's VERY nice) seems too much. Grinding off the lip will be minimal effort (hopefully!). Phil Wood uses the same blue thread locker method on their BB's, so I'm guessing it's not a big deal. I just wanted to counsel together to make sure there isn't an issue I'm overlooking.

Thanks.

[oldpotatoe]

I need to adjust the bottom bracket spindle to the non-drive side by 3mm or so. This is on a project bike that I've been working on. The drive side crank arm has plenty of clearance, but the non-drive side barely grazes the chainstay.

This is on a steel MTB and currently has a ST BB. I was thinking of a few options:

1- Shave the drive side BB by 3mm. Fairly cheap (about $20). I will have to use a spacer in the future if I use modern cranks.
2 - Phil Wood BB. Phil wood said the BB is adjustable by 2.5mm either way.
3- Last, but what I think I will try--grind off the lip on the BB cup. Thread it into the BB shell by 3mm, then use blue thread locker (a la Phil Wood).

I think Option 3 seems like the best to me. I really don't want to shave the BB down, if I don't have to. And spending beau coup bucks on a PW (although it's VERY nice) seems too much. Grinding off the lip will be minimal effort (hopefully!). Phil Wood uses the same blue thread locker method on their BB's, so I'm guessing it's not a big deal. I just wanted to counsel together to make sure there isn't an issue I'm overlooking.

Thanks.

I don’t have a solution but gotta wonder why it’s ‘offset’ to the right or why LH arm has no clearance. Frame/BB issue? BB not proper BB for crank?

[merckx]

I would endorse option two. No reservations, and no cob job.

[p nut]

I don’t have a solution but gotta wonder why it’s ‘offset’ to the right or why LH arm has no clearance. Frame/BB issue? BB not proper BB for crank?

It's a Surly Pugsley fat bike, which has an offset rear end. Maybe that's why? I'm not sure.

I've also heard that some square taper BB's (in certain spindle lengths) are not perfectly symmetrical. i.e. Going from 107 to 109, they'd just add 2mm to the drive side (or something like that). That may be a factor as well.

[oldpotatoe]

It's a Surly Pugsley fat bike, which has an offset rear end. Maybe that's why? I'm not sure.

I've also heard that some square taper BB's (in certain spindle lengths) are not perfectly symmetrical. i.e. Going from 107 to 109, they'd just add 2mm to the drive side (or something like that). That may be a factor as well.

That’s why, no doubt. I’d say Phil BB or maybe Origin 8 which I think is chainline adjustable(gotta check that)....which crank and BB?

[CNY rider]

I would endorse option two. No reservations, and no cob job.

It's always easy to spend other people's money but I am agreeing with this 100 percent.

[choke]

Not only are the Phil BBs adjustable they also offer the option of an offset spindle.

[p nut]

That’s why, no doubt. I’d say Phil BB or maybe Origin 8 which I think is chainline adjustable(gotta check that)....which crank and BB?

Crank is White Industries VBC (road cranks). I'm trying to get the q factor as narrow as possible. I don't think Origin 8 makes a BB that I need. I'm currently using VP 100x147mm BB, which was really cheap. Which is why I don't mind messing with it.

Phil Wood is 2mm narrower at 145mm. It'll probably fit, but I don't know if it's too close for comfort. They do make 150mm as well, but it's a size they don't keep in stock, so it'll be 2-3 months before I can get one.

[p nut]

Not only are the Phil BBs adjustable they also offer the option of an offset spindle.

Per a PW employee, the spindles are supposed to be symmetrical. I don't have one, so I don't know. They may offset the smaller BB's, but for fat bike size (100mm BB), it sounds like they don't.

To note again, their adjustability comes from just moving the BB cups side to side and securing it in place with a thread locker. So pretty much the same thing I'm trying to accomplish by grinding off the lip...

[choke]

Per a PW employee, the spindles are supposed to be symmetrical. I don't have one, so I don't know. They may offset the smaller BB's, but for fat bike size (100mm BB), it sounds like they don't.

To note again, their adjustability comes from just moving the BB cups side to side and securing it in place with a thread locker. So pretty much the same thing I'm trying to accomplish by grinding off the lip...From the BB order page (https://phil-wood-co.myshopify.com/collections/square-taper-bottom-brackets/products/stainless-steel-square-taper-bottom-bracket-jis-taper-1) in the PW store: PLEASE NOTE: If you need your bottom bracket spindle to be offset please include this information in the notes section of your order.

A while back I was looking at buying a PW BB and I do recall them offering that option, at least on the length that I was looking at (this was on an older version of their website). IIRC they had 1, 2 and 3mm options for the offset.

[p nut]

From the BB order page (https://phil-wood-co.myshopify.com/collections/square-taper-bottom-brackets/products/stainless-steel-square-taper-bottom-bracket-jis-taper-1) in the PW store:

A while back I was looking at buying a PW BB and I do recall them offering that option, at least on the length that I was looking at (this was on an older version of their website). IIRC they had 1, 2 and 3mm options for the offset.

I will ask to be sure. Hope that's the case, but sure didn't sound like it when I called earlier.

[ultraman6970]

Which BB are you using???

did you try putting the BB backwards???

Maybe you have the wrong cups? seen guys putting thin and wide cups in the same set up and wonder why did not work.

[Kontact]

I'm considering doing option 3 to get a 7410 back in service.

I really don't see the downside to turning a relatively inexpensive BB into a Phil Wood format by sanding off the cup lip.

[dddd]

As a data point, I once had a Shimano cartridge bb with alloy cups that I must have overtorqued in on the driveside, since the alloy flange simply snapped off and was left hanging from the spindle during the first ride.

I simply removed the ring and re-torqued the opposite bb cup to secure the cartridge in place. I rode the bike on many rides for over a year, then sold it to a local who rode it for some years with no bb issues ever appearing.

I'll add that the internal tool splines were still extant after the flange snapped off, and that I used only grease on the threads.

[bikinchris]

Not only are the Phil BBs adjustable they also offer the option of an offset spindle.

This. Assuming the frame is straight and this is a design problem. Carefully measure the spindle length needed so you can order a Phil with a longer spindle on the left side. Then the adjustability of the Phil would finish the job.

[11.4]

I'd agree as well. Something's wrong if you can't make a standard commercial bottom bracket fit properly. Now those cranks have a reputation for not giving good chainline, so it's not the crankset I'd have recommended in any case, much less in a problematic alignment situation. If you're stuck with them, so be it. But perhaps grab another bottom bracket and crankset from Shimano or a major line and just see if it works ok. If your bottom bracket shell is a mountain one, be sure to use a mountain crank and bottom bracket to test with.

Of your options, neither is really acceptable. The Phil bottom bracket is a fix, but it'll drag your chainline out of alignment. Phil does make bottom bracket cartridges with all kinds of asymmetries to one side or the other, and with all kinds of axle lengths (hence Q factors) for any standard axle.

Is your problem that you're using a road 73 mm bottom bracket with a 76 mm or wider shell? Mountain and road do not have the same bottom bracket shells, even if the threading is the same. You simply shouldn't be having this problem. I'd be talking to Surly and getting them to help you with a fix. I'm suspicious of a misaligned frame or something in that vein. And are you sure the bottom bracket and crankset are both installed correctly? I haven't installed that bottom bracket, but a lot of them have extra spacers and other options that can mess up your installation if not chosen correctly. I think your problem is with an MTB bottom bracket shell and a MTB bottom bracket, or part of the funkiness of that White crankset.

Like Spud, I think there's something wrong here. It may be your choice of equipment -- as I said, I don't like those cranks for that reason. Don't face down your bottom bracket. That's irrevocable and if you then find you have a chainline or chainring clearance issue, you've screwed a frame. Talk to Surly, check the individual components (bottom bracket shell width, bottom bracket, and crankset) and test a different crankset and bottom bracket to see if it works correctly.

[p nut]

ultraman - the BB is English threaded, so can't swap sides.

11.4 - To be clear, this is on a Pugsley, which has a 100mm BB shell. The rear end is peculiar on these bikes, as they use standard 135mm rear hubs; however, it is all offset 17.5mm to the drive side.

Good thought about the chainline. I will have to measure that and see if it'll take it out of whack, and especially using road cranks. I don't believe the WI ENO rings are offset or have ability to flip, so adjusting chainline might be a challenge.

[bikinchris]

ultraman - the BB is English threaded, so can't swap sides.

11.4 - To be clear, this is on a Pugsley, which has a 100mm BB shell. The rear end is peculiar on these bikes, as they use standard 135mm rear hubs; however, it is all offset 17.5mm to the drive side.

Good thought about the chainline. I will have to measure that and see if it'll take it out of whack, and especially using road cranks. I don't believe the WI ENO rings are offset or have ability to flip, so adjusting chainline might be a challenge.

On some bottom brackets, you can swap the caps end for end.