67mm BB shell, what to do?

[lukeheller]

Steel frame, "elephant randonneuse" under custom bikes section for reference

I just decided to switch back to square taper and ordered up a 68mm x 113 Tange BB. I slapped it on and noticed that the BB has about 2 threads, or 1mm, exposed on the NDS. How big of a problem is this? More importantly, what's the solution?

I used a cassette spacer and put it on the driveside. That seemed to work out the BB issue to my satisfaction but now the chainline is kinda concerning. However, I can't put the spacer on the NDS because there's no lip on the NDS tange BB cup like there is on Shimano NDS BB cups. Would I be better off getting my hands on a Shimano NDS BB cup and putting the spacer there?

Pic 1: shows 67mm measurement
Pic 2: shows exposed threads
Pic 3: shows spacer added to driveside

Any recommendations/experiences?

Thanks

[PJN]

Ride the hell out of it.

[Brian Smith]

Life's good, here's why:
While the 67mm shell might give problems to some contemporary bottom brackets, it won't for your cartridge BB.
A 1/2 mm spacer could be sourced (Wheels Mfg. does them) but I wouldn't recommend using one unless you really knew that your chainline, as measured or as determined in use and not simply theorized, needs to be modified.
The cup without a lip doesn't have to thread all the way in and only as far as the edge of the frame. It can remain far enough in or out of the shell to accommodate a few mm of chainline tuning. If the crank chainline doesn't matter in your application, the 1/2 mm (and this product is not 0.5, it's 1/2!) spacer may give you aesthetic resolution.

[thirdgenbird]

I agree with the above, ride it!

I had a unique occurrence where i mixed an Italian Ofmega bb spindle with English Campagnolo cups. The width was about 2mm off and I used a spacer and it worked great. I your case, not worth sweating over.

Outboard bearings would be a different story.

[rice rocket]

Why all the hate on outboard bearings?

Add a 1mm spacer, boom.

[Ralph]

No big deal. Both my square taper bikes have a couple threads showing on non drive side with Campy cartridge BB's. Use the spacer only if you need to adjust chainline....or clear the drive side chain stay.

[lukeheller]

Life's good, here's why:
While the 67mm shell might give problems to some contemporary bottom brackets, it won't for your cartridge BB.
A 1/2 mm spacer could be sourced (Wheels Mfg. does them) but I wouldn't recommend using one unless you really knew that your chainline, as measured or as determined in use and not simply theorized, needs to be modified.
The cup without a lip doesn't have to thread all the way in and only as far as the edge of the frame. It can remain far enough in or out of the shell to accommodate a few mm of chainline tuning. If the crank chainline doesn't matter in your application, the 1/2 mm (and this product is not 0.5, it's 1/2!) spacer may give you aesthetic resolution.

So... remove the driveside spacer, leave the exposed threads on the NDS, and ride on?

[thirdgenbird]

Why all the hate on outboard bearings?

Add a 1mm spacer, boom.

I wasnt hating on them. They are not as forgiving in situations like this.

[wallymann]

...when using a cartridge BB. if your chainline is OK, no issues whatsoever.

[cmbicycles]

This is common that the NDS cup a non-external BB doesn't thread in all the way. There are almost always a couple threads showing for just about any manufacturer. Phil Wood BB's don't have a lip on either cup, if that informs you of the relative importance of having a lip or not. They make theirs that way so you can easily adjust your chain line. Shimano's nylon NDS cups have a slightly raised area, but that is there to reinforce the end of the cup, and it usually sticks out a thread or two as well.

Yup, remove spacer, especially if it messes up your chain line like you stated, and ride with a smile. Just make sure it is properly torqued... preferably with a torque wrench per manufacturer instructions (my OCD requires this for my bikes), or the old German torque spec... Guten Tight.

[seat_boy]

Yeah, I've had an exposed thread like that before and just lived with it, no issues.