Road Bike, Cycling Forums banner
1 - 5 of 5 Posts

· BrooklynVelo
Joined
·
1,426 Posts
Discussion Starter · #1 ·
Quick question regarding bb spindle length. I'm running a 68x110 square taper Shimano UN53, but I'll be swapping the parts over to a new frame soon. The new frame has Italian threading. I'm having a hard time finding a 70x110 for the square taper. However I have been able to find a 107 or 115 for a decent price. Which way should I go? Or should I just switch out the whole shebang and go Isis/Octalink for the new build?
 

· Registered
Joined
·
180 Posts
It depends on how much money you are willing to throw at the project. Your current BB is a pretty low-end component, so I'm not sure. I run an ISIS and have used Octalink in the past. The current trend towards external bearing cups is mostly a fad, I think, and will hopefully pass after a couple of seasons. Shimano has already abandoned their current design with next year's XTR component group. At any rate, it sounds like you don't mind doing some upgrading. If you're going to 9-speed or 10-speed, you'll have no choice, since the spacing is unique and requires the appropriate crankset. I don't believe square taper cranks are made for 9 or 10-speed.
 

· Premium Member
Joined
·
20,696 Posts
Here is what do..

The Dura Ace 7410 low profile cranks use a 103 BB. These have been out of production for years. 68mm NOS on Ebay are big bucks. Since 70mm isn't as popular, they don't cost as much. I buy 70 x 103 and use my 68 cups.

The cartridge is the same. It's only the cups that are different.

Can you find a 68 x 110 BB? If so buy any size 70 BB and use it's cups on the 68 x 110 BB..It's cheaper than going to Octalink
 

· BrooklynVelo
Joined
·
1,426 Posts
Discussion Starter · #4 ·
Thanks Dave. I can always count on you to think for me! Such a ...I should have thought of that moment... I'll just buy a 70x107 and use the 110 spindle from the 68. Man I should have thought of that. Thanks again.
 

· Banned forever.....or not
Joined
·
24,573 Posts
Unless you have little pedal/chainstay clearance, a 107 BB should work. It's only 1.5mm closer on each side. I managed to fit an Ultegra crank on a 107mm BB, when 115 was called for.
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top