Changing Bottom Bracket
 

Hi everyone,
I want to change my bottom bracket. I own a 2011 Surly Long Haul Trucker. Would this bottom bracket fit: Shimano UN55 BB Square Taper Bottom Bracket. See https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1.

You may get more accurate responses in the Mechanics section ...

https://www.bikeforums.net/bicycle-mechanics/

The UN55 seems to be an upgraded UN54, so it should work fine.

68 x 118, according to Surly's spec sheet. http://surlybikes.com/uploads/downloads/2011_Surly_Catalog.pdf

Depends on the crank you have

The more important question is why do you want to change your bottom bracket. Unless it is malfunctioning...which seems unlikely for a 6 year old bottom bracket...you are probably going to be replacing like for like.

If you do have to replace it, that bottom bracket would work as long as you get the proper length. You'll have to pull the cranks and measure it to be sure.

Finally, you can do better on the price. A quick Google finds them for around $15. If you are going to pay full retail, you might as well get one at your local bike shop and help them keep the lights on.

Bottom brackets have to fit both the frame and the crankset. The UN55 bottom bracket is available in multiple threadings and shell widths to fit different frames and multiple spindle lengths to fit various square taper cranksets.

To fit your LHT's frame, you'd want an English-threaded 68 mm UN55 bottom bracket.

If you have a square taper crankset, you'd need to select a bottom bracket with an appropriate spindle length. Ideally, you'd measure your existing bottom bracket's spindle length and select a comparable replacement. Otherwise, you may be able to check your crankset's spec sheet. Or if you're visiting a shop in person, they can test-fit bottom brackets to confirm what fits.

Thanks Cyccocommute!

You get the tool to remove the one you have? then use it again to put a fresh one in , the BB is adequate..