118mm bottom bracket, what’s it for?

[raymondluxuryyacht]

I found an 68 by118mm in my spares box. What group set or setups used these? I am thinking 7 speed era, but not sure if typical shimano set up with 135mm rear hub and 46 or 48 tooth outer chainring would have been ok with this. I mean 5mm difference to normal doesn’t sound much, but…..

 

[hamster]

It works well for those 122.5mm chainsets when put in a road setup...M730, M550 etc Also for older MTBs with a 130mm OLN rear.

 

[ishaw]

I think DX cranks used that length iirc, though could have been 122.

 

[hamster]

DX were usually 122, but if you had a 130 rear frame it would have been 118.

They also work right for Stronglight 80/99/100 or TA Zephyr on a road frame.

 

[SantasLoneCruzer]

The GT RTS Team I’m refurbing, came with. Royce (130mm) fitted, I’m confused why the spindle would be so wide???

 

[Frankenorange]

Sheldon Brown's website has a chainset/BB page and a list of loads of numbers. Search 118 in that page and i am sure it will throw a few examples up.

 

[legrandefromage]

My 93 zaskar runs about 127mm with an xt or top line chainset to get the arms past those fat stays

When low profile chainsets came in, axles got narrower

 

[hamster]

The GT RTS Team I’m refurbing, came with. Royce (130mm) fitted, I’m confused why the spindle would be so wide???

That depends on the chainset, but as LGF says it also may be necessary for clearance. Also low-band front mechs do not sit as close to seat tubes as high band - they often need a longer BB with 34.9 tubing.

 

[Splatter Paint]

They only exist to:
- confuse people buying bbs
- be fitted and cause issues, leading to a trip to the LBS, who then make money fitting the right bb
- rattle around in the bottom of spares boxes once removed from second hand bikes and take up valuable space
- cause moments of self doubt when you sling them in the bin, thinking I’m sure I’ll need that one day

 

[Takingabreak]

There is a database on Sheldons site, 118 fits quite a few cranks, many of them road triples

Sheldon Brown's Bottom Bracket Size Database

A database of bottom bracket sizes for various bicycles.

sheldonbrown.com