BB Width for TA Chainset...Solved..I Hope

[Thame Game]

My frame is a Robert's with a 68mm shell and 16.5 inch rear stays.
Hubs are Mavic 577 8 speed 12-28 spread (26" rims)
Chainset is TA Specialities (6 bolt) 24/36/46

I've been on Sheldons site, but still can't get a definitive width for the BB axle.

Any gurus out there?

 

[jimo746]

Is there a bottom bracket fitted at the moment?

 

[hamster]

Looks like 115 here for a Shimano UNxx type bottom bracket...scroll down https://www.sheldonbrown.com/bbsize.html

 

[Thame Game]

Is there a bottom bracket fitted at the moment?

None.

 

[Thame Game]

Looks like 115 here for a Shimano UNxx type bottom bracket...scroll down https://www.sheldonbrown.com/bbsize.html

Sheldon gives me 133.5mm width for a TA Cyclotouriste MTB tripple. That to me seems MASSIVE for the bike?!?!

 

[Tootyred]

Just pop in whatever you have hanging around as a starting point and measure off that?

 

[mdvineng]

If it's the cyclotouriste 6 bolt then around 120mm bb .

 

[FluffyChicken]

Do you have a picture of the cranks. (just a check)

Given it's a triple and looking at the one on a pictures search then I would start at 127mm then go 132 or 122.5 as needed when you check chainline.
They use a TA 734 axle, but these are very asymmetric and are ~122/123mm iirc. Which back up going a bit longer to start with symmetrical bb's

If you have any to test, just try them. Always keep a 122.5 and a 113 bb around for testing.

 

[Thame Game]

Heres a few pics

 

[mdvineng]

https://velobase.com/ViewComponent.aspx?ID=19692C31-4452-4C95-AA38-F7DA41CDBAFA&Enum=115&AbsPos=414