RADBMX.CO.UK

Technical & Reference Section => Tech and Restoration => Topic started by: McQUEEN on February 12, 2017, 07:47 AM

Title: 28tpi bottom brackets
Post by: McQUEEN on February 12, 2017, 07:47 AM
Is there a difference between a 28tpi bottom bracket set for a one piece crank and a 28tpi bb for a three piece crank?

I've a Tange CV-170 bb axle and only seem to find bb's at that thread pitch for one pieces?

Thanks in advance....
Title: Re: 28tpi bottom brackets
Post by: steve69 on February 12, 2017, 08:23 AM
Yes, I believe the 3pc 28tpi bottom bracket diameter is smaller but I don't have conformation to hand right now.

(I'm in need of a 28tpi bb outer lock nut for a 1pc if anyone has one, would take a whole bb if I have to)
Title: Re: 28tpi bottom brackets
Post by: kalex on February 12, 2017, 08:40 AM
Not sure if I'm on the same wavelength but I'm sure I've used a mongoose 28tpi opc bb on redline 401's double dimple spindle
Title: Re: 28tpi bottom brackets
Post by: factory pilot on February 12, 2017, 09:22 AM
Not sure if I'm on the same wavelength but I'm sure I've used a mongoose 28tpi opc bb on redline 401's double dimple spindle

I've definitely heard of this being done ... It's a dilemma when using a 401 crank ... Techmatics are far too late ( 87/8 ) for most OS builds
Title: Re: 28tpi bottom brackets
Post by: steve69 on February 12, 2017, 09:24 AM
Not sure if I'm on the same wavelength but I'm sure I've used a mongoose 28tpi opc bb on redline 401's double dimple spindle

Yes, the 401 bb is a regular 1pc bb. The Tange CV-170 that's spoken of I'm sure is a much narrower square drive unit
Title: Re: 28tpi bottom brackets
Post by: kalex on February 12, 2017, 09:33 AM
Not sure if I'm on the same wavelength but I'm sure I've used a mongoose 28tpi opc bb on redline 401's double dimple spindle

Yes, the 401 bb is a regular 1pc bb. The Tange CV-170 that's spoken of I'm sure is a much narrower square drive unit

I did say I wasn't sure I was on the same wavelength  :D
Title: Re: 28tpi bottom brackets
Post by: steve69 on February 12, 2017, 09:42 AM
I just dropped a quick search to make sure I wasn't talking out of my backend. It would seem you need a 24tpi (not 28) but it does look smaller as I suggested.
SimplePortal 2.3.5 © 2008-2012, SimplePortal