View Single Post
  #9  
Old February 25th 06, 09:25 PM posted to rec.bicycles.tech
external usenet poster
 
Posts: n/a
Default Threadless BB Cartridges: Why/Why Not?

Andrew Muzi writes:

Thanks to Werehatrack for introducing me to the concept...
Now it begs the question:
Why are BB shells threaded in the first place?
i.e. Why don't most bikes just come with threadless
already installed?
Sounds like there's a downside...


I must have missed it but could you direct me to a web site where I
can see the cross section of a threadless BB? The only ones I know
of were on Ashtabula cranks and they had a larger diameter.


Surely, you recall the Mavic system of the eigties? Conical rings on
both sides screw onto a threaded Phil-ish cartridge. IN Mavic's
design, the frame gets milled with a 4mm chamfer on each end of the
BB. The later all-nylon-casing types (KSS brand) seem to work fine
without that chamfer.


I don't recall, and don't call me Shirley.

They are both more expensive to make and much more time consuming to
install. As such they can't be an OEM part and in today's world
that is a kiss of death. Low volume means high prices which leads
to low volume and therefore high prices, etc.


Picture reference please. I don't have much hope though because these
folks seldom show a cross section drawing where the function is
revealed. You might suspect they don't trust their patent protection.

Jobst Brandt
Ads
 

Home - Home - Home - Home - Home