« Recent Email Regarding Campagnolo Ultra Torque | Main | Radio Check.... »

February 17, 2012

TrackBack

TrackBack URL for this entry:
http://www.typepad.com/services/trackback/6a00d834525fac69e201676281ead3970b

Listed below are links to weblogs that reference Review of Lennard Zinn's "Adapt This!":

Comments

RogueMechanic

Hello again Pierre!
Herein lies the problem! Some crankset designs work better than others with the press fit BB's. I've gotten reports of some bad cup movement with the UT press fit cups... I do not like to make the assumption that the Bottom bracket is round and square... they want us to just trust that they are. Did you see the post I did about the Cervelo R5 with the BBright pressfit bottom bracket? If not, you might enjoy checking it out. Thanks again for writing! -John

Pierre

Dear John,

I am following up on my recent comments on the ultra-torque issue. It indeed has a common point with the present post : the pressfit bearings.

All modern BB systems have those, including the megaexo one with its bearings in external cups.

How do you keep pressfit bearings in place ? By applying an axial load on them (i.e. blocking one of the rings or preloading the entire bearing).

Where is this achieved ? On all headsets.

And where is this very imperfectly achieved ? On all modern BB's ... None of them are fitted with a proper blocking or preloading system, aren't they ?

Maybe i'll go back to my cup and cone systems ...

Cheers, Pierre

The comments to this entry are closed.

RM Store

Tweet!!

Client Testimonials...

  • A.R. said...
    " Dear John, I got out tonight for a quick ride... The Trek ran like a top, like butter on a hot skillet, smooth like a baby's bottom, like a shot of Johnnie Walker Blue, . . well you know what I'm trying to say, like a brand spanking new 5.9 Madone! Thank you again for another job well done! Your grateful customer and greatest billboard, A.R"
  • PR said...
    "My search for a highly qualified, honest and reliable bike mechanic is over. Not only is John (RogueMechanic) a superb mechanic, he is also very knowledeable about equiptment... I have never been disappointed."
  • Dr. M said...
    "John is a top flight mechanic. His knowledge, expertise and superb customer service surpasses everyone else... His personal integrity and high standards are reflected in his work on my bikes..."