Madone 4 External BB spacers 0.6mm

Bengdogg
Bengdogg Posts: 383
edited January 2013 in Workshop
When I had my madone 4 which I think was 2010 it had a spacer behind the bb 0.6mm thick and larger than the ultegra cups, I have since changed the bb twice once for a cheap ceramic BB that kept developing play so I got rid of that and have fitted a Dura Ace BB to the bike, The width from of the BB is exactly 91mm and the chainset seems to be bang on 43.5mm to the centre of the two chainrings but I cant help but feel I may of done something wrong as every trek madone picture I see has this spacer fitted on models that pre-date press fit. The cranks clear the frame fine and everything runs well with no play in the cranks or bearings. I can get 9 out of ten gears in the inner ring before the ramps start to tick on the chain ready to pick up which has always been the case as it's not a ration I would use in normal use outside of testing. In the outer chainring all 10 gears work fine.

Needed or not??? I think not but any advise will be taken into consideration and appreciated.

Thanks
You just gotta peddle

Comments

  • Bengdogg
    Bengdogg Posts: 383
    http://4.bp.blogspot.com/-yRxjLYXu10Y/T ... earing.jpg

    This is the spacer I am on about, see how it is bizarrely large in diameter...

    I have a theory this is to help deflect the chain in the event of a drop and protect the paint & BB shell. I run a chain catcher anyway and those alloy stick on deflectors came off my frame long ago (just dropped off/unstuck) I replaced it with a bit of lizard skin stuff just in-case but then went down the catcher route
    You just gotta peddle
  • smidsy
    smidsy Posts: 5,273
    No spacers required for Shimano HT2 BB on road bikes.
    Yellow is the new Black.
  • Bengdogg
    Bengdogg Posts: 383
    That's exactly my understanding too. I think its part of an emergency chain protection set up.
    You just gotta peddle

Categories