Bottom Bracket Plastic Sleeve?

In all my time I have nevery came across a plastic sleeve in a BB. However, last time I replaced mine with my then new then frame it was a perfect fit and a bit of googling suggested it would protect the BB bearings, so I left it in. However, ever since the bike has been silky smooth pedalling two legged sitting down but standing up or pushing off one footed it has made a loud honk (like squeaky brakes x 5) but no noticeable resistance. So tonight I took the sleeve out. What do you do with the plastic sleeve?

I am fairly certain that is what is causing the noise but if it continues I'll probably put the sleeve back in :scratch:
What type of of BB? Hollowtech BBs have a plastic sleeve but I can't see how this would cause any sounds.
  • Like
Reactions: C R
9x better on that ride, no one footed pedaling noise or when I threw the bike left right on a climb but there was still the occasional but quieter noise when I stood up. Which to me suggests it wasn't the sleeve but it does enimate from the BB I cleaned up :wacko:
Bearings are probably shot, they don't last long. Did you feel any roughness when the crankset was out?
Usually the left bearing fails first.
That's the thing I can't work out, they seem silky smooth, there's no play (my hip usually feels that) but its usually my right bearing that fails first and there no loss in performance. The BB order was only mid September last year so its only done 5,000 miles at the most but I'll keep an eye on things :okay:
Top Bottom