Shimano BB71-41B Press Fit Road Bottom Bracket

[tincaman]

Any idea how to remove this, preferably without destroying it?

 

[Yellow Saddle]

Removal is generally destructive, even with the right tool.

 

[tincaman]

Maybe one of these two?
I want to get it out complete and Loctite it as it creaks
There is a 24mm version of the 2nd one, the 30mm would be too big

 

[Yellow Saddle]

Maybe one of these two?
I want to get it out complete and Loctite it as it creaks
There is a 24mm version of the 2nd one, the 30mm would be too big

I have the latter in the Shimano version. 9 out of ten times it destroys the BB. I've never tried the top one even though I have one for use on headset inserts. I suspect it will also damage it. Cyclus tools makes a nice remover that doesn't damage the BB for the price of the tool you can buy about 30BBs, I once calculated.
I don't want to piss on your battery, but you'll never get a pressfit BB to be quiet for long. Loctite doesn't work. The engineering is completely wrong for the job. A pressfit joint in a device that precesses in use just doesn't work.

Of course the brochure for your bike didn't tell you that, it only spoke of weight savings etc. I'm afraid you just have to live with it. I know you won't like that advice.

 

[tincaman]

Both my bikes are press-fit, so its worth a try. In the end I punched it out with a straight 10mm steel rod, with no apparent damage. It is now reassembled with Loctite 641, will give it 24hrs and give it a go. My old Scott CR1 had press-fit, and I did three years with that bike with a quiet BB.
I have a spare BB on standby............ Kudos to Merlin Cycles for supplying it, cheapest price around and delivered next day for free.

 

[fossyant]

This is all brutal stuff isn't it. Think bike designers need to re-think again. Careful tapping can get stuff out, but it isn't for the ham fisted.

 

[tincaman]

330 miles after refitting with Loctite 641, all is silent

 

[S-Express]

This is all brutal stuff isn't it. Think bike designers need to re-think again. Careful tapping can get stuff out, but it isn't for the ham fisted.

Agreed. What's needed is some kind of threaded BB design. Oh..

 

[Levo-Lon]

Had to do my press fit bb today..it was knackered..less than 500 miles..bit dissapointed as its a 3k bike..
all the wheel bearings and now the BB in a year..just the pivot bearings to fail now.tho they seem good as yet

 

[Yellow Saddle]

Had to do my press fit bb today..it was knackered..less than 500 miles..bit dissapointed as its a 3k bike..
all the wheel bearings and now the BB in a year..just the pivot bearings to fail now.tho they seem good as yet

Don't smoke that cigar quite yet. Remove the chain and one shock eye. Now the rear suspension spaceframe can move up and down freely and you will be able to feel any notchiness in those bearings. Because they don't rotate like wheel bearings, a major notch develops in the sag position where the suspension does most of it's micro movements.
But then again, why spoil your Saturday?

 

[Levo-Lon]

Don't smoke that cigar quite yet. Remove the chain and one shock eye. Now the rear suspension spaceframe can move up and down freely and you will be able to feel any notchiness in those bearings. Because they don't rotate like wheel bearings, a major notch develops in the sag position where the suspension does most of it's micro movements.
But then again, why spoil your Saturday?

i very nearly did the check yesterday....ill have to check them now