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How and what do I need to remove bb71
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
After raceing at collie then cleaning my bike went to ride this morning to find the cranks very hard to turn over
After about 50 meters they were free again so I'm thinking mud or water has gotten in the bottom bracket
Bike is a Scott scale with a bb71
Wanting to learn and do myself what tools do I need to remove replace the bottom bracket and once out can you regrease or is it a through away item
Thanks
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Throw away item, not least of all because you don't want to be pulling pressfit out and putting them back in willy nilly
I have knocked them out carefully with a big socket on the end of a straight screwdriver type socket wrench with a mallet and tapping around slowly and patiently .
Same way back in. People usually recomend a bolt with washers and nuts to slowly tighten them in, but I personally found they didn't go in square with that method so used my eye a mallet and some degree of patience .
I just take my bike to the mechanic these days, $25 while you wait......
I'm hearing you but I'm a fitter machinist so wanting to learn and be able to do myself want to get to the point I can strip the bikes down to a bare frame and rebuild them each year but thanks
As the bearings are shot you just get a flathead screwdriver and give the bearing a slight tap on opposite sides until it starts to move. People cry about how difficult it is but with your background it should be easy.
If you can get the bearings out and the cups stay in the frame I'd leave it that way and just slap some new Enduro bearings in. I have alloy cups and just keep throwing new bearings in, mine only last a few months so it's a 15 minute job for me now.
It can certainly be done with hammer, screwdriver, sockets, bits of wood etc, but I've three bikes with press-fit BBs so I didn't mind investing in the proper tools. If you shop around you can get the Park BBT-90.3 set of extractor and fitting cups for about $50 online and add a bit of threaded rod & washers from Bunnings in place of a headset press and you're all set.
http://www.parktool.com/product/pressfit-bottom-...
Takes the variability out of it - who wants to muck up their BB shell for the sake of fifty bucks - and makes changing out a BB a breeze...
PS: I've replaced all the BB51/71s that came on my bikes with XTR level BB91/94s as they are sealed better, and at only $30 each I just treat them as a consumable and routinely replace at the annual service.
Thanks guys will go buy the tools and up grade any tips on crank removal it's xt tripple crank?
You'll need one of these for the non-drive-side crank -
http://www.chainreactioncycles.com/au/en/shimano...
And if you want to do a proper job (and it sounds like you do) a torque wrench for re-fitting the clamp bolts.
Then just follow any of the online guides how to do it, like this for example...
http://www.pinkbike.com/news/technical-tuesday-s...