ISIS bottom bracket

figbat
figbat Posts: 680
edited January 2017 in MTB workshop & tech
My venerable 2007 Kona Caldera has been bulletproof over the last 9 years, still being on the original BB and wheel bearings, despite much neglect. However this week I noticed that the BB is a bit loose and rough running, so it'll need sorting. It has an "RPM ISIS" BB with FSA AlphaDrive crank. I have found somewhere to borrow the tools from but having never done one before, was after some hints, tips and advice.

I gather it can be tight to get off (especially since it has never been off, and this bike has been BB-deep in water frequently). I plan to use an anti-seize compound or grease on refitting. Do I also grease the splines for the crank arms?

And which BB should I go for? Reviews of the common ones on CRC and Wiggle are mixed, but I don't want to spend a fortune on it. Is there a hidden gem out there that is cost-effective yet reliable? Is there anything I can do during installation that might extend the life of a BB? Pack with grease?

Or is this a time to consider some kind of conversion to another BB and crank type, if such a thing is possible?

It gets use 2-3 times a week, 15-25 miles at a time, all off-road, all weathers, trails/byways/bridlepaths/single-track on and around the Ridgeway in South Oxon.
Cube Reaction GTC Pro 29 for the lumpy stuff
Cannondale Synapse alloy with 'guards for the winter roads
Fuji Altamira 2.7 for the summer roads
Trek 830 Mountain Track frame turned into a gravel bike - for anywhere & everywhere

Comments

  • The Rookie
    The Rookie Posts: 27,812
    The bike has a common English Thread BB so you have a stack of choice.

    If you want a complete crankset then the Shimano Deore setup with HT2 external bearings is a great value option at about £50.

    No need for grease on the splines but some on the threads is worthwhile (whatever BB you use).
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • rockmonkeysc
    rockmonkeysc Posts: 14,774
    Googling ISIS will put you on an FBI register.
    As recommended above, the Deore HT2 crankset is great value and top quality.
    Transition Patrol - viewtopic.php?f=10017&t=13070235
  • The Rookie
    The Rookie Posts: 27,812
    As the FBI only operates internally to the US I wouldn't be overly concerned by that.....besides you would be one in hundreds of millions!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • figbat
    figbat Posts: 680
    Just to close this out, I got a FSA Platinum b/bracket, which went in nicely and is lovely and smooth. The only slight issue is that when it was fitted the chainrings were in an ever-so-slightly different position compared to the original BB (perhaps 1 mm closer to the frame) meaning I had to faff around with the front mech to get it all shifting cleanly with minimal chain rub at the extremes.
    Cube Reaction GTC Pro 29 for the lumpy stuff
    Cannondale Synapse alloy with 'guards for the winter roads
    Fuji Altamira 2.7 for the summer roads
    Trek 830 Mountain Track frame turned into a gravel bike - for anywhere & everywhere

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