bikerumor monday mystery pic first flight bicycles mombat

Photo from the collection of Jeff Archer of First Flight Bicycles. If you think you know what this is, post your answer in the ‘comments’ section– the correct answer will be posted there on Tuesday!

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  1. Yes I agree, Mavic Bottom Bracket for shells with stripped or damaged threads.could also adjust chain line.Great Mavic Quality.

  2. Mavic 610 bottom bracket. Needed a specific chamfering tool so it could be used and installed properly. I still have one and the tools. Worked beautifully but weighed a freaking ton!

  3. Yeah, Mavic’s old BBs – I still have one mounted in an old Trek 8700 frame, alloy/carbon from 1991.
    Damaged the BSA thread on that frame, so the Mavic was the only solution after that.
    Wish they’d still make those rather than helmets and stuff.

  4. @Matt, there are aluminum sleeves with BSA threads that you can press into a BB30 frame with a headset press, they aren’t easy to get out if you ever decide to run a BB30 crank though.

  5. Yup, it’s a Mavic BB. I have one on my 1983 KHS Professional. Swapped the original Superbe Pro Crank for the lighter, stiffer, and oh-so beautiful Mavic Crankset. The bike currently runs on the original derailleurs and brakes, Shimano 7sp shifters and freewheel, Campy Record hubs and seatpost, and Modolo brake levers. And yes, the all play well together!

  6. Mavic’s worst invention ever. An anuglar pressure fit bb that required you to mill your frame to accept it. I had to use green loctite all the time on mine to keep it from moving under extreme loads. The only good thing about that BB was the ability to dial in the chainline.

  7. Great BB! Now who has the shop tool kit from Mavic for chamfering the bottom bracket shell, adjusting the hubs, removing and installing the sealer cartridge bearings from these wonderful parts? Yea, that would be me!

  8. @royalwithcheese
    Lesson I learned the hard way. If your PF shell isn’t perfectly round, then there’s no way for the aluminum shell to fit into it.

    …but not being perfectly round it kind of the whole point of pressfit. You can be slightly off and PF still works find. Would love to find a non-permanent solution for a pressfit squaretaper.

What do you think?