Broken bottom bracket ST1

Accelerating away from a green light, something was immediately wrong as I was only standing on my right pedal and my butt was on the top tube. I pulled over and found that my left crank arm was 50 ft back in the middle of the road (not in my spd shoe) and my frame was showing an exposed bottom bracket with a few ball bearings left. I was met by a bystander and I told him that the bottom bracket sheared off. He responded “I’ve never seen that happen before.”

Anybody know what replacement parts I need for a Stromer ST1? I believe I have a crank puller, not sure about other BB tools.

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J.R.

Well-Known Member
Accelerating away from a green light, something was immediately wrong as I was only standing on my right pedal and my butt was on the top tube. I pulled over and found that my left crank arm was 50 ft back in the middle of the road (not in my spd shoe) and my frame was showing an exposed bottom bracket with a few ball bearings left. I was met by a bystander and I told him that the bottom bracket sheared off. He responded “I’ve never seen that happen before.”

Anybody know what replacement parts I need for a Stromer ST1? I believe I have a crank puller, not sure about other BB tools.

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That's an amazing failure. Looks like you need a BBT-22 to remove the cups.


https://www.parktool.com/product/bottom-bracket-tool-bbt-22

Another good brand is Pedro's.

Pedro's Bottom Bracket Socket - ISIS Compatible One Color, One Size https://www.amazon.com/dp/B003FPXLO4/ref=cm_sw_r_cp_apa_i_gKqrDbKYEB5GC

There are other tools for the variety of BB and plenty of cheap ones on the market as well.

I don't own a Stromer, or know the brand of bottom bracket or drive components they're using. I can't offer a suggestion for a new BB. I suspect it's one of the Shimano BB's. Check the documentation that came with the bike. Most quality bikes have the BB listed, it's a selling point Stromer wouldn't pass up.

Replacement is simple and easy. You could upgrade to a better BB for not much more money.

This should help:

https://www.parktool.com/blog/repair-help/?area[]=47