How do I get the bottom bracket out?

I have a Strida LT. Second-hand, so I don’t know the full history.

I’m trying to replace the bottom bracket. I’ve removed the kickstand, left crank, and the 60mm lockring:


I’m led to believe that the asymmetric bottom bracket should now be somewhat loose (for adjusting the belt tension). It is not. In fact, I put a long M8 screw in the bottom bracket and applied a cheater bar, and this effort bent the screw. The bottom bracket did not rotate at all.

A generous amount of WD40 sprayed into the crevices of the BB has not helped.

I also tried propping up the BB on a little pvc pipe (to avoid putting pressure on the crank) and hit the bottom tube bracket assembly with a rubber mallet:


Did not budge at all either.

Any ideas? I have in my toolkit a hot air gun, but I have doubts on reaching the temperature differentials required for what seems to be an unintentional press fit.

Bonus dog pic:


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Ok, first many thanks for the bonus pic, your friend looks really sweet

You have a very rare (and odd) problem here…

Did you try that in both directions (forward and backward)?

I mean the first thing you must do is to move the excenter - to release belt tension.

Could you please send the image below - in full size - to my email account?

Link to full size:

(imgur trick: you can suffix any filename with “s”, “m”, “l”, “h” to automatically resize images)

Yes, I tried the cheater bar in both directions. I tried tapping the screw with a mallet also. No dice. I had the understanding also that the first step is to release the tension by rotating the asymmetric BB, but it won’t turn and it won’t come out.

I ping’d the FLBS distributing Stridas here and they suggested bringing it in for them to take a look.

Many thanks for teaching the imgur trick!

I mean the bottom bracket looks really good, no sign of slipping at all.
Could it be that the previous owner glued the excenter into the bottom bracket housing?
At the left (forward) part of the black excenter, one can see a shiny line, close to the lower edge of the housing’s slot.
That could be glue - or is it grease (or WD40 remains)?

I guess the belt is under high tension.
You could derail it with a screwdriver, too - but there is a big risk that you destroy the belt this way.

Will you accept the offer?
If yes, please don’t forget to post the result.

Do you like anticlimaxes? I sure do!

We tried the cheater bar again at the FLBS, with no more success than previously:


The answer was to remove the right crank and beltring (without detensioning the belt - there was no way to do so anyway). This allowed for a firm grip on the assembly from the right side. Then using the PVC pipe as a pusher, the FLBS used the world’s biggest rubber mallet and the fury of a thousand suns to just hammer the BB out. Took like a dozen blows.

(if anyone’s shopping for the PVC pusher, a DN25/G1" connector works wonderfully)

Upon inspection there is nothing wrong with the bottom bracket or the shell. There is no glue residue. The replacement aluminium bottom bracket just popped right in without a pusher also, so I guess it was just arbitrary variation in the plastic casting.

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Yes me too - here’s the anticlimax to Strida - 36" wheels instead of 18" :laughing:

Hold on, wait a second; we have Sunday and in your area it will be around 8 in the evening, right?
And your LBS was open??? :open_mouth:

:laughing: :laughing: …wow, that was very well said!

Thank you, great to read that your problem is solved :wink:

Indeed, the Strida distributor here has “mall hours”… 9pm every day, seven days a week!

On the other hand, they’ve told me that the Stridas now sell so poorly here relative to the Brompton invasion that they’ve moved on to post-patent-expiry trifold knockoffs. They’ve removed all the display Stridas too. It’s sad… luckily, they’re still great about support.

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Amazing…you must imagine; here, in my “cosmopolitan city” :laughing: Vienna you may find a tube vending machine (if you’re lucky) - but that is it on a Sunday.

Yes I hear that from everywhere, just what is the reason for this sad situation?
I’d say mainly the lack of advertising, no real development and poor customer support by Ming cycle themselves.