What will replace the quality of the discontinued Shimano BB-UN55?

[Jameshow]

OK, I've installed a Shimano UN300 BB in my bike today, lets see how long it lasts. I've put an excessive amount of grease inside and outside of the BB, which I'll do every year, it's not too tight, so not to overload the bearings.

Shimano UN300 BB on offer for £11
https://www.sprocketscycles.com/products/shimano-bb-un300-bottom-bracket-british-thread?currency=GBP

Give us an update on Monday!

 

[Ajax Bay]

Shimano UN26 68x113 Bottom Bracket £5.49 at Ribble.
(Yes, the type with the rubbish plastic cup, but you can use your old metal BB cup.)
https://www.ribblecycles.co.uk/shimano-bb-un26-square-taper-bottom-bracket-silver-113x68/

OK, I've installed a Shimano UN300 BB in my bike today, lets see how long it lasts. I've put an excessive amount of grease inside and outside of the BB, which I'll do every year, it's not too tight, so not to overload the bearings.
Shimano UN300 BB on offer for £11
https://www.sprocketscycles.com/products/shimano-bb-un300-bottom-bracket-british-thread?currency=GBP

I very much like your idea of using a UN-26 with a previously used metal left hand screw-in end. I believe (on no evidence other than one that lasted at least 25,000km) it's the same bearing set as a UN-55 with the LH plastic end (which disintegrated when I tried to remove it, btw, LBS no prob) the only difference.

 

[GuyBoden]

Give us an update on Monday!

Unbelievably, the Shimano UN300 BB didn't disintegrate during the ride today.

 

[Ajax Bay]

How's the UN-300 going @GuyBoden ? How many thousand kms?

 

[GuyBoden]

How's the UN-300 going @GuyBoden ? How many thousand kms?

I've designed the ultimate maintainable bottom bracket from available parts, it's this:

https://www.cyclechat.net/threads/t...bearing-square-tapered-bottom-bracket.293687/

 

[fossyant]

How's the UN-300 going @GuyBoden ? How many thousand kms?

Over 18 months on mine of commuting all weathers. It's still fine. Picked up a spare cheap from Wiggle a few weeks back.

 

[Ajax Bay]

Looking at my as yet uninstalled UN-300, it seems there's an extra part seal on both bearings.