IRD Quad QB55 JIS English Thread Sealed Cartridge Bottom Bracket 68 mm Shell

I recommend this product

Eighteen months ago, I bought a Shimano UN300 to replace the original UN5* series BB on my 15 yr old tourer. The UN300 failed after only 18 months so I contacted SJS asking for advice. They recommended IRD and I went for the least expensive model with the steel cups. The cartridge bearings, which are Tange Seiki, are a lot deeper than the Shimano UN300 ones. Hopefully this will have been a 'fit and forget' purchase!?

I recommend this product

Bought the 122mm version and was replacing a shimano BB-UN54 bottom bracket.
I decided steel cups were better in my old steel frame as the threads were less likely to seize than aluminium cups, which you get with the more expensive Quad 75. The weight penalty is insignificant for me.
I measured the asymmetry when fitted and the spindle is about 0.5mm from the frame centreline towards the right (drive) side of the bike, which is unnoticeable.
Bearing o/d looks slightly larger than the previous shimano bearings which, in theory, implies longer life.
Lastly, it's great that SJS cycles stock the IRD brand which specialise in producing high quality parts to keep older models of bicycles on the road.