Shimano XT-SLX-Zee Bottom Bracket – £16.99 on CRC, is it worth it over the £9.99 Deore BB51 or is it a false economy?

Yes

I’d say so. I had a Deore one that lasted four wet rides no bs. My XT ones have always lasted really well.

My last Saint one is 18 months old and had only be swapped out because I didn’t want gold cups any more!

Yep, Deore lasts alright in normal conditions and poorly in un-normal conditions (I killed one in a day once) but at best the difference in lifespan’s pretty much the same as the difference in price.

first deore BB lasted 10 months, died due to jet wash, XT one so far lasted 15 months, TOP hat seals are the only thing different! bearings are the same, just smaller gap for the dirt to get thru

I don’t think that’s right- I knocked dents in the bearing race of my deore in a day of downhill, I’m old enough to remember when indexing was new and exciting but it’s not really a good thing in a bottom bracket 😉 Never had that with the higher quality ones.

lol, you may be right, but thats the only visual difference people have reported, and having both in my hands, only thing that stands out, not sure of the xtr version….

Ta for the advice. Went for a BB70, £18 on eBay.

Or go the whole hog and get an XTR from Rose bikes which cost about £21 including postage. Mine has lasted 5-6 times the life of the last Deore and shows no sign of giving up anytime soon

I’m pretty sure the the main difference is stainless steel bearings vs mild steel, which gives you the extra life difference between the two imo.