After much thought n reading up on threads I have decided to go with a new middleburn UNO crankset for my SS build. I havnt used square taper for a long time as my last few cranks have been X- type. Is this a problem as far as reliability and weight when looking for a BB . Or is it better to go Isis version though I’ve heard a few problems with that type of bb. The rx-8 type UNO looks nice but is alot more ££ so its square taper or Isis ?
Anyone who could help put my mind at a ease before I purchase ?cheers

Never heard of x-type. Square taper is as reliable as it gets. I guess they weigh more but who cares about that.

X-Type = RaceFace’s version of hollowtech II

I’d never use Isis again , very short bb life not as poor as pf30 though

Stick with the taper either shimano un 55 or if you have the money Phil wood or Royce

Get the x type. Worth the extra dosh. Isis is rubbish and st bb that are good quality are getting scarce. Be aware that the xtype uses a different chainring….

So for a single speed frame being my onone inbread would the middleburn rs8 x-type crank work as well as the rs7 or rs8 square taper .as far as alignment etc .its nearly £100 more for the xtype UNO over the taper so still not sure i can justify it .rs-7 with a coated UNO ring is £138 where as the rs8 UNO xtype Is £220

If you get either isis or sq taper, you won’t be able to fit them on a BB92 type bottom bracket if you ever change your frame. However if you get the x-type you will be able to fit them to everything.

I had ISIS on my SS before and sometimes I had to change the BB after 4 weeks! I now have the Uno crank set with a square taper BB. It’s had a few years use now without any problems. I just stick a Shimano number in there and it holds for a few years. If you can stretch to the external bearing version then fine it’s lighter but if that’s not an issue the square taper is just as good.

Cheers guys ,I’m only going to use the crank on this ss bike so not worried about fitting it to other frames but I guess I wAnted to try and keep the weight down so didnt know if the light weight square taper bb’s are at a price that would bring the complete kit to about the same as a x type set up .

HAve a 123 mm sq taper Royce bb lying around somewhere if you wanted. I use the sq t on a couple of bikes and they work really well. The bb’s are smoothera nd more long lived that current external HT.

Trapper and a Phil bb, should be cheaper than the x-type, and the Phil wood will last ages and they will still be making them for a long time.

Messaged u mate ref bb you have cheers

Oh yeh my bb is 68 mm will yours work?