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Running my Middleburn RS7 cranks on square taper and looking for a new BB. Can't seem to find much available. Anyone got any ideas?
Just got one from CRC.
It seems that the old shimano numbers are no more, I think it's a UN55 that I got. It's the one with metal cups and maybe slightly better seals.
15 quid anyway in a plethora of widths and lengths to suit
What length axle do you need?
We have just had a blast from the past and received some the amazing Race Face Taperlock Ti BB's.
They're square taper with a titanium 107mm axle. Fully rebuildable, light weight and all round lovely!
Let me know if its of interest and I'll let you know how to rder one, costs, etc.
Cheers
Richie
UN54/55 - £14ish, cromo axle, about 300g
reliable. as long lasting as the famed but long-gone UN72, but about 60g heavier.
Royce Ti - £160, £35+ tool required. Best in the world.
Phil wood stainless steel about £75 + £20 for tool. I have one and it's nice, serviceable and adjustable.
Loads of generics between £8 and £15 - mainly heavy and questionable bearings
There's some nice Token ones on eBaybetween £25 and £50 but I have no experience of them.
Another vote for Shimano's UN54, it's not niche, it's not posh but they're cheap and last for ages.
much as Id like to say richie's taperlocks are a treat, be aware that middleburns require a 113mm axle to give a 47.5mm chainline - i.e. standard MTB.
If you're running a singlespeed set up with a spaced sprocket on a cassette freehub then you can move your chainline to 44.5mm to compensate assuming you have chainring/chainstay clearance.
If you have a triple ring geared build, you might find the 44.5mm a bit of a git to work with.
Stoner, any idea on ideal axle length for alfine and middleburn uno crank set-up?
Token Square Taper are lighter than Shimano (219g for 68x113) and are wearing very well.
I have the hollow axle with carbon cannister TK866CM.
Possible to dismantle them to replace the bearings, but not needed to get there yet.
The Token ISIS are light too, but not used any yet.
Interested to read the answer to the Uno with Alfine question.
PaulD
nunu - the Uno chainring on a middleburn is in the "middle" position so with a 113mm BB axle will still give a 47.5mm chainline.
I gather that the Alfine has a 42mm chainline unless you flip the dished sprocket making it 47mm.
So you can either use a 113mm BB and a flipped dished sprocket or a 107mm axle (shorter ones arent very easy to get hold of) and have a bit of a difference between the 42mm Alfine and the resultant chainset chainline of 44.5mm.
Personally Id flip the sprocket and work with 47.5mm. Less risk of having a problem with chainstay clearance as well.
Great thanks Stoner 🙂