Bottom Bracket

[Toback]

ATM my bike has on it a "Bottom Bracket Shimano UN26 " and as im replacing the Crankset Shimano M391, 26-36-48T with a Shimano XT M771 Triple 9 Speed Chainset, can you please tell me what Bottom Bracket I will need as I would allso like to upgrade it....... will copy bikes details underneath how it is at present. thankyou heaps
PS: bought chainset, Derailleur's from wiggle and shifters from c r c, brakes from eBay, well Ive ordered and paid for parts, but waiting.




Giant Cypress LX Specifications:

Sizes S,
Colour Dark Blue
Frame ALUXX grade aluminium
Fork SR Suntour NEX, hydraulic lock-out, 63mm travel
Handlebar Giant alloy, high rise, 25.4mm
Stem Giant alloy, adjustable
Seat Post Alloy suspension, 30.9mm
Saddle Giant Comfort Groove Plus
Shifters Shimano EF-65, 27sp * changing Shimano XT M770 9 Speed Trigger Shifters
Front Derailleur Shimano Acera, 31.8mm *changing Shimano XT M771 Front Derailleur
Rear Derailleur Shimano Acera *changing Shimano XT M771 9 Speed Rear Derailleur
Brakes Alloy V-brakes *changing Shimano Deore Rim V-Brake Set XT BR-T780 M780 Front & Rear
Brake Levers Shimano *changing XT BL-M770 Levers
Cassette SRAM PG950, 11-34T, 9sp
Chain KMC X9
Crankset Shimano M391, 26-36-48T *changing to Shimano XT M771 Triple 9 Speed Chainset
Bottom Bracket Shimano UN26
Rims Giant alloy, double wall
Hubs Giant alloy cassette, 32H
Spokes Stainless steel, 14g
Tyres Giant P-X3, multi surface, 700 x 38c
Extra Kickstand

[KGB]

The un26 is a square taper bb for a traditional 3 piece crank. The new xt one is a Hollowtech model where the bb axle is permanently attached to the drive side crank.
Hence you don't need a traditional bb, it's basically just a pair of cups with bearings.

http://www.google.com.au/search?btnG=&c ... 0bb%20cups" onclick="window.open(this.href);return false;

[KGB]

Search for "hollowtech external bb cups". There will be one that matches the xt cranks but there are several that will fit.

[Toback]

Thanks KGB, this should be ok Hey?

Shimano XT/SLX M770/M660 Bottom Bracket Cup Set

[Duck!]

The M771 crank will come with the necessary bottom bracket.