Bottom Bracket question

[Cubist]

There's a distinct grumble from the BB on my Cube Peloton Race as I push the pedal by hand from 3 0'clock to about 7 O'Clock (ie power stroke on my right pedal). This has translated to a distinct creak when under power especially climbing. No doubt that the BB is shot, so I need to replace it. The BB cups say it's a Shimano 5700, then "700" so I'm thinking it's a 70mm one. Can anyone confirm that for me?

Next. There are some deals about on 5700 BBs, with the 68mm ones being far far cheaper. I take it it isn't like MTB BBs where you can spacer a 72mm BB to fit a 68?

Next question..... Are Ultegra compatible with my 105 5750 chainset? If they are, the wonders of Internet shopping tells me I can pick up a Ultegra 70mm for about a fiver cheaper than a 105.

 

[uclown2002]

The 5700 is a model number and doesn't indicate a 700 mm thread. I would have though it was the 68mm English thread but can not confirm.

http://www.chainreactioncycles.com/shimano-5700-105-bottom-bracket/rp-prod50450


It is a HT2 type BB which the ultegra is also so should be fine with correct thread.