Flipping Bottom brackets!

zedders

Am still sorting the old bike out ready for the winter. I have ordered a few bits including some token aero bars for the turbo, and a new polar HRM/computer with help from the site already, but now I need a new bottom bracket.

I have a 2007 bike with 8 speed Sora (as listed below with spec including an FSA BB), which I’ve had for a couple of years now. I want to change the BB (sealed cartridge?) which has done about 2000mile, as I think its knackered? (grinding noise & not running very smoothly).
http://www.bianchi.com/en/products2007/Road_Y7B49.aspx

Knowing jack about BB’s, and not wanting to buy the wrong size etc, any chance someone could point me in the right direction? I’ve seen BB’s from Shimano but they don’t seem to do a Sora one? And likewise with FSA . I honestly don’t know which ones are compatible with my bike? I really don’t know which one to get, and I don’t even know if mine has a Italian or English thread? :oops: One of my mates said get a Shim105 Octalink one – but I don’t know if he’s right? :? There seems to be hundreds on the market! :shock:

If I could get one a bit better than the standard one fitted by Bianchi, that would be good, but I don’t want to spend a fortune. I’ve seen BB from £10 to £150+. So I’m hoping I could get something reasonable for around 30 quid? Could someone help or advise pls?
Cheers

Zedders.

System_1

Your mate's wrong in suggesting an Octalink BB. Looking at the spec it's a square taper crank and BB so you'll need to replace it with a square taper BB unless you fancy changing the cranks too.

The spec on your link says it's a JIS 68-110mm.

JIS is one of the two standards of square taper, the other being ISO. Shimano, FSA etc are all JIS taper with Campag being ISO. You'll need to stick to what you have or there will be trouble with how the cranks will fit to the BB.

The 68 measurement is the width of the bottom bracket shell. It suggests to me it's English thread as Italian thread BB's tend to have a 70mm shell width.

The 110mm measurement is the axle length. This is what will dictate your chainline. 1 or 2 mm either way won't make too much of a difference but stick to 110mm if you can.

There are loads of Shimano 68mm x 110mm BB's around. Chain Reaction have a UN54 for under £12. Nothing fancy about them but they are tough and reliable. I've had one on the fixed gear that's done over 5000 miles now and is still running well.

zedders

System:
Thanks for explaining that. I knew all the numbers ment something! I'll give my cycling bud a kick up the backside. He probably wanted me to order a Octalink one so he could con it off me on the cheap as he has a 105 gruppo. (He's like that!)

The UN54 you mention. I won't disagree if you say it's tough & reliable, but would it be worth spending a bit more on a so called ''better'' one? Or do you think I'll just be wasting my money trying to upgrade so to speak?

crankycrank

Agree with everything System said. I would recommend posting a pic or checking with your LBS though because occaisionally what is listed in the specs is different than what is delivered on your bike. You may have a different crank or ??. The UN-54 would certainly be a good quality, durable replacement but also a Shimano model UN-72 would be better if you can find one since I don't think they are made anymore but some shops may have some NOS lying around.

System_1

The FSA BB you're replacing is a cheap bit of kit (I had one on a bike, rebranded as RPM and it lasted about 600 miles) so the UN54 is already an upgrade IMO. Shimano do a UN72/73 as well, which is better quality at least with regards to weight, but good luck finding one. They seem to be getting scarce.

I'm not sure what else there is out there in that kind of middle ground. Royce, Phil Wood, White Industries etc might be a bit overkill. Personally I wouldn't spend more than £30 on a BB if it's going in a fairly middle range bike. They don't really add to performance so you just need something that won't break and will last a decent amount of time.

System_1

Oh, and one thing worth mentioning is that it's worth keeping a hold of the metal non-driveside cup off the FSA BB before you throw it in the bin. Shimano use a plastic cup on the non-driveside and I've had one crack once when I got a bit ham-fisted with the tool. I use the metal cup from my old FSA/RPM with my Shimano BB to save future grief. It's always worth having this kind of thing in the spares box anyway.