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Another creaking bottom bracket - advice sought replacement?!

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contrariousjim 13 Jun 2014
Hi All,
Yet another bottom bracket problem. I have a giant ocr2 of 2004 vintage. It has a truvativ triple 9sp chainset set up, and the bottom bracket is a sealed unit held in place by plastic cups, not these new fangled outboard BB cups.

My BB has not only started creaking, but I took the cranks set off, and you can clearly feel grit or rust or something like it in the BB causing a stop start rotation. I tried to get off the plastic cups, and half destroyed the plastic teeth in the process. There was a huge amount of gritty rust crud around the sealed bottom bracket unit, but the BB itself has some resistance in turning.

Now, I'm not sure what to do. Can I get metal replacement caps and a new sealed BB unit for the same kind of chainset setup I have? I can't find what I need. There seems to be mostly the new type of BB cups for hollowtech etc on the sites I look at.

This also got me looking at the chainset which looks pretty scalloped especially on the 52t chainring. Is there an easy, not too expensive in to this new type of technology?

Any help / advice / suggestions greatly appreciated!
 sleavesley 13 Jun 2014
In reply to contrariousjim:
Is the BB a sealed cartridge square taper?
On an older bike I just took it out and swapped it over for hollow tech as I could. Most new chainsets will come with the BB included.
I'm assuming its a triple nine speed?
Post edited at 10:13
 TobyA 13 Jun 2014
In reply to contrariousjim:

I'm presuming its a square taper one? ie. once you have got the the chain set and other crank off there are tapered square things protruding that the cranks sit on? If so, changing a BB the first time you do it can be a hassle mainly because you need to get the right type of tool to get the cups things out and I've found they can be super stiff. Lots of washing and WD40 or similar helps. Then once you've got the bugger out you need to work out what size it is if you don't have a legible sticker still on it. I ended up buying my first vernier caliper to do this (and of course then having to look up on the internet how you read the thing!) then you have to work out where the measurement is taken from on the BB. Once you've done all that (which I remember taking bloody days and necessitating various trips to the DIY/bike bits store for the tools), then just go on Wiggle or whatever and order the part! Putting a new one in is a piece of pee in comparison! Once you've done it the first time and you have the tools, it's easy to do in the future although invariably future bikes will have a different BB type (my road bike does) making your tools and hard earned knowledge totally redundant.

Good luck and have fun.
 balmybaldwin 13 Jun 2014
In reply to contrariousjim:

your local bike shop will probably have them in stock if its remotely decent, you'll probably be looking at £20-30 for the BB and to have it fitted. No need to change your chainset if you don't want to.
contrariousjim 13 Jun 2014
In reply to sleavesley:
> (In reply to contrariousjim) Is the BB a sealed cartridge square taper?

Yes. It is. I'd never done anything except wash my bike. The crank bolts were loose on both sides. But the crank arms were well wedged onto the square tapers of the BB. It seems to be that the BB is fecked, but there was also an awful lot of crap (rust, greese, grit) around the BB.

> On an older bike I just took it out and swapped it over for hollow tech as I could. Most new chainsets will come with the BB included.
> I'm assuming its a triple nine speed?

Yes it is, and sram triple 9sp, truvativ 52/42/32.

Talking of which I hardly ever use the 32 (usually only when towing the sprog and getting lazy on the hills). Can I replace it with a double, as they seem a bit cheaper if I am changing the crankset with the bb.
contrariousjim 13 Jun 2014
In reply to TobyA:
> (In reply to contrariousjim)
>
> I'm presuming its a square taper one? ie. once you have got the the chain set and other crank off there are tapered square things protruding that the cranks sit on?

Yes.

> If so, changing a BB the first time you do it can be a hassle mainly because you need to get the right type of tool to get the cups things out and I've found they can be super stiff. Lots of washing and WD40 or similar helps. Then once you've got the bugger out you need to work out what size it is if you don't have a legible sticker still on it. I ended up buying my first vernier caliper to do this (and of course then having to look up on the internet how you read the thing!) then you have to work out where the measurement is taken from on the BB. Once you've done all that (which I remember taking bloody days and necessitating various trips to the DIY/bike bits store for the tools), then just go on Wiggle or whatever and order the part! Putting a new one in is a piece of pee in comparison! Once you've done it the first time and you have the tools, it's easy to do in the future although invariably future bikes will have a different BB type (my road bike does) making your tools and hard earned knowledge totally redundant.
>
> Good luck and have fun.

Thanks. The more I learn about and work on my bike myself, the more fun I have! This is my bike...

http://www.bikepedia.com/quickbike/BikeSpecs.aspx?year=2005&brand=Giant...

...albeit with lower specced components, e.g. deraillers, wheels, etc, but that gives the basic information on the BB:

Bottom Bracket Sealed cartridge, 113mm spindle
BB Shell Width 68mm English

I think the tool I have is the right shimano BB tool, but it just shredded the teeth on the plastic cups when I was removing them, but I got the cups off ok. I just don't think it'll be possible to put them back on, so will need the cup bits, but it looks like the come with the sealed BBs?
contrariousjim 13 Jun 2014
In reply to sleavesley:

> On an older bike I just took it out and swapped it over for hollow tech as I could.

But you mean, you swapped over not just the BB, but crankset as well to hollowtech?
 sleavesley 13 Jun 2014
In reply to contrariousjim:
Yes. Just took it out and upgraded the bottom bracket and crankset to hollow tech. Just ordered the English thread. Put it in and the new crankset and away to go.
As above Ribble have something for a reasonable price.
Post edited at 11:59
andreas 13 Jun 2014
In reply to sleavesley:

> Yes. Just took it out and upgraded the bottom bracket and crankset to hollow tech. Just ordered the English thread. Put it in and the new crankset and away to go.

> As above Ribble have something for a reasonable price.

Might need the frame facing too. I went through a couple of hollowtech BB's quite quickly with an old frame.
contrariousjim 13 Jun 2014
In reply to sleavesley et al:

> Yes. Just took it out and upgraded the bottom bracket and crankset to hollow tech. Just ordered the English thread. Put it in and the new crankset and away to go.
> As above Ribble have something for a reasonable price.

Is it possible to switch to a double hollowtech? I have tiagra st-4400 shifters which I believe from the tech docs are double and triple compatible. I have a shimano sora front derailler, and it actually looks more like a double than a triple, but I'm not sure, and its working on my triple. Can I put on a double such as the below, am I likely to need to change the derailler, and will a 10sp chainset work with my 9sp rear set up?
contrariousjim 13 Jun 2014
In reply to andreas:

> Might need the frame facing too. I went through a couple of hollowtech BB's quite quickly with an old frame.

What does frame facing mean? Does that mean getting the thread redone?

Also, same questions I've just put to sleavesley, can I put to you too.. ..I seam to remember you helped a while ago with useful advice on my wife's look bike....
 Oujmik 13 Jun 2014
In reply to contrariousjim:

Yes to 10 speed chainset with 9-speed. Unless I am mistaken the only difference is that the outer width of the chain is less to allow it to fit between the sprockets of a 10sp cassette, the internal width is the same so it will run on the same chainset.

Not sure about a double with triple levers, I expect it could be made to work, but nor sure how well it would work.
andreas 13 Jun 2014
In reply to contrariousjim:

Frame facing is getting the BB shell perfectly parallel so that once the cups are in the axle (a 1"ish tube running 90 degree from the crank) sits properly in them. If the shell's a bit out then the bearings don't get a uniform force on them and wear out quicker. I guess they do this with a file and a template of sorts but I've never seen it done.

Ten speed chainrings are fine with nine speed chains but not the other way round. Front derailler should be fine, not sure about the shifter, it should work but might not be perfect. My front shifter is a double and has four positions I can hold the mech in (two per cog), I think a triple just has three positions (two of which you'd use) so you might find you get a fair bit of chain rub.

It could be a fairly expensive upgrade and much more expensive than just replacing the old BB, which, annoyingly, will probably last twice as long as a same priced hollowtech one. Personally I'd recommend though as three speed chainsets are annoying and unnecessary, the hollowtech is lighter and stiffer plus you get more options like your gear set up and crank length (look into this before buying, your ideal crank length is dependant on your height and legs the same way a frame is). From my experiences I'd expect to have to put a more expensive BB in fairly soon too, I use hope ones now.
 sleavesley 13 Jun 2014
In reply to contrariousjim:

http://techdocs.shimano.com/media/techdocs/content/cycle/SI/TIAGRA/ST-4400/...

Your shifters are both double and triple compatible, although to work with a double or compact you should have a double front derailleur to allow it to work across the range as the triple and double front derailleurs have different chain lines and range of chain stay angle.
A front derailleur will be around £15 unless purchase cheaper off eBay.

Facing IF needed would be done at LBS as the tools are quite expensive. I would try it without to start off with - if you have any problems message me and I'll sort you out a hollow tech BB for postage cost only.
 malk 13 Jun 2014
In reply to andreas: i need a new triple as the middle ring is worn out (big ring is too big for loads)
i'm thinking of the deore 48/36/26 9 speed, but that means changing to hollowtech. or maybe i should stick with square taper (eg acera)? cheaper and more durable?
andreas 13 Jun 2014
In reply to malk:

Yeah it's a question of performance vs cost really, I use hollowtech because I can have much more choice with gear ratios on my mountain bike and can fit 180mm crankarms on the road bike, plus I like the weight reduction and reduced flex. I do use 70 quid hope BB's though.
 Oujmik 13 Jun 2014
In reply to malk:

You can just replace the chainring instead of replacing the whole thing. I prefer hollwtech as they are generally cheaper and much easier to work with but they do tend to wear a bit faster than some designs.

Also, just to be clear you are talking mountain bike groupsets wheras the OP was about road?
contrariousjim 13 Jun 2014
In reply to Oujmik:
> (In reply to malk)
>
> You can just replace the chainring instead of replacing the whole thing. I prefer hollwtech as they are generally cheaper and much easier to work with but they do tend to wear a bit faster than some designs.
>
> Also, just to be clear you are talking mountain bike groupsets wheras the OP was about road?

OP was definitely about road!
contrariousjim 13 Jun 2014
In reply to andreas and sleavesley:

Thanks for your advice. I think I'll see if I can get a straight replacement BB from my LBS.. ..the shimano UN55 (68x113mm) looks like the right one for around £20, avoiding the plastic cuffs on the cheaper ones. Seems strange that for 2.5x that price you're into new double crankset hollowtech II territory... ..if I can get it working. Hmm.
 malk 13 Jun 2014
In reply to Oujmik:
> You can just replace the chainring instead of replacing the whole thing. I prefer hollwtech as they are generally cheaper and much easier to work with but they do tend to wear a bit faster than some designs.

> Also, just to be clear you are talking mountain bike groupsets wheras the OP was about road?

dunno about cheaper but i've heard hollowtech is 'stiffer' so less likely to get chain rub on the FD as i currently do with my steel frame..?
i'm talking touring, so mtb groupsets prob more suitable? never use the 52 ring so might as well replace the whole crankset..

Post edited at 16:03
 malk 13 Jun 2014
In reply to contrariousjim:

> OP was definitely about road!

what does it matter?
contrariousjim 13 Jun 2014
In reply to malk:

No idea.. ..ask the guy who asked you the Q.

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