Replacing bottom bracket on my Giant Defy 2

[ColinC]

Hey guys,

I've browsed the web and this forum a good bit regarding bottom brackets, but I'm still a little bit confused about the difference between a press-fit bottom bracket and a standard one.

Basically, the FSA BB in my Defy 2 is on the way out, and I want to replace it. I was frothing at the mouth reading about Chris King BB, so I was about to go an order one of these (and get my local bike man to install it):
http://www.chainreactioncycles.com/us/en/chris-king-bottom-bracket-road/rp-prod33554
(or possibly the Shimano Dura Ace 7900 BB).

I wasn't sure about the size, so I checked the FSA in my Defy 2, and it shows the figures: 1.37x24. I had no idea what this meant, so I googled it and found this helpful page: http://sheldonbrown.com/bbsize.html
According to Sheldon, I have a bottom-bracket with British threading, therefore I should be able to order a 68mm British standard BB.

But then I started reading all this stuff about press-fit and non-press fit... and I got confused.

So my simple question is;
Can I order the Dura Ace 7900 (British std) or CK (British std) and get my local bike man to install it in place of the FSA Mega Exo press fit?
[I'm quietly hoping you guys will tell me yes, because from what I hear the press-fit BBs are pretty troublesome]

Thanks for any help on this. My BB is knocking away so time is running out

 

[RecordAceFromNew]

I wasn't sure about the size, so I checked the FSA in my Defy 2, and it shows the figures: 1.37x24. I had no idea what this meant, so I googled it and found this helpful page: http://sheldonbrown.com/bbsize.html
....
Can I order the Dura Ace 7900 (British std) or CK (British std) and get my local bike man to install it in place of the FSA Mega Exo press fit?

I am not sure if you have provided definitive info as to exactly what bb shell your frame has (which is not necessarily the same as what bb is installed, because various adapters exist for press fit shells, of which Sheldon's page you referred to doesn't cover). To add to potential confusion it appears the Defy 2 can come with press fit or not...

To avoid mistake it is worth checking. I believe it is likely either traditional (with 68mm shell) or what they call BB86 on your bike. I would suggest you measure the bb shell on the frame. The bottom of the page here provides some useful info.

Whether the King bb in your CRC link suits your chainset or otherwise would depend on what chainset you have. That is designed for chainsets with 24mm stepped spindle on a traditional threaded (i.e. not press fit) bb shell frame.

 

[PeteXXX]

Is it the same as my Defy2 and does the pic of mine help for identification?

 

[ColinC]

Hey guys,thanks for the helpful responses.

My bike is the Defy 2 from 2012: http://www.giant-bicycles.com/en-gb/bikes/model/defy.2/9317/49822/#specifications

CassetteShimano Tiagra 12x30
ChainShimano Tiagra
CranksetFSA Omega, 34/50
Bottom BracketFSA MegaExo

I will go out and take a photo of my BB asap. Stay tuned...

 

[ColinC]

You just need a standard Tiagra BB (English 68mm ) -which is probably what you have on at the moment.

I definitely don't have a Tiagra BB on - it's an FSA MegaExo. Here is a photo:

 

[Mo1959]

I definitely don't have a Tiagra BB on - it's an FSA MegaExo. Here is a photo:

Maybe this one?

http://www.ebay.co.uk/itm/FSA-BB-40...sure_cycling_bikeparts_SR&hash=item53fe08e7da

 

[accountantpete]

Sorry - I was getting confused with the pic!

Please ignore my comments.

 

[ColinC]

http://www.ebay.co.uk/itm/FSA-BB-40...sure_cycling_bikeparts_SR&hash=item53fe08e7da[/quote]

Maybe this one?

I think it's a MTB one. But I've definitely decided I don't want another FSA MegaExo! They are getting terrible reviews online, and everyone recommends Dura Ace or Chris King.

So based on my photos - does anyone know if I can get the DuraAce or CK?

 

[accountantpete]

up to speed now...

Try this page - bottom is most relevant. It suggests that you can (I'd still go for the Tiagra though!)

http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=102563

http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=102563

 

[RecordAceFromNew]

I've definitely decided I don't want another FSA MegaExo! They are getting terrible reviews online, and everyone recommends Dura Ace or Chris King.

So based on my photos - does anyone know if I can get the DuraAce or CK?

Can't see your photo for some reason. If your bb is an outboard one that looks like the one Petexxx has and the frame has a 68mm shell and your chainset is a FSA Omega then the King bb in your crc link is unsuitable - it says it is for stepped 24mm spindle (i.e. sram/truvativ chainset). However all 68mm road HT2 ones should be compatible and this should also be fine, and a bargain (well for a King bb anyway) for £82.

 

[Deleted member 22722]

ColinC,

I don't believe any of the BB's that have been recommended to you will work with your frame as you require a press fit BB rather than an external BB.

Take a look at one of my previous posts http://www.cyclechat.net/threads/re...from-a-giant-defy-1-2012.134408/#post-2531111 as I went through the same learning curve as you. Initially I made the mistake and bought a Chris King external BB. Had to send it back as it was incompatible with by Defy 1 frame (which is the same as yours).

 

[ColinC]

Hi guys,

To clear up the confusion; please see the following photos of my bike:

https://plus.google.com/100478314515069116077/posts/ibksiLV19rt

From googling photos of "press fit" BBs, I have a feeling mine is actually a regular one, non press-fit.

 

[the_mikey]

That's a regular external bottom bracket. You could replace the BB and chainset with Shimano Hollowtech2 parts if you wanted.

 

[ColinC]

That's a regular external bottom bracket. You could replace the BB and chainset with Shimano Hollowtech2 parts if you wanted.

Thanks for the advice mate. And is it true that I could also replace the BB alone with the Dura Ace: http://www.chainreactioncycles.com/us/en/shimano-7900-dura-ace-bottom-bracket/rp-prod28439

 

[Dmcd33]

I've got the exact same bike as you and my BB started creaking and I could feel the bearings weren't right. I was told by my bike shop (Really good Giant suppliers in Clapham) that I could only replace my BB with the mega Exo (which I got after calling various local bike shops). I was also looking at other BB's, as the reviews and my own experience of it (mega Exo) wasn't that good. I had only completed about 6000 miles all in all weathers.

One bit of advice I was given was that the pressure washers that are used for cleaning the bike can push the grease in the bottom bracket out, which leads to further wear.

- Have you tried opening it up (you need the tools) and tried cleaning and re-greasing it? If not a new one is likely to set you back £40-50.