Truvativ bottom bracket replacement for GT

paulneenan76

Hello - my brother has a GT Agressor XC2. I believe it's the black and white one from 2009, and it's in need of a bottom bracket. He took it back to halfords who said that because its the spline truvativ 68/118 for the truvativ cranks, it is difficult to source and maybe he should just get a new crankset (been waiting for this replacement for 1week so far).

Are they talking utter tosh (it is halfords) or is it a worthwhile move to change the chainset with a more standardised BB?

My LBS reckons changing a bottom bracket can take 1-3 hours depending on how stuck it is etc, which equates to £40-120 . Is this something that's easily done with correct tools but no bike maintenance stand?

He's missed 2 of our group rides already, one of which was to Forest of Dean.

Thanks in advance

Chunkers1980

Utter crap

cooldad

Sounds like the right ones - Halfords and Ebay.
http://www.halfords.com/webapp/wcs/stor ... yId_210159

http://www.ebay.co.uk/sch/i.html?_nkw=68+118+isis

Should take half an hour or so.

nicklouse

read Parktools.

paulneenan76

Thanks everyone. I'm confused why halfords would tell him it's not going to be in stock until Friday when it's says its in stock in his local store and 2 other stores in the vicinity? And they said its £30+

Could it be the truvativ chainset takes a different size or type 68/118 splined BB?

Thanks again.

chez_m356

paulneenan76 wrote:

Thanks everyone. I'm confused why halfords would tell him it's not going to be in stock until Friday when it's says its in stock in his local store and 2 other stores in the vicinity? And they said its £30+

Could it be the truvativ chainset takes a different size or type 68/118 splined BB?

Thanks again.

sounds like its a case of a numpty not knowing what he's talking about, your brother wants to tell them to look on there own website

cooldad

Isis is the Truvativ splined standard.

paulneenan76

Thanks all. I'll break the news to him in the morning and suggest he goes and orders the part from halfords for store collection

Halfords biggest issue is bike repairs by unqualified kids and middle aged tinkerers handing out poor advice and terrible service. Then again, sometimes your LBS don't make it easy and can often be a bit patronising and overpriced! I suppose learning to do it yourself is best if you the time.

supersonic

cooldad wrote:

Isis is the Truvativ splined standard.

No, it isn't. ISIS is an old International Standard, that many used, including Truvativ. Truvativ also used PowerSpline, which is a different interface. So need to find out what cranks and BB are on there.

chez_m356

supersonic wrote:

cooldad wrote:

Isis is the Truvativ splined standard.

No, it isn't. ISIS is an old International Standard, that many used, including Truvativ. Truvativ also used PowerSpline, which is a different interface. So need to find out what cranks and BB are on there.

truvativ isoflow if standard http://www.thebikelist.co.uk/gt/gt-aggressor-xc-2-2009 so it would be using one of these http://www.chainreactioncycles.com/Mode ... elID=21496 powerspline, that would be why they were quoting him £30 then

paulneenan76

Ok so is this option going to fit? http://www.halfords.com/webapp/wcs/stor ... yId_210159

I'm thinking that they want to sell him the Truvativ version which is more expensive at £30?

nicklouse

no that is ISIS not Powerspline.

http://www.google.co.uk/#hl=en&sclient= ... 89&bih=940

from 10 quid.

chez_m356

nicklouse wrote:

no that is ISIS not Powerspline.

http://www.google.co.uk/#hl=en&sclient= ... 89&bih=940

from 10 quid.

like i posted previously, CRC is your best bet, no silly postage costs http://www.chainreactioncycles.com/Mode ... elID=21496

paulneenan76

Thanks everyone. I'll update him. When the whole lot goes, I'll recommend he change to a Deore or SLX. Many thanks again.

nicklouse

paulneenan76 wrote:

Thanks everyone. I'll update him. When the whole lot goes, I'll recommend he change to a Deore or SLX. Many thanks again.

he will need to get his BB faced then.

paulneenan76

Faced?
Is that needed just for a change to shimano or would it still be needed for a different Truvativ set or Suntour etc?

nicklouse

for any external bearing set up.

again see Parktools.