Hi.

I have some movement in the bottom bracket of my stock setup meta 55.

The non driveside bolt is torqued to spec.

There's a knocking coming from the bottom bracket when pedalling and there's movement apparent when applying lateral pressure through the cranks, by hand.

Question is, is it goosed? The chainset seems OK and shifts sweetly enough, so perhaps an "upgraded" bottom bracket is the answer (don't even know if this is possible with GXP)?

Reluctant to replace with X,Y or Z flashiest/ latest thing as I have an imminent roadie commitment.

This is 3mths weekend use, btw…

Same just happened to mine also on meta 55 but its 2 years old of weekend use. Probably BB gone but im just going to upgrade to an SLX.

From what I understand, if I want to keep the chainset, I have to replace with a GXP bottom bracket?

What are the options for a replacement, low butter content, bottom bracket that is compatible with my Firex chainset?

Yes, it sounds like the bearings are gone in the BB. Standard replacement is about £20 on CRC, hope £60 + £9 for converters.

Personally I'd spend a bit more and get a new (lighter) chainset.

Nobody makes worse bearings than Truvativ.
Even though the GXP is unique to Truvativ: you can just replace the bearings or get a better complete BB.

The shim/ reducer/ adapter that you already have in the GXP BB can be reused, have a look at : steps 8,9,10 etc you do not need the fancy tools.
http://www.enduroforkseals.com/sitebuildercontent/sitebuilderfiles/truvativ_gxp_by_rwc_f.pdf

http://www.hopegb.com/page_mep_force_57.html

Anybody konw if this is an Italian or ISO thread on these bikes?

I have just stripped mine, too. (Truvative Stylo on a Meta 55) Mine has only done 30-40 hrs and it had loads of play in it before I took it off and it was grumbling like hell.

If you read the MBR customer reviews they are not good. lots of experiences like this banded about. Personally I am getting a Shim crankset to replace it all with.

if you just want the cups, they are on CRC but may not last very long.

Yeah, I kind of got that impression. If I replaced the whole chainset I'd want XT or Deus or such like. Trouble is I need a road bike for triathlon commitments and can't spare the wonga.

Do they only make 1 spec of bracket?

Think so. Choices are the GXP one for 20 quid ish (there was one on ebay mind), a bloody expensive ceramic one, a hope + shims or the Enduro

way I thought it out was I can get an SLX double + bash + BB for £89. May even get a few quid back for my Truvative double/ bash setup. I cant afford 89 quid really but dont want to throw 20 quid away on a BB made of cheese either.

I have a bit of time..my Meta is under a Warranty claim (cracks) For the record, Madison have been Fantastic to deal with.