Cobia BB Compatibility??

[cbd5600]

I want to replace the stock crankset on my '12 Cobia. With the sales going on I can also get into a SRAM Ceramic GMP Bottom bracket.

Question is, will the GXP BB fit my '12 Cobia? The stock BB is internal bearing and the GXP is External. I just want to be sure before I jump on it.

Any help is appreciated.

[shibiwan]

I want to replace the stock crankset on my '12 Cobia. With the sales going on I can also get into a SRAM Ceramic GMP Bottom bracket.

Question is, will the GXP BB fit my '12 Cobia? The stock BB is internal bearing and the GXP is External. I just want to be sure before I jump on it.

Any help is appreciated.

There are two parts to the answer:

Yes, the BB is a standard 68/73mm BB and external bottom brackets like the SRAM GXP, Shimano Hollowtech II, Hope Tech, and Race Face EXI will fit.

Even though the external BB will fit, you will definitely need a new crank. The standard cartridge-style "Powerspline" BB on your bike comes as one unit and the crank spindle is part of the BB. You will need a crankset that is either GXP compatible or Hollowtech II/Raceface compatible (Both the HT-II and RF cranksets come with a 24mm spindle. I'm not sure about the GXP)

In summary: Yes the GXP BB will fit, but you will need a new crankset too.

-S

[cbd5600]

Great Information. Thank you for the quick response.

[eb1888]

The non drive side bearing on a new SLX bottom bracket I installed was very light on grease at installation. Check both and load before using. The plastic cover and seal can carefully be pried off for servicing. I pry around the outside of each with the thin edge not tip of a flexible knife until it starts to come up.

[ChewynMe]

CB I am not sure if you have made a purchase yet, but I too have a 2012 Cobia and just bought the X9 crankset from Jenson for $100 with the GXP BB. LBS (Trek Dealer) said it fits, no problem, and that it was a very good upgrade for the $$$

[cbd5600]

CB I am not sure if you have made a purchase yet, but I too have a 2012 Cobia and just bought the X9 crankset from Jenson for $100 with the GXP BB. LBS (Trek Dealer) said it fits, no problem, and that it was a very good upgrade for the $$$

I picked up the same BB from Jenson as well. Just got here yesterday. I am hoping to get it installed on Tuesday.

[ChewynMe]

I haven't put mine on yet, but please let me know how it goes! Kick some dirt when you are done.

[cbd5600]

I will for sure. I'm trying to figure out ow to get it done faster. It will be interesting to see the weight difference over stock. The new crank and BB came right at 880g.

[ChewynMe]

My bet is not much, unless the howitzer BB included with the S800 weighs a ton. 100-150g?

[cbd5600]

Dropped it off at my LBS today. Should be ready Tuesday. The FD might be an issue with the new crank, but hopefully he can get it to work.

[cbd5600]

Picked my bike up yesterday, but the weather has been terrible so no ride yet. The new crank is actually 38g heavier than the stock one. The bottom bracket however is 288g lighter.

Here it is all installed.

[ChewynMe]

Wow our garage walls look so similar! It looks like you went 1X10? Or is it two but I can't see the inner ring? Bold move BTW choosing the red. I'm jealous.

[ChewynMe]

[QUOTE=cbd5600;9955037]Picked my bike up yesterday, but the weather has been terrible so no ride yet. The new crank is actually 38g heavier than the stock one. The bottom bracket however is 288g

That a net loss of 250g's. not too bad!

[cbd5600]

Wow our garage walls look so similar! It looks like you went 1X10? Or is it two but I can't see the inner ring? Bold move BTW choosing the red. I'm jealous.

Its 2x10 right now. We'll see how it does after a few rides. I never came out of the middle ring with the stock setup and I was always in the middle to upper half of the rear gears. I ordered a 12-26 rear cog that will get me closer to what I had running the middle gear up front and the stock 11-36 in the rear. If that works out well, i'll probably ditch the big ring for a bash guard.

[wmac]

Its 2x10 right now. We'll see how it does after a few rides. I never came out of the middle ring with the stock setup and I was always in the middle to upper half of the rear gears. I ordered a 12-26 rear cog that will get me closer to what I had running the middle gear up front and the stock 11-36 in the rear. If that works out well, i'll probably ditch the big ring for a bash guard.

Whoa, what? You ordered a 12/26? I sort of get it if you're looking to lose weight, but that's cutting your range down quite a bit. You sure you don't want to keep that low gearing for those really big climbs at the end of a really long ride?

[ChewynMe]

[QUOTE=cbd5600;9955037]Picked my bike up yesterday, but the weather has been terrible so no ride yet. The new crank is actually 38g heavier than the stock one. The bottom bracket however is 288g lighter.

Here it is all installed.

---Ok so on my phone only the middle pic showed up, now I see the whole deal. Looks great and I hope it works out as smoothly as you (an by extension I) planned. I will not have tiome to install mine until after Xmas. But I stuck to a 12-32 in the rear, and the 28-39 up front.

Happy Dirt.

[cbd5600]

Whoa, what? You ordered a 12/26? I sort of get it if you're looking to lose weight, but that's cutting your range down quite a bit. You sure you don't want to keep that low gearing for those really big climbs at the end of a really long ride?

The new front gear is a step down from 33t to 28t and will almost offset the step down in the rear. I will be losing a little bit as the ratio will drop from .92/1 to 1.08/1.