Major BB confusion - Felt F1

jaron09james

Morning, my first post so thanks for having me and thanks in advance...

Hours I've spent reading about BB's. I've built up two bikes (albeit GXP) and can't figure out my conundrum. Any concrete advise much appreciated.

I have a brand new unbuilt 2013 Felt F1 frameset. My problem is figuring out the BB. The Felt archive websites have it down as a BB30, I've done the measurements and all good. When they sold it as a complete bike (you could buy the frameset also) it had a DA chainset on a FSA BB30 w/ 24mm spindle reducers.

Plan A. I originally wanted to build it up with a Praxis chainset and their M30 BB. Not happening as they say "the M30 won't fit the frame due to the non removable carbon shell insert" and the Praxis chain sets only work with their own BB. It's not a smooth shell, it has a 'shoulder'.

Plan B. My older bike was a Sram Force / Red build. I could do with a new chainset so thinking Red Exorgram BB30. But, which BB30 do I use? I'm not understanding the difference between what I think to be a regular bottom bracket (goes right through the frame shell), then there's bottom bracket that are just bearings, the bottom brackets that have the retainer clip (my frame does not have the groves to hold them) and now a Sram BB30 PF BB. Eh - BB30 PF?

Plan C. Rotor.

Even been to my local bike shop and they were useless which was unusual. I'm not sure if it's me or just an unusual frameset up which I doubt as it was pro level in 2014.

I've spoken to Felt and they keep saying your BB depends on you cranks and I get that, but I'm having to start with the BB and work that way.

Any thoughts hugely appreciated....

thepainandsuffering

I have a Z1 from 2013 which has the same BB shell as you describe. I can't help with the Praxis option other than you are right that the sholder prevents their BB from fitting.

However any loose BB30 brearings will fit the shell, you just dont need to use the circlips, the sholder does the job for you.I found this type of bearing set up poor with a Sram BB30 chainset on my bike. A set of bearings would usually last only 1500-2000 miles or so before the drive side was shot and needed replacing. You may have better luck though.

I now have a shamino crankset on my bike and use one of these: https://www.sjscycles.co.uk/bottom-brac ... oad-68-mm/ It fits and works well so far. Hope this helps a little. N

sungod

with a bb30 shell you have three broad options for bb...

simple bb30, if the shell is within correct tolerance and doesn't deform under load it should be fine, but poor shell may mean things creak

pressfit adaptor to a different bb standard, such as sram gxp, or shimano, but if the shell is poor this will be just as susceptible to creaking

'clamping' adaptor to a different standard, this type has two halves that thread together (similar in basic principle to the praxis, though theirs don't actually clamp axially, they rely on a collet one end but it's still pressfit the other end), but whether any given adaptor will fit depends on the exact dimensions inside the bb shell, that 'step' is the issue, you'd need to do a lot of research to see if any would fit

i'd go with bb30, grease well (with marine grease) when pressing in, pay attention to maintenance especially if you ride in the wet (water in the bb shell will mean regular inspection/cleaning/greasing if you want to avoid short bearing life or corrosion)

if should creaking occur in future, you can use a retaining compound (ffs use a low strength one), chances are that'll resolve any issue unless the felt shell is really poor

fwiw my bb30 frame has had 7+ years all weather riding without creaking (sram bb30)

assuming no installation/other issues, rapid bearing wear mentioned above could be an alignment problem in the bb shell, probably not much can be done about that if it happens

i'd expect at least 15,000-20,000km out of a set of bearings, depends on riding conditions/maintenance though


with sram cranks, you have a choice of bb30 or gxp...

if you have bb30 bearings, the obvious is to get bb30 cranks

but you could choose to put in a bb30 bearing plus adaptors to gxp spindle, and use gxp cranks if you wanted to keep an option to use the cranks on non-bb30 in future

a quick google for felt bb30 creak didn't show anything about felt, on that basis i'd go bb30 bb+cranks

jaron09james

Damn you guys are good! sungod and thepainandsuffering, this all makes sense now - thank you, just what I needed.

I'm hoping the shell and shoulder are top notch, Felt must have had a lot of confidence in themselves to essentially do away with anything that can be fixed. Hope it's not famous last words.

Will go with the BB30 bearings and marine grease.

I can sleep without dreaming of BB's tonight...