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So I have bought a bike with a PF30 (Specialized Diverge Sport). If I wanted to swap the chainset for a Shimano 105, will it just drop in, or do I need some form or adaptor etc?
HI,
Assuming your 105 runs on a "standard" 24mm axle like you would use with an external bearing threaded / HTII BB then you're going to need an adapter or specialist BB.
My Camber (PF30) has a Hope PF46 BB in it which performs that function. Just be really sure which of the 30mm "standards" you have as there are different versions of these BBs.
It's a spendy bit of kit and you'll need the fitting tool, which is a worthwhile investment to make bearing changes a doddle.
Other similar products are available.
The 30 refers to the spindle diameter, and Shimano is 24mm. So you'll need adaptors - most people seem to recommend Praxis.
PF 30 is basically BB30 with plastic cups to avoid having to make the BB shell to such tight tolerances. It uses the same 6806 bearings.
To get a 24 mm axle (Shimano + SRAM GXP) xhainset to work you need to either use adaptors like these
or a whole new BB like this
I think the new BB is a better bet. I have a bike running the adaptors and bearing life is fairly poor.
So I have bought a bike with a PF30 (Specialized Diverge Sport).
Poor sod! I'm just about to sell a bike with that piece of junk. If you throw a load of money at it then you can probably make it work or just ignore all the creaking and clicking sounds.
Drop one of these in the freezer overnight, pour boiling water over the frame BB, pull the adaptor in with a head set press/threaded bar. Run standard Shimano BB's again.
Have done this on two BB30 frames without problems.
https://www.chainreactioncycles.com/fsa-bb30-threaded-adapter-b3119-/rp-prod129935
Thanks for the tips. Given I need an adaptor I might just stick with the existing chainset for a bit and see how it does. I have a spare 105 chainset I was thinking of sticking on it, but that can wait for now....
Bit of a thread resurrection, but came across this amazing video about it, if you're an Engineer you'll be very impressed by this guy. He didn't like any of the conversion kits out there so just designed and made a better one...
Conversely my CAADX with BB30 has been creak free, I think specialized are know to have 'issues' with their implementation, which is why they're now making a big song and dance about going back to threaded shells!
Quite like the look of the praxis BB's, that's the route I was planning to go down if I ever got a stages/4iii power meter and wanted to swap between bikes. Irritatingly I actually have FSA chainsets on most bikes and zero shimano at the moment, but they're all different standards. Kudos to shimano for sticking with the same BB/spindle/spline for 15 years whilst the industry went a bit nuts!
Funny thing I was only thinking it would be nice if Mr Hambini was on here 🙂
I just use a 'wheels manufacturing' bb converter on my specialised bikes. Works a treat and I run shimonoseki cranks on all mine.
It’s about £60 which is not very cheap, but mine have all lasted years with only a quick remove/regressed every 12 months or so. This is easy and uses the same tool as a standard Shinano BB .
Funny thing I was only thinking it would be nice if Mr Hambini was on here 🙂
Only just come across him; his work on aero wheels is incredible. He must have put 100s of hours in.
First came across him on a GCN video about bearings - an interesting discussion on the differences between sealed and cup and cone bearings and why they are suited to different applications.