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Praxis BB30A - could I buy the 73mm MTB option.

bristolpetebristolpete Posts: 2,255
edited April 2016 in Workshop
After having installed praxis 68mm adaptor to my evo and being hugely impressed, I bought another one as building a Synapse. But, I realise this is 73mm, so I googled praxis options who advise that they do not adapt or support the 73mm BB30A option.

However, looking at the webpage I realise that 73mm is MTB standard and they do this, in hollow tech II for Shimano cranks. Has anyone used this as a work around or option for BB30A as makes sense to me ?!?!? Would it work, or am I missing the point ?

https://praxiscycles.com/wp-content/upl ... ConvBB.pdf

Thanks in advance.

Posts

  • SecteurSecteur Posts: 1,971
    The problem is the "A" in BB30A, meaning asymmetric, so my understanding is that the MTB one won't work.

    I spoke to one of these adapter companies in 2014 about this and they said one of these adapters would never be possible for BB30A due to technical limitations, and given that 2 years on they still don't exist, I'd give up hope now!

    Your only option is the bung type adapter which seems pointless unless you are desperate to have a shimano chainset
  • bristolpetebristolpete Posts: 2,255
    Secteur wrote:
    The problem is the "A" in BB30A, meaning asymmetric, so my understanding is that the MTB one won't work.

    I spoke to one of these adapter companies in 2014 about this and they said one of these adapters would never be possible for BB30A due to technical limitations, and given that 2 years on they still don't exist, I'd give up hope now!

    Your only option is the bung type adapter which seems pointless unless you are desperate to have a shimano chainset

    Ah, it seems wheels do one, but having googled to death, I cannot locate it, other than the BB30 option. Any ideas where I can find one ??!?!

    http://wheelsmfg.com/bottom-brackets/ca ... pters.html
  • SecteurSecteur Posts: 1,971
    No the one they do is the bung type, nothing like the one you bought for your Evo I'm afraid, and is a rather poor fix.

    There is no direct equivalent of the very nice BB30 kit for BB30A

    It was Wheels Mfg that I spoke to and who confirmed there would never be one
  • bristolpetebristolpete Posts: 2,255
    Aha, today I found the solution.

    https://www.c-bear.com/en/products/bott ... face-rotor

    Spoke to them today, paid for the goods and being airmailed tomorrow. Job done, they advise absolutely spot on for BB30a post 2014 power pyramid design with the 73mm shell. Happy days...! I concur praxis is a cut above, but we used these guys when I was working with Specialized and the PF30 shells they created from the SL3 onwards if my memory serves correct, so all things being equal it will rival the praxis.
  • SecteurSecteur Posts: 1,971
    Well that looks just the thing!

    Do the two halves screw together for a super tight fitting, or is it just press in from each side?

    Would you be kind enough to post photos of the fitting process and the final look (before and after fitting the cranks)? I'd really appreciate that!

    I posted the exact same thread as this 2 years ago when I first got my Synapse BB30A but in the end I've not had a single BB creak and still haven't had to service the BB yet (mainly because I'm too scared if I touch it I'll end up with noises - best let sleeping dogs lie!).

    If this ends up being a good fix, I may use it as my chainset is getting worn and might replace it with a Shimano chainset
  • bristolpetebristolpete Posts: 2,255
    Secteur wrote:
    Well that looks just the thing!

    Do the two halves screw together for a super tight fitting, or is it just press in from each side?

    Would you be kind enough to post photos of the fitting process and the final look (before and after fitting the cranks)? I'd really appreciate that!

    I posted the exact same thread as this 2 years ago when I first got my Synapse BB30A but in the end I've not had a single BB creak and still haven't had to service the BB yet (mainly because I'm too scared if I touch it I'll end up with noises - best let sleeping dogs lie!).

    If this ends up being a good fix, I may use it as my chainset is getting worn and might replace it with a Shimano chainset

    Will do, I will let you know what the process is, whether there is a collar/sleeve and thread, I have no idea, but this was a godsend and brilliant comms via Bart at C-Bear - hopefully, it is coming via airmail so maybe be here early next week.
  • SecteurSecteur Posts: 1,971
    Brilliant - i'll be very interested to see!

    If you'd rather email the photos (easier than uploading and linking here), PM me for my email address :-)

    Cheers again and good luck!


    PS what was the reason you chose this one over the Kogel and BBInfinate solutions? As they are all so new and so few users, I can find very little information on which might be best.

    http://kogelbearings.mysimplestore.com/ ... ano-cranks

    http://bbinfinite.myshopify.com/product ... 2646724995
  • bristolpetebristolpete Posts: 2,255
    Followed a hunch, got in touch with c-bear and job done. Ceramic too ! Posted airmail yesterday, so hopefully be here soon.
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