Bottom Bracket sizing help.

Sorting out your thrunge brackets, fettling your inter-rositers and even stuff about bike parts.
zer0c00l44
Posts: 5
Joined: Sat Sep 29, 2012 22:41 pm

Bottom Bracket sizing help.

Postby zer0c00l44 » Sat Oct 06, 2012 02:24 am

Hi Guys Im a little confused, Ive just purchased a Mojo SL and I want to know if I can fit a bb30 chainset its an FSA K force light bb30 10 speed and the bottom bracket of the SL is a 68mm english thread.

Can you buy an adapter, is it easy to fit as I want to do it myself and will there be much of a weight penalty.

Any help will be greatly appreciated

thanks :D

User avatar
The Rookie
Posts: 23069
Joined: Thu Apr 30, 2009 09:29 am

Re: Bottom Bracket sizing help.

Postby The Rookie » Sat Oct 06, 2012 06:42 am

The ibis webby is singularily useless at identifying what the farme takes....
http://www.ibiscycles.com/bikes/mojo_sl/
What does it say the BB is?

User avatar
warpcow
Posts: 1435
Joined: Mon Jan 11, 2010 15:10 pm

Re: Bottom Bracket sizing help.

Postby warpcow » Sat Oct 06, 2012 07:29 am

You can get adapters to go the other way (to fit 'normal' cranks in a BB30 frame), but not the way you're wanting.

User avatar
nicklouse
Lives Here
Posts: 80713
Joined: Thu Mar 20, 2003 12:14 pm

Re: Bottom Bracket sizing help.

Postby nicklouse » Sat Oct 06, 2012 07:55 am

zer0c00l44 wrote:Hi Guys Im a little confused, Ive just purchased a Mojo SL and I want to know if I can fit a bb30 chainset its an FSA K force light bb30 10 speed and the bottom bracket of the SL is a 68mm english thread.

Can you buy an adapter, is it easy to fit as I want to do it myself and will there be much of a weight penalty.

Any help will be greatly appreciated

thanks :D

In a word no.
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools :?:SheldonBrown

User avatar
cborrman
Posts: 82
Joined: Sat Feb 28, 2004 19:09 pm

Re: Bottom Bracket sizing help.

Postby cborrman » Sun Oct 07, 2012 22:31 pm

I have been looking at this for a while, ever since I saw the story on this site of ned overend from specialized racing a rockhopper sl (68mm english) with the specialized bb30 cranks... To cut a long story short, in some cases it can be done but in others it cannot, the ones who have managed have done it with the zipp vuka or one of two other specialist bb cups, and a bb30 crank with the right length spindle... Happy googling ;)

User avatar
nicklouse
Lives Here
Posts: 80713
Joined: Thu Mar 20, 2003 12:14 pm

Re: Bottom Bracket sizing help.

Postby nicklouse » Sun Oct 07, 2012 22:48 pm

cborrman wrote:I have been looking at this for a while, ever since I saw the story on this site of ned overend from specialized racing a rockhopper sl (68mm english) with the specialized bb30 cranks... To cut a long story short, in some cases it can be done but in others it cannot, the ones who have managed have done it with the zipp vuka or one of two other specialist bb cups, and a bb30 crank with the right length spindle... Happy googling ;)


yes you can get cups that are fitted with bearings that will pass a 30mm axel BUT that then makes the BB too wide so you can not use BB30 cranks.

so back tom the OP Not possible.
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."

Parktools :?:SheldonBrown

User avatar
cborrman
Posts: 82
Joined: Sat Feb 28, 2004 19:09 pm

Re: Bottom Bracket sizing help.

Postby cborrman » Mon Oct 08, 2012 06:12 am


User avatar
cborrman
Posts: 82
Joined: Sat Feb 28, 2004 19:09 pm

Re: Bottom Bracket sizing help.

Postby cborrman » Mon Oct 08, 2012 06:18 am

cborrman wrote:I have been looking at this for a while, ever since I saw the story on this site of ned overend from specialized racing a rockhopper sl (68mm english) with the specialized bb30 cranks... To cut a long story short, in some cases it can be done but in others it cannot, the ones who have managed have done it with the zipp vuka or one of two other specialist bb cups, and a bb30 crank with the right length spindle... Happy googling ;)


From a few googles i think you are in luck, see link above, issue is if the bb is 68 or 73mm, it is the latter like it was on my old 2009 s-works stumpy then no spindle fits, but you have 68mm, howver some spindles may still be too short. There was another thread for cannondale hollowgrams where a chap in US was machining slightly longer spindles n' all ;)

Happy googling (i spent hours)... You will also come across many "it cannot be done" purists but keep persevering, i am in process of getting some for my kona unit... All i need now is some spare time ;(

User avatar
nicklouse
Lives Here
Posts: 80713
Joined: Thu Mar 20, 2003 12:14 pm

Re: Bottom Bracket sizing help.

Postby nicklouse » Mon Oct 08, 2012 07:16 am


that is NOT a BB30 crankset.
"Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."

Parktools :?:SheldonBrown

User avatar
cborrman
Posts: 82
Joined: Sat Feb 28, 2004 19:09 pm

Re: Bottom Bracket sizing help.

Postby cborrman » Mon Oct 08, 2012 08:18 am

THM carbones was the other bb cups;

http://forums.mtbr.com/weight-weenies/w ... 79587.html

From the above link:
"German company THM Carbones makes a 68mm BB cup set to allow standard Hollowgram SL BB30 crankset to work. Starbike (Weight Weenies site) sells them for about 140 Euros/set.

I also think Zipp Vuma Quad BB will also work too..."

Note as they say tho, some spindles work, others do not, its seems to be down to how they lock and length of the arm fitting from what i can see.

My conclusion has been that xtr and/or lighting cranks is easier...

zer0c00l44
Posts: 5
Joined: Sat Sep 29, 2012 22:41 pm

Re: Bottom Bracket sizing help.

Postby zer0c00l44 » Wed Oct 10, 2012 01:35 am

Thanks for the replies guys appreciate it.


Return to “MTB Workshop & Tech”

Who is online

Users browsing this forum: No registered users and 4 guests