Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

BB compatibility

Reply

Old 12-19-10, 11:27 AM
  #1  
lint
Newbie
Thread Starter
 
Join Date: Dec 2010
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
BB compatibility

I'm converting my Dad's old Austro-Daimler Puch to a fixed gear. I want to put this crank on it >> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=280595792760. What kind of BB/Spindle would I need? The current BB is square tapered and has about a half-inch of threads coming off where the square part ends. I'm used to BMX cranks where the threading is inside of the tapered part... Is that what those cranks would require? I've looked at JIS BBs, which a lot of cranks seem to call for, and by the images it looks different than what is on the Puch. Could I use those cranks, and if not is there other cranks I could buy or should I get a new BB?

Thanks.
lint is offline  
Reply With Quote
Old 12-19-10, 11:51 AM
  #2  
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 30,953

Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 958 Post(s)
You have what is known as a "nutted" bottom bracket where the crank arms are held on with nuts that go onto the threaded stubs. The BMX bottom brackets you are more familiar with are "bolted" and the cranks are held by bolts that thread into tapped holes in the spindle. Other than the fastening method, they are the same. As a rule, bolted spindles are typically higher quality that nutted spindles.
HillRider is offline  
Reply With Quote
Old 12-19-10, 12:00 PM
  #3  
Bianchigirll 
Bianchi Goddess
 
Bianchigirll's Avatar
 
Join Date: Apr 2009
Location: Fort Wayne, In
Posts: 24,661

Bikes: Too many to list here check my signature.

Mentioned: 62 Post(s)
Tagged: 2 Thread(s)
Quoted: 820 Post(s)
i am sorry about your Dad's old bike. what model is it? depending on the model and condition you might be able to sell ti for enouigh to buy a nice FG from a place like bikesdirect.

now about your cranks/BB you will need a new BB for that crank. the one in your Dad's bike will be too long.

the difference in what you see is most aftermarket BBs usa bolt to hold the arms on rather than a nut like on your Dad's bike.
__________________
Bianchis '87 Sport SX, '90 Proto, '90 Campione del Fausto Giamondi Specialisma Italiano Mundo, '91 Boarala 'cross, '93 Project 3, '86 Volpe, '97 Ti Megatube, , '90 something Vento 603,

Others but still loved,; '80 RIGI, '80 Batavus Professional, '87 Cornelo, '09 Motobecane SOLD, '?? Jane Doe (still on the drawing board), '90ish Haro Escape
Bianchigirll is offline  
Reply With Quote
Old 12-19-10, 12:10 PM
  #4  
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 30,953

Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 958 Post(s)
Most important, you have to find out what threading the current bottom bracket has. Depending on it's age and actual country of manufacture it could be English, French, Italian or even (very rarely) Swiss. Once you know that, the rest is fairly easy. Is there anything engraved on the cups that might tell us?
HillRider is offline  
Reply With Quote
Old 12-19-10, 12:28 PM
  #5  
lint
Newbie
Thread Starter
 
Join Date: Dec 2010
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
this is the same bike. No indication of where the BB is from. Cranks say Japan. The bike was purchased new in the mid 80's; the model is "Pacifica." Are there other cranks you would suggest that would fit the BB? Or is the "nutted" bolt outdated?

Last edited by lint; 12-19-10 at 12:38 PM.
lint is offline  
Reply With Quote
Old 12-19-10, 03:44 PM
  #6  
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 30,953

Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!

Mentioned: 26 Post(s)
Tagged: 0 Thread(s)
Quoted: 958 Post(s)
OK, this is still a guess but I expect your bottom bracket threads are English, which is by far the most common and easiest to match and the "Japan" on the cranks makes it likely the taper is JIS.

You would do better to take the bike to a bike shop and get a crank and bottom bracket that match each other rather trying to figure out what spindle those cranks on e-bay need.
HillRider is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service