Building BB's

[Olys45]

In the intro to the Scratch Built portion of the "Builds" folder/category Uncle Stretch makes a comment that we can use a Head Tube and Bottom Bracket off a donor bike, but everything else has to be scratch built. I totally agree with that and I have a question about BB's.

Where can a person find a tap big enough to scratch build a BB? I imagine it would be really expensive because of the size and application.

Is there any other way to build a BB?

After working on my 'bent trike I'm intrigued by the prospect of building my own bike in a cruiser/chopper style.

The curious mind just wants to know.

Cheers,

Oly

 

[dracothered]

Since you will most likely need to buy tubing for a BB it would be easier to buy a new BB that is already threaded. From what I have priced out on the steerer tube die for cutting the threads it was around $200 for the die and handle to hold the die. So I can only guess that a BB tap and handle would be up in that range. A threaded BB couldn't be much over $30.

Reusing a threaded BB carries no shame though.

 

[LukeTheJoker]

American style bb's for one piece cranks need no threading...

Luke.

 

[dracothered]

American style bb's for one piece cranks need no threading...

Luke.

True, but since he said something about threading that would mean he must be talking about a three piece crank set. If the OP is indeed talking about a one piece crank then you only need the right size tubing for the bearing cups to fit snugly.

 

[CCR]

Euro bb taps are around $150 bucks, need a left and right ... so make that $300 for the pair.

Seen kits from Park Tools, Var, Cyclo all around $500ish

too rich for my needs

 

[Olys45]

Thanks for the responses and for the heads up Luke!

I know reusing/buying a new BB for an otherwise scratch build is perfectly acceptable, but the "cool/wow/unique" factor(s) of sourcing all the correct tubing and purchasing only the very minor parts just strikes a nerve.

It must be my passive/aggressive Norwegian/German heritage coming out. That and I've always been amazed at how relatively simple a lot of things are once you get past the first layer of the proverbial onion.

That must come from working on aircraft that are the same age as most of my Brothers and Sisters. The mighty KC-135 Stratotanker will still be flying 20-30 years at a minimum. We are using updated WWII technology on aircraft that were built in the late 50's to early 60's to perform most of the USAF's mid air refueling.

Cheers,
Oly

 

[jerrykr]

You could use an American one piece crank sized tubing, and get a 3 piece crank adapter to "convert it" to 3 piece. Or, I may be mistaken, but I think you can get a sealed bearing 3 piece bb for the European sized bb tubing that does not need threads.

 

[CCR]

Along the lines of what jerrykr is saying ... A lot of the BMX bb sizes (including American) allow you to use pressed in sealed bearings. To me, that seems the cleanest way to go. In that case you'd just need to ream the bb shell to the right diameter and should still give you the "I made this work" feeling down inside

 

[user 135]

For a nice build, I would be inclined to buy one. Many professional frame builders dont' make there own either.
http://www.cycle-frames.com/bicycle-frame-tubing/73mm-LUGLESS-BB-SHELL-SUPER-LIGHT-BB.html

 

[deven_science]

For a nice build, I would be inclined to buy one. Many professional frame builders dont' make there own either.
http://www.cycle-frames.com/bicycle-frame-tubing/73mm-LUGLESS-BB-SHELL-SUPER-LIGHT-BB.html

I'll piggy back on what cman is saying. I buy new head tubes and BBs from Nova. They're only $10 each at the most, and they're clean and ready to go. I do often use HT and BB cut off of an old frame, but when I want nice, I buy them from the website he linked to.

 

[c.p.odom]

Bottom Bracket Shells ready to go starting at $4.25
http://www.cycle-frames.com/bicycle-frame-tubing/BOTTOM-BRACKETS/

 

[dracothered]

Here is another source for BB's http://henryjames.com/bicyle-parts/bike-bottom-bracket-shells.html