Weight savings with a titanium bottom bracket
 

Does anyone know the weight difference between a stel and a titanium bottom bracket? Probably a Phil Wood 122 mm square taper. I an specing out a new build and am trying to decide if the cost for a titanium bb is worth the weight savings.

It's not like all spindles are identical or that the weight savings is the same. Go to the manufacturers site, pull down the weight specifications for each BB and subtract.

Look it up.

Check out White Industries too. Lighter yet.

i agree with what's been said. you've got to dig a little for specific info.

as an owner of two White Industries titanium BBs. i'd say they are pretty light. of course that's not exactly an industry standard metric. :lol:

i happen to like the minimalistic design. on old fashioned spindle, sans races, two cartridge bearings, two aluminum retainer cups and an aluminum lockring. they don't offer them in a lot of different lengths...

OTOH, a new build just got a shimano un72 that i bought for a song a while ago from Jensonusa.

I looked at the Phil Wood web site and they give weights under the "store" tab.

A stainless steel 123 mm JIS bottom bracket is listed as 234 grams and $131
The same 123 mm configuration with a Ti spindle and an aluminum shell is listed at 156 gm and $205
The same 123 mm Ti spindle and a magnesium shell is given as 154 grams and $322.

Stainless English mounting cups are 34 gm and $30/pair
Aluminum English mounting cups are 11 gm and $47/pair

If you are looking for weight savings you might want to consider options besides square taper..

+1 for looking at actual weights, rather than useless generalizations.

Thank you. I did try to look up but did not see weights listed where I was on the site. I guess I was in the wrong place. I will look at the White Industries hubs too. I am stuck with square taper with my cranks. I am hoping to shed a pound of final weight with a budget of about four hundred extra bucks and trying to figure out where I reduce the most weight for what I spend.

Thanks for the info

Take less water with you next time you ride. You'll save just about as much weight.

N/m

Not necessary. The info is shown above. the one that gets me is the magnesium/Ti combination. You pay $117 more to save 2 grams!

I would look elsewhere. Put some of the more common suspects on the scale and see where that gets you. Seatpost, saddle, bars, stem, etc. Tires are a place to potentially save a lot of weight. Depending on what fork you're running you could probably lose some there too. Wheelset obviously.

wow titanium bottom bracket is sure new stuff on my ear LOL, should you consider look into new bb ht2 and new crank? with $400 you can get xtr level.

In my view the time spent on sourcing, ordering and installing lighter components assists speed far less than would spending the same time on the bike. In addition, wearing better fitting clothing would probably offer more benefit at speed. Taping your shoelaces saves .8% at only 22 mph and shoe covers 1.4%, which is more than you will gain with even a 1 lb decrease in weight.
http://sheldonbrown.com/rinard/aero/aerodynamics.htm

Remember that not only is weight less a factor (except when climbing) but that you have to add your own weight to the bike to evaluate how much you are saving. So my opinion would be that the bb cost would not be worth the money. A better use of your money might be to get professional fitting or coaching.

But the bottom bracket has _rotating_ components . . . think of the reduced rotational inertia!

Leave your Chapstick at home and buy a normal BB.

I remember back in '76 a friend of a friend in college showing us some of his fancy bike stuff including a Ti crank spindle. It was the first Ti I ever saw and got to heft. It was amazingly light. Back then they were breaking so fell into disfavor. I'm sure all that is ironed out now...though a big fat thin-walled Al tube like in modern GXP and press-fit systems is probably a superior design, IMO.

edit: senior moment...upon reflection I realized it was in 1972, not '76.

Back then the Ti used was "CP grade" (chemically pure) grade which is weaker and has a much poorer fatigue life than currently used 3Al/2.5V or 6Al/4V alloy. The Teledyne Titan, one of the first Ti bike frames, was made of CP-grade and had a well deserved reputation for breaking.

Even with the much stronger Ti alloys used today there are some recommended rider weight limits. Speedplay says their Ti axle pedals should be limited to a maximum of 185 pound rider weight.

Go on a diet. When you are 5% body fat then worry about a few ounces on the bike.

You are either joking or an example of a little knowledge being a dangerous thing.

If you'd read the post through video skype, I suspect you'd have seen the tongue planter firmly in his cheek.

Weight weenie threads always draw some skeptical replies. Lose your own blubber, who cares about climbing 0.01% faster, empty your bowels, first world problems, blah blah.

Okay, that said - what's the details on your bike: current weight, model, what are all the components, and why did you settle on the BB as the place to trim weight?

I did the same thinking on one of my bikes and the BB came up as a logical place to trim. However, most other components were already very light OR were "off limits" for aesthetic reasons. Are you in that situation? Because, normally, I'd look to tires and rims (tubular rims and light tubular tires), saddle (carbon fiber shell, Ti rails, minimal padding, available used for $100), seatpost, and don't overlook the chain (if you have a heavy one, there is good gram/$ potential). Do you object to a carbon fiber crankset?

Anyway a White Ind Ti BB is 162 grams and "only" $180. That includes cups.

This isn't a great idea.

Here's why: what you'll easily notice more than losing 100g in the BB is a stiffer 2-piece crankset like a Hollowtech II or something, and titanium is flexier than steel. You can find such cranksets second hand these days which means you find something much stiffer and lighter within your budget if you ditch the square taper cranks.

And anyway, it's one of the least noticeable places on the bike to save weight. After tyres and rims, it's the seat, then bars/stem/seatpost, on down the bike.

dp

I thought it was a good idea to get ti b/b to go along with my ti mtb. It worked for a while, then that thing creaked like crazy, every pedal stoke is agony. When I tried to remove it, that thing wouldn't budge. The aluminum cup is stuck real tight and I had to whack it out with a hammer and dot punch.

Which is why you use a lot of heavy grease, or better, antiseize or, better yet, teflon tape on the threads of any bottom bracket you install in a Ti frame. Aluminum cups make it even more important.