Is it safe? Ti bottom bracket spindles

"E Goforth" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I remember the famous case of Laurent Fignon's bottom bracket spindle
breaking. Are the newer Ti bottom brackets reliable?

Phil Wood states its ti bb spindles have a 225lb weight limit.

E Goforth said:

I remember the famous case of Laurent Fignon's bottom bracket spindle
breaking. Are the newer Ti bottom brackets reliable?

-Eric

I would say a big NO to titanium BB spindles or pedal spindles. They do
nuthin there, can break, hurts lots when they do.

bfd said:

"E Goforth" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

I remember the famous case of Laurent Fignon's bottom bracket spindle
breaking. Are the newer Ti bottom brackets reliable?

Quoted message said:

Phil Wood states its ti bb spindles have a 225lb weight limit.

A friend did some calculations on these once (square taper axles),
comparing them to steel, and came up with a safe rider weight about half
that. Is there an engineer in the house (of Phil)?

Matt O.

One thing about Phil ti spindles, unless others, it is a solid spindle,
not a hollow one as found on many others. I don't know if that makes a
difference in strength (or safety), but if you contact Phil Wood, they
will insist there's no problem for riders *under 225 lbs."

Maybe the question should be whether your "friend" who did these
calculation is an "engineer?" Has he examined a Phil Wood ti spindle?

Phil ti spindles are solid, not hallow like alot of other ti spindles.
Further, it is supposedly "heat-treated," presumably for greater
strength. If you contact Phil Wood, they will tell you that the ti
spindle has a weight limit of 225 lbs!

For more on PW ti bbs, go here:

Phil Wood premium ti bb:
http://www.philwood.com/Price%20List/TitaniumCrankBottomBracketSets.pdf

Phil Wood Proprietary Magnisium Titanium bb:
http://www.philwood.com/Price%20List/TitaniumMagniumCrankBottomBracketSets.pdf

Why bother? What do you think you might gain?
Larry

"bfd" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Maybe the question should be whether your "friend" who did these
calculation is an "engineer?" Has he examined a Phil Wood ti spindle?

Maybe he's a former metallurgist...

In article <[email hidden]>,

Hank Wirtz said:

"bfd" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Maybe the question should be whether your "friend" who did these
calculation is an "engineer?" Has he examined a Phil Wood ti spindle?

Maybe he's a former metallurgist...

Now I have to clean the monitor screen.

--
Michael Press

Matt O'Toole said:

bfd said:

"E Goforth" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Quoted message said:

I remember the famous case of Laurent Fignon's bottom bracket spindle
breaking. Are the newer Ti bottom brackets reliable?

Quoted message said:

Phil Wood states its ti bb spindles have a 225lb weight limit.

A friend did some calculations on these once (square taper axles),
comparing them to steel, and came up with a safe rider weight about half
that. Is there an engineer in the house (of Phil)?

I'm a relatively light 150-155 pounds, and thought I was probably in
the "safe zone" for using ti pedal spindles (which had a similar
weight restrictions). They did last quite a few years before the
right one snapped off instantly, sending me into the curb (a hairy,
scary ride in traffic that somehow didn't result in hitting a car or
the ground).

I'm not too bright, but I did learn a lesson that morning. Ti is
great stuff, but not for everything. In the case of pedal spindles
and bottom brackets, you really don't want to take a design that's
optimized for steel and convert it to titanium if you can't make other
changes (ie make the BB or pedal spindle diameters larger).

Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame

E Goforth said:

I remember the famous case of Laurent Fignon's bottom bracket spindle
breaking. Are the newer Ti bottom brackets reliable?

If you replace them regularly, which would be a fairly ruinous cost. Ti
does have a fatigue limit, but it's not as usefully high as that for steel.

bfd said:

Maybe the question should be whether your "friend" who did these
calculation is an "engineer?"

A bona fide, fair dinkum engineer, letters and credentials too
-- imagine that! I'd be stunned if the bike industry has anyone
of his caliber in their employ.

Quoted message said:

Has he examined a Phil Wood ti spindle?

What could be different or special about a Phil Ti spindle? They all have
the same taper, which is where they break. Steel has been known to break
under heavy riders, and Ti (of the same dimensions) is weaker than steel.

Matt O.

"Matt O'Toole" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

bfd said:

Has he examined a Phil Wood ti spindle?

What could be different or special about a Phil Ti spindle? They all have
the same taper, which is where they break. Steel has been known to break
under heavy riders, and Ti (of the same dimensions) is weaker than steel.

Are you saying that ALL ti spindles are the same? Phil's advertisement
states that its titanium spindle are a "Proprietary Composition Heat-Treated
( PC-HT ) Titanium spindle."

Is it not possible that Phil could have "developed" a stronger ti spindle? I
think without some sort of comparision, by an engineer or someone like your
friend, its difficult to tell.

On the other hand, if Phil is stating that its ti spindles have a rider
weight limit of 225 lbs, then it would be opening itself up to liability if
anyone 225lb or lighter breaks one.

bfd said:

Are you saying that ALL ti spindles are the same? Phil's advertisement
states that its titanium spindle are a "Proprietary Composition Heat-Treated
( PC-HT ) Titanium spindle."

Is it not possible that Phil could have "developed" a stronger ti spindle? I
think without some sort of comparision, by an engineer or someone like your
friend, its difficult to tell.

Yes, Phil have magically developed a Ti alloy and heat treatment that
makes it as strong as steel, but instead of living large off the
government teat (be that the US or USSR one) making submarines, they
prefer to sell their miracle material as bike parts.

Yeah.

Jasper

On Sat, 08 Apr 2006 11:23:47 -0700, Mark Hickey <[email hidden]>

Quoted message said:

I'm not too bright, but I did learn a lesson that morning. Ti is
great stuff, but not for everything. In the case of pedal spindles
and bottom brackets, you really don't want to take a design that's
optimized for steel and convert it to titanium if you can't make other
changes (ie make the BB or pedal spindle diameters larger).

You don't particularly want to take a design optimised for steel and
convert it to *any* other material without changing diameters, AFAICT. ALu
frames don't have large tubes as a fashion statement. Well, not
originally.

Jasper

Jasper Janssen said:

bfd said:

Are you saying that ALL ti spindles are the same? Phil's advertisement
states that its titanium spindle are a "Proprietary Composition Heat-Treated
( PC-HT ) Titanium spindle."

Is it not possible that Phil could have "developed" a stronger ti spindle? I
think without some sort of comparision, by an engineer or someone like your
friend, its difficult to tell.

Yes, Phil have magically developed a Ti alloy and heat treatment that
makes it as strong as steel, but instead of living large off the
government teat (be that the US or USSR one) making submarines, they
prefer to sell their miracle material as bike parts.

LOL!!!!!!

Actually, Philco doesn't need a DoD contract; they make ample $ off of
the grease and oil. ;-)

Quoted message said:

Yeah.

Jasper