I opined to Chuck that a bbd of 8cm is in my mind a low BB and a 6.5 cm one is a high bb, assuming 700C tubulars with (let's just say) a 336.5 mm radius, corresponding to a 22 mm tire, 22.622.
Dale's threshold height for "low" is 10.5 inches, or 26.7 cm. His threshold for "high" is 10.75 inches or 27.3 cm. Using my 22.622 tire radius, the BBD for a low bb is 6.95 cm, and the BBD threshold for "high" is 6.35 cm. My idea for high does not agree with Dale's, and my idea for low does. I defer to Dale's experience as a builder, whereas I just play with math.
Ken Freeman Ann Arbor, MI USA
-----Original Message----- From: classicrendezvous-bounces@bikelist.org [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of oroboyz@aol.com Sent: Sunday, December 31, 2006 5:35 PM To: classicrendezvous@bikelist.org Subject: [CR]BB height, what's considered high or low?
OK, let's state some accepted practices:
Generally speaking, for traditional road bikes: - below 10 1/2" is in the "low" range.. - 10 1/2" -10 3/4 " is moderately normal - above 10 3/4" is high...
'Course all things are relative. Obviously tire size can change things Dale Brown Greensboro, North Carolina USA
-----Original Message----- From: chuckschmidt@earthlink.net To: classicrendezvous@bikelist.org Sent: Sun, 31 Dec 2006 12:18 PM Subject: Re: [CR]Was: Woodrup frames. Now: BB height, etc.
A fascinating aspect to this whole discussion of high and low BB height is that there hasn't been a single dimension mentioned as to what would be considered a high or low BB.
Hilarious...
Chuck Schmidt South Pasadena, CA
On Dec 31, 2006, at 6:41 AM, oroboyz@aol.com wrote:
> Hey Ken:
>
> I can't help but wonder about a couple of things you wrote here:
>
> << Mine (1980, pre-TSD) also has a high BB, the drop is about 6.4 > cm.
Compares > > to about a cm more for my Trek and others. I think this >
contributes to the > > Woodrup's sense of stability. >> > > > > "In
Theory" the lower the BB, the more stable and of course the > opposite for
> > higher BBs.
>
>
>
> In fact, if I remember correctly, that is one of Richard Sach's unique >
> characteristics in his frames... He has used quite a bit lower bb > height
> > and while you may not be able to pedal through the curves quite as >
much, > > that is a well considered trade-off that results in a more
secure > control > > (stability)while cornering.
>
>
>
> I think that much of the sought after stability and steering > accuracy
is part > > of accurate frame alignment and dishined wheels... So many
frames, > of all quality > > levels, are not straight.. Just a 1/2 CM in
misalignment can make a > huge > > difference and we tend to blame other
factors (frame angles, > dimensions) > > when in fact, if the frame were
carefully aligned, would make the > bikes > > ride ever so much better....
>
>
>
> << My theory is that both of my frames are small frames, and > subject to
> > compromises inherent in minimizing toe overlap and gettign adequate >
front > > tire to downtube clearance, without extremely long top tubes.
One > design > > feature to address this is to raise the BB, and another
is to lay > back the > > head tube to perhaps 72 degrees. >> > > > >
In my (limited) experience, the reason many builders/manufacturers > make >
> a higher BB in smaller frame is to solve the problem/save a lot of > work
> > in joinery at the compacted head tube /head lugs area...
>
> By raising the BB, that allows raising the upper head lug, > allowing
quick and unmodified use of the > stock lugs. I.e., no cutting or fitting,
etc. Another solution to > this was a one-piece head lug > that allowed the
top tube & down tube to intersect...
>
> On road bikes of any size, I don't think > the clearance of the down
tube vs tire is much concern...
>
> 'Course I could be wrong. It is fun the theorize about all this >
mysterious stuff!
>
> Happy New Year!
>
> Dale
>
>
> Dale Brown
> Greensboro, NC USA
>
>
>
>
>
> -----Original Message-----
> From: freesound@comcast.net
> To: jerrymoos@sbcglobal.net; hydelake@verizon.net; >
Classicrendezvous@bikelist.org > Sent: Sat, 30 Dec 2006 7:43 PM > Subject:
RE: [CR] WOODRUP frames > > Jerry, > > Mine (1980, pre-TSD) also has a
high BB, the drop is about 6.4 cm. > Compares > to about a cm more for my
Trek and others. I think this > contributes to the > Woodrup's sense of
stability. The SOH on mine is 77.6 cm, seat > tube is 53.5 > c-t, 52 cm
c-c.
>
> My '84 or so Mondonico (sure looks on-topic, but I can't be sure!) > has
a BB > drop of 7.2, 52 cm c-c seat tube, and 78.3 cm SOH. Both bikes seem >
to have > high BBs, so I don't think national style is necessarily being >
illustrated > here. My theory is that both of my frames are small frames,
and > subject to > compromises inherent in minimizing toe overlap and
gettign adequate > front > tire to downtube clearance, without extremely
long top tubes. One > design > feature to address this is to raise the BB,
and another is to lay > back the > head tube to perhaps 72 degrees. My
Woodrup and Mondonico > respectively have > head tube angles of 72.0
degrees and 72.4 degrees (I have less > confidence in > this latter
number).
>
> Both bikes are sort of a French fit for me.
>
> Ken Freeman
> Ann Arbor, MI USA
>
>
>
> -----Original Message-----
> From: classicrendezvous-bounces@bikelist.org
> [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of Jerome & >
Elizabeth Moos > Sent: Saturday, December 30, 2006 11:56 AM > To: Barb &
Dan Artley; Classic Rendezvous > Subject: RE: [CR] WOODRUP frames > > I
have an early/mid 80's Woodrup. Nice bike, but does have a very > high >
bottom bracket. Haven't measured the actual BB height, but the > standover
> height is what I'd expect on a bike with a seat tube about 2 cm > longer.
No > one else has mentioned this, but were high BB's typical of > Woodrup?
On the > other hand I also have a 52 cm ctc 1988 Mercian KOM with a >
standover height > about the same as a 55 cm French of Italian frame, so
maybe the > high BB's > were a British thing in the 80's.
>
> Regards,
>
> Jerry Moos
> Big Spring, TX
>
>
>
> Barb & Dan Artley <hydelake@verizon.net> wrote:
> I can't say how pleased I am hearing so much of Woodrup Cycles. A >
Woodrup > was my first really nice race bike replacing what I considered
more > of a > tourer, my PX-10 (Sorry Peter K.). It was unfortunately
crashed, badly > repaired and sold, but recently repurchased. I'm hoping
that > someday it will > get the restoration it deserves for the fond
memories of my only > race season > back in 1973. Thanks to all who've
provided this information. Does > anyone > know if they are still building
keepers of the flame in lugged > steel? ...
> More?
>
> Dan Artley in Parkton, Maryland
>
> Archive-URL:
> http://search.bikelist.org/
> 1653.eml
> Date: Fri, 29 Dec 2006 21:57:24 -0500 > Subject: RE: [CR] WOODRUP frames
> From: Doug Fattic > > The subject of Woodrup frames reminds me of my own
experiences > visiting > their framebuilding shop when I was learning to
build at Ellis Briggs.
> I
> wanted to learn how to do a fluted seat stay top like what was on > my
Masi > and Jack Briggs rang up Woodrup to see if one of them would be >
willing to > show me how. What I vaguely remember Jack Briggs telling me
was > that somehow > Jack's father helped Woodrup get started. The date
around 1953 or 4 > sticks > in my mind from our conversation about it.
Leeds is about 15 miles > to the > east from the much smaller town of
Shipley where Ellis Briggs is > located.
> The good size city of Bradford is about 3 miles to the south.
> In
> other words, these places are one big megalopolis. 15 British miles > is
not > 15 American miles. The roads are not laid out on a square because >
of the > shape of the land and going to Leeds seemed like a big trip. It
was > lots of > stop and go city driving on winding roads in my old Morris
Minor. This > generosity (to help others when it wasn't to his own
advantage) was > part of > Jack's character too and something I've been
deeply grateful for > (since he > did the same for me).
>
> I was a little shy going in the door and was glad Jack had asked >
permission > for me. One of the sons (I don't remember which one) spent
several > hours of > the afternoon showing me what to do. That day he was
the only one > there. I > had some seat stays with me and he demonstrated
how to miter the > end and > braze another piece of tubing in that place
and then file off the > excess. I > looked around a bit and realized they
did things a bit differently > than > Briggs. I also remember him
suggesting to me that there wasn't much > need now > days (as in 1975) to
pin frames together before brazing since > hearth brazing > was replaced
with oxyacetylene brazing. As he explained, a spot > isn't likely > to
break or move. All in all a valuable and pleasant afternoon. As > a newbie,
> I was respectful of his advice and didn't try to argue how we did > things
a > bit differently at Briggs. My impression was that Woodrup was a bit >
more > production oriented - meaning that they concentrated on getting a >
certain > number of frames made in a decent way in a week.
> It
> was the primary thing that brought in money for them. The frame > shop at
> Briggs when I was there was a bit more of an extension of the bigger >
business. There was the regular retail sales on the ground floor with >
several sales people. There were the regular Raleigh and other > bikes and
> another area had pro stuff. In the back was the repair shop with 2 >
workers.
> Upstairs in one room was Bill and Rodney the painters and in > another,
Andrew > mostly made the frames one at a time to a particular person. The >
result of > not having framebuilding be the center of the business was that
it > allowed a > bit more individual attention to be paid to each frame
being made. > Jack > never pressured Andrew to be more productive, he just
wanted him to > make > them right. Jack himself also helped out in there
but mostly he and > his wife > kept an eye on the entire business. When he
was in the frame shop, > it was > primarily to teach me and share his
considerable knowledge or finalize > instructions about another frame for
Andrew to build. Those > circumstances > really were a benefit to me which
I have always deeply appreciated.
> Another
> advantage was the ability to wander into the paint room next door and >
observe all the steps in painting. Bill and Rodney always enjoyed > company
> and Andrew and I also ate our lunch in there.
>
> There are lots more memories of that time but not more time to > write
about > them now. About the other framebuilders in West Yorkshire and the
area > itself.
>
> Doug Fattic
> Niles, Michigan USA
>
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