How does this account for BB drop?
It seems like a standover dim is the acid test here. No one dimension will do it all.
Roman Stankus
Atlanta, Ga USA
> -----Original Message-----
> From: classicrendezvous-bounces@bikelist.org
> [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of
> Doug Van Cleve
> Sent: Sunday, February 11, 2007 9:55 AM
> Cc: classicrendezvous@bikelist.org
> Subject: Re: [CR] Frame sizes/standards
>
> Howdy folks.
>
> While I understand both sides of this "arguement", to me C-T
> is the only measurement that really lets me know if a bike
> will be okay.
> >From a theoretical geometry perspective I can see why C-C might be
> best, but from a practical body/bike perspective C-T is what
> matters to me. With the wide range in tube diameters and
> shapes that now exist, knowing where the part that will
> directly impact my anatomy is the most helpful (if I know the
> BB drop or height). I measure right in front of the seat
> post at the very top of the top tub. Measuring to the tip of
> the lug or top of the seat tube where it extends above the
> top tube doesn't provide anything useful. Just my $0.02...
>
> Doug Van Cleve
> Chandler, AZ USA
>
> P.S. Roman, using your example an old 531 Trek and a new OT
> OCLV Trek could have the same geometry but the new one with
> big tubes could easily be 1cm taller in standover. If I am
> already on the tallest frame I'm comfortable with that could
> be the deal breaker...
>
>
> On 2/11/07, Ken Freeman <freesound@comcast.net> wrote:
> > Brian,
> >
> > I hope this isn't seen as thread hijacking, but let me ask
> a question
> > that is related to measuring standards:
> >
> > The hard part in c-t measurement, if there is one, is to know where
> > the top of the top tube is. Faliero's method removes this
> ambiguity,
> > at the expense of generating practical data. Even on a
> lugless frame
> > you have to eyeball it carefully to see the top, and skill
> and experience are important tools.
> > If there is a seat lug, should you measure from the top of the lug
> > where it covers the seat tube (which is at least visible),
> or should
> > you measure from the top of the top tube even if you can't
> see it under the lug?
> >
> > A friend and I were working together to try to understand why the
> > standovers of our two Treks seemed subjectively so
> different to him.
> > The actual difference was only a few millimeters. However, the
> > difference in physical pressure was deemed to be significant to my
> > friend, resulting in him not being interested in buying my
> frame (just
> > as well, as it turned out!). But, it shows that a few mm
> can make a difference.
> >
> > Ken Freeman
> > Ann Arbor, MI USA
> >
> > -----Original Message-----
> > From: classicrendezvous-bounces@bikelist.org
> > [mailto:classicrendezvous-bounces@bikelist.org] On Behalf Of
> > brianbaylis@juno.com
> > Sent: Sunday, February 11, 2007 12:22 AM
> > To: fatticbicycles@qtm.net
> > Cc: classicrendezvous@bikelist.org
> > Subject: Re: [CR] Frame sizes/standards
> >
> >
> > Doug,
> >
> > Good stuff! Regarding how Masis were measured; they were
> measured to
> > the top tip of the point of the seat lug, which makes
> absolutely no sense at all.
> > Most c-t measurements are from BB center to top of top
> tube. That's my
> > preference. If someone wants a frame speced on a c-c
> dimension; I draw
> > it that way, but when I stamp the frame size in the BB
> shell it will
> > say 55.2cm, which is a 54cm c-c frame with a 1" TT. In this way the
> > customer gets the "size" frame they understand or prefer
> but my sizing
> > is consistently c-t in cm.
> >
> > Brian Baylis
> > La Mesa, CA
> >
> > -- Doug Fattic <fatticbicycles@qtm.net> wrote:
> > Roman Stankus asked:
> >
> > Here's a question that relates to framebuilding and history of the
> > craft so I will beg forgiveness to cross-post to
> Framebuilders and CR list.
> >
> > Does anyone have any insight about using c-c vs c-t dimensions for
> > seat tubes lengths when describing a frame size. It seems that most
> > Italian builders used c-t dimensions. Was there a reason
> for this vs c-c dimensions?
> > Did it have to do with the build process itself in some
> way? Did these
> > methods of measure change over time for any reason. Are there any
> > build traditions where the top tube is not measured c-c as
> is the norm now?
> >
> > Roman Stankus
> > Atlanta, Georgia
> > USA
> >
> > Hi Roman,
> >
> > I suppose I have some obligation to answer this question since it
> > unfortunately dawned on me I might have probably been around good
> > bikes longer than about anyone else on the framebuilder
> list (but not
> > the CR list, whew). My dad got me my first 10 speed in
> 1963 and that
> > was after having to wait a couple of years for it while we were in
> > Rwanda and I went to high
> >
> > school in India. I got my first used Italian frame with
> Campy (gran
> > spo rt
> > derailleurs) parts in 1966.
> >
> > At that time in the states, everything I knew about was measured
> > center to top in inches. And it fact we (as in American
> enthusiasts)
> > tended to believe we needed bigger frames that what was necessary
> > because of the dominance of Schwinn in the American market -
> > particularly outside of th e biggest cities. Most likely
> somewhere on
> > the list of bicycles owned wou ld be either a Schwinn Varsity,
> > Continental or Super Sport. These were measured center to the very
> > top of the seat tube (cut straight across) i n inches.
> Schwinn seat
> > tubes stuck up quite a ways above the top tube so a collar
> with a bolt
> > could be slipped over it to tighten the seat post (as is
> common today
> > on tig welded frames). This made a Schwinn 22" frame actua lly
> > smaller than one of the same size from Britain because it's
> top tube
> > wou ld be lower down. I remember framebuilders in England
> in the 70's
> > would complain to me all the time about Americans wanting
> frames that
> > were too big for them. If a person's bike history included
> a Schwinn
> > and he used that as a sizing guide, he was likely to ask
> for a frame 1" bigger than what he needed. It didn't help
> that those bikes were made in only even sizes.
> >
> > I've always thought that the way Masi frames were measured
> (c-t) was
> > the
> >
> > exception for Italian frames and not the rule which was
> usually c-c.
> > Br ian B. could say where that top point actually was/is.
> When I got
> > a Masi in
> >
> > Italy in 1972, several letters in Italian (I used a
> translator) went
> > bac k and forth about my measurements and Masi made me a
> 57cm frame.
> > When tha t frame got stolen, I asked for a 58 and got one
> that size.
> > Faliero stamp s the size on the bottom bracket shell. When
> I measured
> > it, it was more l ike a 57cm c-t but I thought that was
> because he was
> > stubborn and made me th e size he thought it should be
> anyway and put
> > the size I wanted on it just to please me. It wasn't
> until I was on
> > the CR list I discovered he measure d frames differently.
> >
> > One of the first questions I asked Jack Briggs when I was
> learning in
> > England is where exactly is the Point where the "top' is.
> He thought
> > th is British way didn't have a precise point. For example
> my 22 1/2"
> > Hetchin s seemed a little small. Where Jack measured from is where
> > the very top o f the top tube touches the seat tube. When
> I started
> > building frames, I u sed a center to top measurement in
> inches as well
> > because that was the syste m most customers understood. In my own
> > records, I would record the center to center measurement.
> Sometime
> > in the 80's in the states, the culture changed and
> customers started
> > to expect their frame size to be given c-c in centimeters. I think
> > this also reflected a change from Americans primar ily
> getting English frames like a Bob Jackson to Italian ones
> like Colnago.
> >
> > I will add that on many frames I've made, the controlling factor in
> > determining frame size is it's top tube height. This is because of
> > the need for some customers to get the handlebars up at a
> comfortable
> > height compared to the seat. I will set the top tube at whatever
> > height off the ground gives the right clearance. The
> result is odd c-c seat tube sizes.
> >
> > Doug Fattic
> > Niles, Michigan