Re: [CR] Measuring Frames


Example: Racing:Wayne Stetina

Date: Wed, 13 May 2009 09:14:48 -0700
From: <mrrabbit@mrrabbit.net>
To: Michael Howard <95rivieramike@gmail.com>
References: <8CBA1F02432375A-CC8-2592@webmail-mf04.sysops.aol.com> <905765.27626.qm@web82206.mail.mud.yahoo.com> <68924d350905130845h71a45ba0m7e27f62d866f8648@mail.gmail.com>
In-Reply-To: <68924d350905130845h71a45ba0m7e27f62d866f8648@mail.gmail.com>
Cc: jerrymoos@sbcglobal.net, classicrendezvous@bikelist.org, bobhoveyga@aol.com
Subject: Re: [CR] Measuring Frames


Stole my words right out of my piggy bank Mike...

=8-)

Robert Shackelford San Jose, CA USA

Quoting Michael Howard <95rivieramike@gmail.com>:
> Ah, but center to center opens up a whole new can of worms. A 55cm center to
> center will be different on a frame with a 1" top tube than say a Cannondale
> with a mega top tube. That is why I have always measured (on my
> drawings) from Center of BB to the intersection of the top line of the top
> tube and the center line of the seat tube. That is usually, on most seat
> lugs, right where the edge of the top of the seat lug is on the side of the
> frame where most people use to measure frames. Hope I explained that clearly
> as it was always the only way to measure a frame consistently regardless of
> tube diameters.
>
> Mike Howard
> Santa Fe Springs
>
> On Wed, May 13, 2009 at 8:17 AM, Jerome & Elizabeth Moos <
> jerrymoos@sbcglobal.net> wrote:
>
> >
> > The problem with this approach is that the standover height will vary if a
> > different seatlug is used or if the seattube extends above the toptube.
> > Fillet-brazed Schwinns were measured this way, but the seattube extended
> > maybe 1 1/2" above the toptube, so they are much smaller than the stated
> > size might lead one to believe. Mercians are also measured this way. I
> > forgot that when I bought a KOF Mercian KOM on eBay, and wound up with a
> > frame 2 cm smaller than I expected. Fortunately, many Mercians, including
> > this one, have a very high BB, so the standover ended up being about
> right.
> >
> > This does bring up the point that, regardless how the frame is measured,
> > one still does not know the standover height, as that will be affected by
> > frame angles and even more by BB height. So the best way to know
> standover
> > is if the seller actually measures and states it. But if one has to buy
> > based on a frames size only, c-t-c size will at least remove variables
> like
> > extended seattubes.
> >
> > Regards,
> >
> > Jerry Moos
> > Big Spring, Texas, USA
> >
> >
> > --- On Wed, 5/13/09, bobhoveyga@aol.com <bobhoveyga@aol.com> wrote:
> >
> > > From: bobhoveyga@aol.com <bobhoveyga@aol.com>
> > > Subject: Re: [CR] Measuring Frames
> > > To: classicrendezvous@bikelist.org, brianbaylis@juno.com,
> > raydobbins2003@yahoo.com
> > > Date: Wednesday, May 13, 2009, 9:42 AM
> > > Brian writes;
> > >
> > > >> I had no idea there might be others who used the
> > > tip of the seat lug as the measuring standard. Any idea why
> > > those who choose this method prefer it? It seems center to
> > > top of top tube makes sense, as does center to center. But
> > > why to the tip of the seat lug? Maybe someone has an
> > > explanation...
> > >
> > >
> > > Brian, I think there might be a clue in Ray's earlier
> > > message... when asked why the measure was made to the tip of
> > > the seat lug, he said that Alberto replied that it was
> > > "consistent."? But consistent with whom??
> > > Certainly not other builders... Ray suggests that he meant
> > > consistent with his dad.?
> > >
> > > But I suspect Alberto may have meant "consistent from
> > > measurement to measurement."? After all, the tip of the
> > > seat lug is a single, discreet point:? Easy to see, no way
> > > to get it wrong.? But consider the C-T measure as performed
> > > by various folks... builders, bike shop personnel, or
> > > newbies... sure, the center of the bottom bracket is pretty
> > > obvious, but where exactly is the top of the top tube?? Is
> > > it at the point where the top of the top tube and the front
> > > of the seat tube intersect?? Or is it the projected line of
> > > the top of the top tube where it intersects the centerline
> > > of the seat tube?? Or is it a vertical line, straight up
> > > from the bottom bracket, as one would measure standover
> > > height?? I've always measured the second way (along the
> > > centerline of the seat tube), but I've seen folks
> > > measure the first way (to the tube intersection at the front
> > > of the seat lug) and the resulting measurement is a bit
> > > different.? And though I don't know anyone who measures
> > > a vertical line, I suppose it actually kinda makes sense to
> > > measure frames this way because if you know the BB height,
> > > you could just add the two measurements to get a standover
> > > height.
> > >
> > > Same goes for C-C measure... you can take it at the point
> > > where the tubes intersect, or project a line to the center
> > > of the seat tube, or measure vertically (again, I don't
> > > know anyone who actually measures vertically, but an
> > > inexperienced person who is told to measure "from the
> > > center of the bottom bracket to the center of the top
> > > tube" might well take the shortest distance, not
> > > knowing he is supposed to follow the seat tube).??
> > >
> > > But a measure "from the center of the bottom bracket
> > > to the point of the seat lug" leaves little room for
> > > misinterpretation.? So in a way, the Masi (and Confente,
> > > Paramount, Woodrup, Bob Jackson and whoever else) method
> > > does kinda make sense.
> > >
> > > Bob Hovey
> > > Columbus, GA USA
> > > http://bhovey.com/masi