Judging mtb frame size from photo?

Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

On Nov 3, 10:51*am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

Personally, I'm not able to tell size by photos. I've been in the
same situation you're in, however, and I find it easiest to ask the
person how tall they are, and what size pant inseam they wear. Then
compare that to my own, look at the saddle height, and I can usually
guestimate if it's in my ballpark or not. One problem with this
method is so many people ride with their saddles quite low, while
others ride with them at road-bike height, giving almost full leg
extension on the bottom of the pedal stroke. Personally I adjust my
saddle to the ride, so in one picture it might be quite high
(suggesting I was riding trails that didn't really test my technical
ability, and was more concerned with going long, far and uphill with
minimal burn-out) and another picture will have the saddle quite a bit
lower (suggesting I was riding very technical trails or trials-ish
stuff, and wanted to be able to grab the bike with my knees and/or dab
a foot easily). To help cut down on this confusion, I usually ask if
the person has any pics of themselves on the bike, when I'm asking for
their height and pant inseam. If I can get all that, I can usually
make a call (within reason). Even without the pic, if someone is 6"
taller or shorter than you, it's unlikely their bike will fit you,
unless it was very poor fit for them. That said, I got my MTB (which
fits me great) from someone 6" taller than me, who is a BMXer and
doesn't like anything resembling a proper fit. He in turn got it from
another guy who is, coincidentally enough, exactly my height & inseam,
and darn close on weight as well. We could be brothers based on size,
exchanged bikes and clothes for most of our teenage years, and the
frame was made for him. So I guess what I’m saying is even the height
thing can be a bust without knowing how that person sits on that bike,
which is why a pic of them on the bike and their height/inseam is my
preferred way to go.

Also, fit on a MTB is far less important than fit on a road bike. I’m
not saying it doesn’t matter, but it’s less important, which is
probably one of the reasons so many MTBs just come in sm, med, lg & xl
rather than cm increments. If it’s close enough, the details can be
dialed in as you ride.

On Nov 3, 11:13*am, " wrote:
On Nov 3, 10:51*am, Mike Rocket J Squirrel





wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

Personally, I'm not able to tell size by photos. *I've been in the
same situation you're in, however, and I find it easiest to ask the
person how tall they are, and what size pant inseam they wear. *Then
compare that to my own, look at the saddle height, and I can usually
guestimate if it's in my ballpark or not. *One problem with this
method is so many people ride with their saddles quite low, while
others ride with them at road-bike height, giving almost full leg
extension on the bottom of the pedal stroke. *Personally I adjust my
saddle to the ride, so in one picture it might be quite high
(suggesting I was riding trails that didn't really test my technical
ability, and was more concerned with going long, far and uphill with
minimal burn-out) and another picture will have the saddle quite a bit
lower (suggesting I was riding very technical trails or trials-ish
stuff, and wanted to be able to grab the bike with my knees and/or dab
a foot easily). *To help cut down on this confusion, I usually ask if
the person has any pics of themselves on the bike, when I'm asking for
their height and pant inseam. *If I can get all that, I can usually
make a call (within reason). *Even without the pic, if someone is 6"
taller or shorter than you, it's unlikely their bike will fit you,
unless it was *very poor fit for them. *That said, I got my MTB (which
fits me great) from someone 6" taller than me, who is a BMXer and
doesn't like anything resembling a proper fit. *He in turn got it from
another guy who is, coincidentally enough, exactly my height & inseam,
and darn close on weight as well. *We could be brothers based on size,
exchanged bikes and clothes for most of our teenage years, and the
frame was made for him. *So I guess what I’m saying is even the height
thing can be a bust without knowing how that person sits on that bike,
which is why a pic of them on the bike and their height/inseam is my
preferred way to go.

Also, fit on a MTB is far less important than fit on a road bike. *I’m
not saying it doesn’t matter, but it’s less important, which is
probably one of the reasons so many MTBs just come in sm, med, lg & xl
rather than cm increments. *If it’s close enough, the details can be
dialed in as you ride.- Hide quoted text -

- Show quoted text -

Of course I couldn't find a good shot of my bike with the saddle lower
to give an example, but it's in the bottom of this shot shown in it's
"in the middle" position, set up so I can ride for distance but still
dabble on the techinical stuff, jump a bit, etc. http://tinyurl.com/3xxufb

And here it is after powerline riding (to the right, snagged from a
beamshot angle from testing lights & lenses): http://tinyurl.com/6k4sbu

On Nov 3, 7:51*am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm

On Nov 3, 12:24*pm, pm wrote:
On Nov 3, 7:51*am, Mike Rocket J Squirrel





wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm- Hide quoted text -

- Show quoted text -

While it involves more work on your part than my idea, I like this
plan a lot. Especially if the seller isn't overly helpful providing
additional info & pics. Good thought, PM.

On Nov 3, 9:24*am, pm wrote:
On Nov 3, 7:51*am, Mike Rocket J Squirrel





wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm- Hide quoted text -

- Show quoted text -

I actually measured flange dimensions on a hub this way, using the OLD
of 135mm as the constant. The spokes I ordered at the same time as the
hub worked fine, much to my relief, and, honestly, surprise.

On 11/3/2008 9:24 AM pm wrote:

On Nov 3, 7:51 am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm

Very handy and obvious once explained. Since I know that my desired reach
should not exceed 24 inches (as measured per Dimension "B" the drawing at
http://socal2bend.blogspot.com/2008/...ain-bikes.html )

then the reach on the photo of a candidate bike should not be a whole lot
greater than the rim diameter of 559 mm, or 22 inches.

Using this method, I can see that the bike for sale at
http://bend.craigslist.org/bik/903343909.html has too much of a reach.


--
Mike "Rocket J Squirrel"
Bend, Oregon

On Nov 3, 2:15*pm, Mike Rocket J Squirrel
wrote:
On 11/3/2008 9:24 AM pm wrote:





On Nov 3, 7:51 am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm

Very handy and obvious once explained. Since I know that my desired reach
should not exceed 24 inches (as measured per Dimension "B" the drawing athttp://socal2bend.blogspot.com/2008/10/seeking-used-mountain-bikes.html)

then the reach on the photo of a candidate bike should not be a whole lot
greater than the rim diameter of 559 mm, or 22 inches.

Using this method, I can see that the bike for sale athttp://bend.craigslist.org/bik/903343909.htmlhas too much of a reach.

--
Mike "Rocket J Squirrel"
Bend, Oregon- Hide quoted text -

- Show quoted text -

I just checked out your page requesting bike measurements. With all
due respect, that does seem a bit involved to expect someone to do,
especially if they feel they have a good deal and their bike is going
to sell anyway (which are generally the bikes you want). There's also
plenty of room for error, as someone may not take "B" vertically, but
rather from seat to bars, which would add to the length.

Perhaps you could just ask for seat tupe and top tube lengths, C-C?
That way nobody has to adjust, measure, set, remeasure, etc. They can
grab a tape, pull a couple quick measurements and tell you the frame
size, and you can go from there.

Also, measurement B (which seems to be your primary concern, and IMO
rightfully so) can be adjusted quite a bit with a stem change. Stems
are cheap, especially online and/or used.

On Nov 3, 2:15*pm, Mike Rocket J Squirrel
wrote:
On 11/3/2008 9:24 AM pm wrote:





On Nov 3, 7:51 am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm

Very handy and obvious once explained. Since I know that my desired reach
should not exceed 24 inches (as measured per Dimension "B" the drawing athttp://socal2bend.blogspot.com/2008/10/seeking-used-mountain-bikes.html)

then the reach on the photo of a candidate bike should not be a whole lot
greater than the rim diameter of 559 mm, or 22 inches.

Using this method, I can see that the bike for sale athttp://bend.craigslist.org/bik/903343909.htmlhas too much of a reach.

--
Mike "Rocket J Squirrel"
Bend, Oregon- Hide quoted text -

- Show quoted text -

That bike didn't look that big to me, but using the aforementioned
method in my CAD software, I got a B dimension of almost 32", or 8"
more than you're looking for. Either that is a really big bike,
you're looking for a really small bike, or there's something off in
the measurement system somewhere.

On Nov 3, 3:03*pm, " wrote:
On Nov 3, 2:15*pm, Mike Rocket J Squirrel





wrote:
On 11/3/2008 9:24 AM pm wrote:

On Nov 3, 7:51 am, Mike Rocket J Squirrel
wrote:
Mrs Squirrel and I are in the market for small mtb (13'' works for her,
15'' is kind of my size), but when folk advertise their mtbs on the local
craigslist, they rarely mention the size. I email them about it, but more
often than not they say that the size isn't on the frame anywhere.

So I ask the seller to measure the bike per my blog entry he

http://socal2bend.blogspot.com/2008/...ain-bikes.html

But not all sellers are motivated to break out the old tape measure.

So before heading over to see the bike in person, it would be helpful for
me to eliminate those that are clearly too large.

While I've gotten pretty good at determining the size of a standard kind
of road frame by looking at a pictu the length of the seat stays are a
clue, as well as the length of the steering tube -- it's not foolproof but
I can generally see if the bike is a small one or not.

But I'm not clear whether one can make a call about mtb frames by looking
at the picture alone.

For example,

http://bend.craigslist.org/bik/903343909.html

--
Mike "Rocket J Squirrel"
Bend, Oregon

If you have a decently square-on side view, I've used a graphics
program that can tell the distance between two points, though you
could also just blow up the image and hold a ruler to your screen. You
know the rim is a standard size (559 mm), so you measure across the
rim, call it X, then measure the dimension you want, multiply by 559
mm and divide by X. This usually gets within an inch or so.

-pm

Very handy and obvious once explained. Since I know that my desired reach
should not exceed 24 inches (as measured per Dimension "B" the drawing athttp://socal2bend.blogspot.com/2008/10/seeking-used-mountain-bikes.html)

then the reach on the photo of a candidate bike should not be a whole lot
greater than the rim diameter of 559 mm, or 22 inches.

Using this method, I can see that the bike for sale athttp://bend.craigslist.org/bik/903343909.htmlhastoo much of a reach.

--
Mike "Rocket J Squirrel"
Bend, Oregon- Hide quoted text -

- Show quoted text -

That bike didn't look that big to me, but using the aforementioned
method in my CAD software, I got a B dimension of almost 32", or 8"
more than you're looking for. *Either that is a really big bike,
you're looking for a really small bike, or there's something off in
the measurement system somewhere.- Hide quoted text -

- Show quoted text -

Just tried the same method on my hardtail, although the bike is at a
bit of an angle to the cam so I expected skewed resutls. Got a B
dimension of 28.86, wiht the saddle higher than you would want it, and
a stem of average length - not a monster but not short either. I have
a feeling you're going to end up with a shorter stem. Just fussing
around here trying to find how your equation works out with our new
sizing method, but so far i'm really leaning toward asking for top
tube and seat tube dimensions. IMO top tube is more important, seat
heigth is easily adjusted.