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OccasionalFlyer
December 14th 11, 09:04 PM
I know this isn't a racing question per se, but I didn't see a
newsgroup that looked more appropriate. I'm shopping for a new road
bike, and am considering a Trek Madone, Cannondale Synapse or
Supersix, or Cervelo (like an R3). I'cw having a little trouble with
this. Cannondale and Cervelo both seem to have frame sizes of 51 and
54 but nothing in-between. My current road bike is 52cm and that feels
right. I've tried both the 51' with the seat raised and the 54' with
the seat lowered. The person at the bike store who worked with me
didn't really seem able to say, "You can tell if it's the right frame
size if..." The 54' is too tall, even with the seat lowered, while
the 51' feels a bit too cramped. I know that comfort (since I'm not
trying to race any more) is important but there are multiple
adjustments that could be made, like stem height, to make the right
sized frame feel more comfortable. Is there any good technique beyond
standing over the top tube and assessing how much space there is
between the bike and the rider to determine if I'm choosing the right
frame size? There are probably bike shops where I could get more help
with this but I haven't found any yet in my area. Thanks.

Ken

Fredmaster of Brainerd
December 14th 11, 10:41 PM
On Dec 14, 2:04*pm, OccasionalFlyer > wrote:
> I know this isn't a racing question per se, but I didn't see a
> newsgroup that looked more appropriate. *I'm shopping for a new road
> bike, and am considering a Trek Madone, Cannondale Synapse or
> Supersix, or Cervelo (like an R3). *I'cw having a little trouble with
> this. *Cannondale and Cervelo both seem to have frame sizes of 51 and
> 54 but nothing in-between. My current road bike is 52cm and that feels
> right. *I've tried both the 51' with the seat raised and the 54' with
> the seat lowered. *The person at the bike store who worked with me
> didn't really seem able to say, "You can tell if it's the right frame
> size if..." *The 54' is too tall, even with the seat lowered, while
> the 51' feels a bit too cramped. *I know that comfort (since I'm not
> trying to race any more) is important but there are multiple
> adjustments that could be made, like stem height, to make the right
> sized frame feel more comfortable. *Is there any good technique beyond
> standing over the top tube and assessing how much space there is
> between the bike and the rider to determine if I'm choosing the right
> frame size? *There are probably bike shops where I could get more help
> with this but I haven't found any yet in my area. *Thanks.
>
> Ken

Find a bike shop that doesn't size frames by standover height.
That's irrelevant.

Measure the TOP tube length of your existing bike (and the stem
length) and compare to the spec of bikes you are trying out.

Is there a fit problem with your existing bike that you are trying
to rectify? If not, you can try to make the new bike duplicate
the old position. In any case the main variables you should be
looking at are saddle to bottom bracket distance (adjustable),
saddle to bars reach (depends on length of top tube), and
saddle to bar drop (depends on how much you raised the seat).
The latter two can be adjusted by changing the stem length
and angle, but if you have to do anything unusual with the
stem, it's typically a sign the frame doesn't fit.

Don't forget that as a Fat Master you often don't want or
can't fit a saddle-bar drop as large as you may have been able
to tolerate when you were young and beautiful (Jobst Brandt's
phrase).

I would scold you to ask this on rec.bicycles.tech (or search
the archives) but I don't think they ride over there any more.

Fredmaster Ben

Michael Press
December 14th 11, 10:42 PM
In article
>,
OccasionalFlyer > wrote:

> I know this isn't a racing question per se, but I didn't see a
> newsgroup that looked more appropriate. I'm shopping for a new road
> bike, and am considering a Trek Madone, Cannondale Synapse or
> Supersix, or Cervelo (like an R3). I'cw having a little trouble with
> this. Cannondale and Cervelo both seem to have frame sizes of 51 and
> 54 but nothing in-between. My current road bike is 52cm and that feels
> right. I've tried both the 51' with the seat raised and the 54' with
> the seat lowered. The person at the bike store who worked with me
> didn't really seem able to say, "You can tell if it's the right frame
> size if..." The 54' is too tall, even with the seat lowered, while
> the 51' feels a bit too cramped. I know that comfort (since I'm not
> trying to race any more) is important but there are multiple
> adjustments that could be made, like stem height, to make the right
> sized frame feel more comfortable. Is there any good technique beyond
> standing over the top tube and assessing how much space there is
> between the bike and the rider to determine if I'm choosing the right
> frame size? There are probably bike shops where I could get more help
> with this but I haven't found any yet in my area. Thanks.

As with all of usenet, there are blowhards and
biased views on rec.bicycles.tech. Nevertheless
it is a good place to ask.

Fitting a bicycle is complicated. Depends on
your physique including strength; flexibility;
will to adopt a full racing posture; and
relative lengths of arms, torso, inseam,
femur, and calf.

Stand over height is totally irrelevant.
You need your weight over the pedals so
that when pedaling resolutely you are not
forcing yourself forward or backward.
Once that is set you fit the top tube.
Longer is better up to a point. Then
you fine adjust with the stem length,
bar height, saddle height, saddle set-back,
and saddle angle; changing each very slightly
one at a time.

--
Michael Press

--D-y
December 15th 11, 03:58 AM
On Dec 14, 3:04*pm, OccasionalFlyer > wrote:
> I know this isn't a racing question per se, but I didn't see a
> newsgroup that looked more appropriate. *I'm shopping for a new road
> bike, and am considering a Trek Madone, Cannondale Synapse or
> Supersix, or Cervelo (like an R3). *I'cw having a little trouble with
> this. *Cannondale and Cervelo both seem to have frame sizes of 51 and
> 54 but nothing in-between. My current road bike is 52cm and that feels
> right. *I've tried both the 51' with the seat raised and the 54' with
> the seat lowered. *The person at the bike store who worked with me
> didn't really seem able to say, "You can tell if it's the right frame
> size if..." *The 54' is too tall, even with the seat lowered, while
> the 51' feels a bit too cramped. *I know that comfort (since I'm not
> trying to race any more) is important but there are multiple
> adjustments that could be made, like stem height, to make the right
> sized frame feel more comfortable. *Is there any good technique beyond
> standing over the top tube and assessing how much space there is
> between the bike and the rider to determine if I'm choosing the right
> frame size? *There are probably bike shops where I could get more help
> with this but I haven't found any yet in my area. *Thanks.

Ouch. What is your general location? Maybe someone here knows of a
real "pro" shop in your general area.
--D-y

OccasionalFlyer
December 15th 11, 05:45 AM
On Dec 14, 7:58*pm, --D-y > wrote:
> On Dec 14, 3:04*pm, OccasionalFlyer > wrote:
>
>
>
>
>
> > I know this isn't a racing question per se, but I didn't see a
> > newsgroup that looked more appropriate. *I'm shopping for a new road
> > bike, and am considering a Trek Madone, Cannondale Synapse or
> > Supersix, or Cervelo (like an R3). *I'cw having a little trouble with
> > this. *Cannondale and Cervelo both seem to have frame sizes of 51 and
> > 54 but nothing in-between. My current road bike is 52cm and that feels
> > right. *I've tried both the 51' with the seat raised and the 54' with
> > the seat lowered. *The person at the bike store who worked with me
> > didn't really seem able to say, "You can tell if it's the right frame
> > size if..." *The 54' is too tall, even with the seat lowered, while
> > the 51' feels a bit too cramped. *I know that comfort (since I'm not
> > trying to race any more) is important but there are multiple
> > adjustments that could be made, like stem height, to make the right
> > sized frame feel more comfortable. *Is there any good technique beyond
> > standing over the top tube and assessing how much space there is
> > between the bike and the rider to determine if I'm choosing the right
> > frame size? *There are probably bike shops where I could get more help
> > with this but I haven't found any yet in my area. *Thanks.
>
> Ouch. What is your general location? Maybe someone here knows of a
> real "pro" shop in your general area.
> --D-y- Hide quoted text -
>
> - Show quoted text -

San Gabriel Valley in southern California (between Pasadena and
Pomona). I sure miss the Bicycle OUtfiiter up in Los Altos. I used
to go there (and ride by there) a lot.

Steve Freides[_2_]
December 15th 11, 01:36 PM
OccasionalFlyer wrote:
> I know this isn't a racing question per se, but I didn't see a
> newsgroup that looked more appropriate. I'm shopping for a new road
> bike, and am considering a Trek Madone, Cannondale Synapse or
> Supersix, or Cervelo (like an R3). I'cw having a little trouble with
> this. Cannondale and Cervelo both seem to have frame sizes of 51 and
> 54 but nothing in-between. My current road bike is 52cm and that feels
> right. I've tried both the 51' with the seat raised and the 54' with
> the seat lowered. The person at the bike store who worked with me
> didn't really seem able to say, "You can tell if it's the right frame
> size if..." The 54' is too tall, even with the seat lowered, while
> the 51' feels a bit too cramped. I know that comfort (since I'm not
> trying to race any more) is important but there are multiple
> adjustments that could be made, like stem height, to make the right
> sized frame feel more comfortable. Is there any good technique beyond
> standing over the top tube and assessing how much space there is
> between the bike and the rider to determine if I'm choosing the right
> frame size? There are probably bike shops where I could get more help
> with this but I haven't found any yet in my area. Thanks.
>
> Ken

1. Why a new road bike? Just curious - is there anything that
component upgrades wouldn't fix on the frame you currently ride and, I
assume, are happy with?

2. Have you considered a frame that comes in a 52cm, even if it's not
on your current short list, just to see what another example of that
size feels like for you? You might find it's your current 52, and not
just any 52, that feels right.

3. Please note that what feels right is a slippery combination of
what's right and what you're used to - that's tough to sort out,
unfortunately.

4. For anything except a custom-made frame, there are likely to be
compromises, or at least adjustments, to be made. Ask the shop to fit a
longer stem on the 51cm frame if that's what you think it needs, or
perhaps an adjustable stem.

My own solution was to buy several used bikes in different sizes, fit
each with an adjustable stem, and ride each for at least a few months.
That's one way to sort out what you're used to from what might work
better for you. I did this not only with frame size but with crank
length, several handlebar dimensions, saddle position, cleat position,
etc., trying to ride everything enough to get used to it and then
compare. Not perfect, I realize, but I was very happy to have taken the
time to do it. Most everything I bought was relatively inexpensive. I
ended with my own "mix" - a custom frame because I finally figured out
they didn't make what worked best for me, heavy handlebars because they
were the size and shape I liked, I built my own wheels, etc., not to
mention cranks that didn't agree with the formula for my leg length by a
considerable amount. It's been 10-15 years since I did all that and
I'm still delighted to ride that bike.

Best of luck to you and hope the above is helpful in some small way.

-S-

--D-y
December 15th 11, 07:00 PM
On Dec 15, 7:36*am, "Steve Freides" > wrote:
> OccasionalFlyer wrote:
> > I know this isn't a racing question per se, but I didn't see a
> > newsgroup that looked more appropriate. *I'm shopping for a new road
> > bike, and am considering a Trek Madone, Cannondale Synapse or
> > Supersix, or Cervelo (like an R3). *I'cw having a little trouble with
> > this. *Cannondale and Cervelo both seem to have frame sizes of 51 and
> > 54 but nothing in-between. My current road bike is 52cm and that feels
> > right. *I've tried both the 51' with the seat raised and the 54' with
> > the seat lowered. *The person at the bike store who worked with me
> > didn't really seem able to say, "You can tell if it's the right frame
> > size if..." *The 54' is too tall, even with the seat lowered, while
> > the 51' feels a bit too cramped. *I know that comfort (since I'm not
> > trying to race any more) is important but there are multiple
> > adjustments that could be made, like stem height, to make the right
> > sized frame feel more comfortable. *Is there any good technique beyond
> > standing over the top tube and assessing how much space there is
> > between the bike and the rider to determine if I'm choosing the right
> > frame size? *There are probably bike shops where I could get more help
> > with this but I haven't found any yet in my area. *Thanks.
>
> > Ken
>
> 1. *Why a new road bike? *Just curious - is there anything that
> component upgrades wouldn't fix on the frame you currently ride and, I
> assume, are happy with?
>
> 2. *Have you considered a frame that comes in a 52cm, even if it's not
> on your current short list, just to see what another example of that
> size feels like for you? *You might find it's your current 52, and not
> just any 52, that feels right.
>
> 3. *Please note that what feels right is a slippery combination of
> what's right and what you're used to - that's tough to sort out,
> unfortunately.
>
> 4. *For anything except a custom-made frame, there are likely to be
> compromises, or at least adjustments, to be made. *Ask the shop to fit a
> longer stem on the 51cm frame if that's what you think it needs, or
> perhaps an adjustable stem.
>
> My own solution was to buy several used bikes in different sizes, fit
> each with an adjustable stem, and ride each for at least a few months.
> That's one way to sort out what you're used to from what might work
> better for you. *I did this not only with frame size but with crank
> length, several handlebar dimensions, saddle position, cleat position,
> etc., trying to ride everything enough to get used to it and then
> compare. *Not perfect, I realize, but I was very happy to have taken the
> time to do it. *Most everything I bought was relatively inexpensive. *I
> ended with my own "mix" - a custom frame because I finally figured out
> they didn't make what worked best for me, heavy handlebars because they
> were the size and shape I liked, I built my own wheels, etc., not to
> mention cranks that didn't agree with the formula for my leg length by a
> considerable amount. * It's been 10-15 years since I did all that and
> I'm still delighted to ride that bike.
>
> Best of luck to you and hope the above is helpful in some small way.

Or, Plan B: Find a good custom frame builder and get a bike meant to
fit you from the get-go.
This can be an expensive option but I know of one local custom maker
who has built for several very experienced riders in my cohort, to
universal praise and satisfaction.
Because that's what custom makers do, or are supposed to do, is build
you something that "fits" in every meaning of the word.

Or, maybe there is a shop with a "fit guru" who has successful
experience in making "off the rack" customers happy. Many people can
be happy with non-custom frame sizing, by (as above) choosing
seatposts, stems, crank length etc. to suit their choice of production
frame.

One thing, I saw "not racing"; you might be happier with a more
upright riding position than you've used previously. This is a big
factor in choosing among custom and production frames; you want
something (obviously, but...) that is comfortable and fun to ride, not
something that has to be aero and quite possibly less comfy.
--D-y

atriage[_6_]
December 15th 11, 07:59 PM
On 12/15/2011 07:00 PM, --D-y wrote:
> One thing, I saw "not racing"; you might be happier with a more
> upright riding position than you've used previously. This is a big
> factor in choosing among custom and production frames; you want
> something (obviously, but...) that is comfortable and fun to ride, not
> something that has to be aero and quite possibly less comfy.

A few times I've thought I'm old enough for a more upright position but
as soon as I've had to cycle into a headwind I've thought sod this and
gone back to a [semi] racing setup.

Steve Freides[_2_]
December 15th 11, 10:22 PM
--D-y wrote:

> Or, Plan B: Find a good custom frame builder and get a bike meant to
> fit you from the get-go.
> This can be an expensive option but I know of one local custom maker
> who has built for several very experienced riders in my cohort, to
> universal praise and satisfaction.
> Because that's what custom makers do, or are supposed to do, is build
> you something that "fits" in every meaning of the word.

Yeah, except that not everyone needs a custom frame. My saga was pretty
interesting, at least to me - I started with a frame with what was
supposed to be the right standover height, then kept trying bigger and
bigger frame until I had one I couldn't stand over even in cycling
shoes - I had to slide to one side to put a foot down - but I loved the
way it rode. The custom bike I eventually ordered had a top tube
several cm bigger than anything being produced in that size I could
find. (NB: Interestingly, some really old bikes fit me because there
was a time when they made one size of top tube for all frame sizes ...)

> Or, maybe there is a shop with a "fit guru" who has successful
> experience in making "off the rack" customers happy. Many people can
> be happy with non-custom frame sizing, by (as above) choosing
> seatposts, stems, crank length etc. to suit their choice of production
> frame.

Even that is risky business. The guy at my LBS is a real pro at fitting
people, but his suggestions just didn't and don't work for me.

> One thing, I saw "not racing"; you might be happier with a more
> upright riding position than you've used previously. This is a big
> factor in choosing among custom and production frames; you want
> something (obviously, but...) that is comfortable and fun to ride, not
> something that has to be aero and quite possibly less comfy.

+1 to that. Drop bar have different positions just for this purpose.
Find something that's comfortable for long distances on the tops and/or
hoods, and that you can really tuck into on the drops - that's proper
fit, IMHO.

-S-

Steve Freides[_2_]
December 15th 11, 10:23 PM
Steve Freides wrote:
> --D-y wrote:
>
>> Or, Plan B: Find a good custom frame builder and get a bike meant to
>> fit you from the get-go.
>> This can be an expensive option but I know of one local custom maker
>> who has built for several very experienced riders in my cohort, to
>> universal praise and satisfaction.
>> Because that's what custom makers do, or are supposed to do, is build
>> you something that "fits" in every meaning of the word.
>
> Yeah, except that not everyone needs a custom frame. My saga was
> pretty interesting, at least to me - I started with a frame with what
> was supposed to be the right standover height, then kept trying
> bigger and bigger frame until I had one I couldn't stand over even in
> cycling shoes - I had to slide to one side to put a foot down - but I
> loved the way it rode. The custom bike I eventually ordered had a
> top tube several cm bigger than anything being produced in that size
> I could find. (NB: Interestingly, some really old bikes fit me
> because there was a time when they made one size of top tube for all
> frame sizes ...)
>> Or, maybe there is a shop with a "fit guru" who has successful
>> experience in making "off the rack" customers happy. Many people can
>> be happy with non-custom frame sizing, by (as above) choosing
>> seatposts, stems, crank length etc. to suit their choice of
>> production frame.
>
> Even that is risky business. The guy at my LBS is a real pro at
> fitting people, but his suggestions just didn't and don't work for me.
>
>> One thing, I saw "not racing"; you might be happier with a more
>> upright riding position than you've used previously. This is a big
>> factor in choosing among custom and production frames; you want
>> something (obviously, but...) that is comfortable and fun to ride,
>> not something that has to be aero and quite possibly less comfy.
>
> +1 to that. Drop bar have different positions just for this purpose.
> Find something that's comfortable for long distances on the tops
> and/or hoods, and that you can really tuck into on the drops - that's
> proper fit, IMHO.
>
> -S-

Oops - the +1 is for the person who disagreed with you - sitting upright
in the wind is only OK if it's a "townie" bike, beach cruiser, etc. A
road bike means you want to be able to get reasonably aero somehow or
other.

-S-

--D-y
December 16th 11, 02:09 AM
On Dec 15, 4:22*pm, "Steve Freides" > wrote:

> Yeah, except that not everyone needs a custom frame.

Didn't say that. See the following paragraphs.

> *My saga was pretty
> interesting, at least to me - I started with a frame with what was
> supposed to be the right standover height, then kept trying bigger and
> bigger frame until I had one I couldn't stand over even in cycling
> shoes - I had to slide to one side to put a foot down - but I loved the
> way it rode. *The custom bike I eventually ordered had a top tube
> several cm bigger than anything being produced in that size I could
> find. *(NB: Interestingly, some really old bikes fit me because there
> was a time when they made one size of top tube for all frame sizes ...)

I am short in the legs and long in the TT to an extreme, myself.
Measured by people who measure people for bike fit <g>.
I used to be a toe-pointer (down) and rode a frame with a much taller
seat tube than I do now. Lots.
"Top tube length learning curve", BTDT.

Hence I comment when someone asks, especially someone who talks about
being "cramped" on a bike they can straddle the top tube of, while a
bike that needs the seat shoved (way?) down feels good to ride.

> > Or, maybe there is a shop with a "fit guru" who has successful
> > experience in making "off the rack" customers happy. Many people can
> > be happy with non-custom frame sizing, by (as above) choosing
> > seatposts, stems, crank length etc. to suit their choice of production
> > frame.
>
> Even that is risky business. *The guy at my LBS is a real pro at fitting
> people, but his suggestions just didn't and don't work for me.

I have had people tell me I didn't know what I was talking about when
I stated my bike fit measurements. Sometimes very rudely, and I've had
several experts tell me "That stem is way too long, that bike doesn't
fit you!" like I was committing a sin or something, and I learned to
respond: "It does now!!!" which is a pretty good response to that kind
of crap-ola. More BTDT, just sayin'.

> > One thing, I saw "not racing"; you might be happier with a more
> > upright riding position than you've used previously. This is a big
> > factor in choosing among custom and production frames; you want
> > something (obviously, but...) that is comfortable and fun to ride, not
> > something that has to be aero and quite possibly less comfy.
>
> +1 to that. *Drop bar have different positions just for this purpose.
> Find something that's comfortable for long distances on the tops and/or
> hoods, and that you can really tuck into on the drops - that's proper
> fit, IMHO.

If you can tuck without pain/injury, then you provide the position. If
tucking is bad, you have to adjust. BTDT, too.
--D-y

OccasionalFlyer
December 18th 11, 06:18 AM
On Dec 15, 5:36*am, "Steve Freides" > wrote:
> OccasionalFlyer wrote:
> > I know this isn't a racing question per se, but I didn't see a
> > newsgroup that looked more appropriate. *I'm shopping for a new road
> > bike, and am considering a Trek Madone, Cannondale Synapse or
> > Supersix, or Cervelo (like an R3). *I'cw having a little trouble with
> > this. *Cannondale and Cervelo both seem to have frame sizes of 51 and
> > 54 but nothing in-between. My current road bike is 52cm and that feels
> > right. *I've tried both the 51' with the seat raised and the 54' with
> > the seat lowered. *The person at the bike store who worked with me
> > didn't really seem able to say, "You can tell if it's the right frame
> > size if..." *The 54' is too tall, even with the seat lowered, while
> > the 51' feels a bit too cramped. *I know that comfort (since I'm not
> > trying to race any more) is important but there are multiple
> > adjustments that could be made, like stem height, to make the right
> > sized frame feel more comfortable. *Is there any good technique beyond
> > standing over the top tube and assessing how much space there is
> > between the bike and the rider to determine if I'm choosing the right
> > frame size? *There are probably bike shops where I could get more help
> > with this but I haven't found any yet in my area. *Thanks.
>
> > Ken
>
> 1. *Why a new road bike? *Just curious - is there anything that
> component upgrades wouldn't fix on the frame you currently ride and, I
> assume, are happy with?

Steve,

Thanks for the comments. I have a Trek 2100 that is about 20 years
old. It won't take all the upgrades that I want. Most significantly,
the frame is too narrow to accomodate today's 9 or 10 cog cassettes,
not to mention that the first bike I saw with combined brake levers-
shifters at the time was way out of reach financially. Adding this
after the fact, even if there was one for my frame, it would cost t so
much that I would probably save money on a whole bike. I am looking
to get better components than Shimano 105. That;s the basic reason.
I see this as probably my last road bike purchase (barring a massive
crash). If it lasts as long as the current one, I'll be dead by then!

Ken

Steve Freides[_2_]
December 18th 11, 01:13 PM
OccasionalFlyer wrote:

>> 1. Why a new road bike? Just curious - is there anything that
>> component upgrades wouldn't fix on the frame you currently ride and,
>> I assume, are happy with?
>
> Steve,
>
> Thanks for the comments. I have a Trek 2100 that is about 20 years
> old. It won't take all the upgrades that I want. Most significantly,
> the frame is too narrow to accomodate today's 9 or 10 cog cassettes,
> not to mention that the first bike I saw with combined brake levers-
> shifters at the time was way out of reach financially. Adding this
> after the fact, even if there was one for my frame, it would cost t so
> much that I would probably save money on a whole bike. I am looking
> to get better components than Shimano 105. That;s the basic reason.
> I see this as probably my last road bike purchase (barring a massive
> crash). If it lasts as long as the current one, I'll be dead by then!
>
> Ken

I wish you many happy miles on your new bike - enjoy!

-S-

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