Need help with Bike Sizing

I am going to purchase a K2 Zed 4.0, and I need help with sizing. I am 5'11/6'0 and weigh 170lbs. I
have a 30 inch inseam. I test rode a Medium once and it seemed small. Their geometry page is broken
down on their website for each bike. Here is the link to the Zed 4.0.

http://www.k2bikes.com/03products/mountain/zed_4.asp

What are the advantages of a large frame verses small frame, and how do you know if you have a
good bike fit.

Should I get a Medium or Large??

Thanks-- Jake

 

Jake-<< What are the advantages of a large frame verses small frame, and how do you know if you have
a good bike fit.

Should I get a Medium or Large??

A good bike fit is when somebody ensures your saddle is the right height, correct in terms of
fore-aft, the stem, top tube is correct. Standover means little, even less with compact. If the LBS
cannot do a sizing for you on the bikes you are looking at, go elsewhere...

Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
(303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

Thanks for the response, but I am ordering the bike, so unfortunately I don't have the
advantage of a LBS.

Jake

"Qui si parla Campagnolo" <[email protected]> wrote in message
news:[email protected]...
> Jake-<< What are the advantages of a large frame verses small frame, and
how do
> you know if you have a good bike fit.
>
> Should I get a Medium or Large??
>
> A good bike fit is when somebody ensures your saddle is the right height, correct in terms of
> fore-aft, the stem, top tube is correct. Standover
means
> little, even less with compact. If the LBS cannot do a sizing for you on
the
> bikes you are looking at, go elsewhere...
>
>
> Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
> (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

"Jake Barnes" <[email protected]> wrote in message
news:[email protected]...
> Thanks for the response, but I am ordering the bike, so unfortunately I don't have the advantage
> of a LBS.
>
> Jake
>
Sure you do. As long as you point out what you're doing, go ask your LBS to help. Since you're
probably going to have to have the bike worked on there, they should help out. If not, then try
another shop. Just make sure that you do buy things from the shop that helps out.

Mike

 

Thanks--

"Mike S." <[email protected]> wrote in message news:[email protected]...
>
> "Jake Barnes" <[email protected]> wrote in message
> news:[email protected]...
> > Thanks for the response, but I am ordering the bike, so unfortunately I don't have the advantage
> > of a LBS.
> >
> > Jake
> >
> Sure you do. As long as you point out what you're doing, go ask your LBS
to
> help. Since you're probably going to have to have the bike worked on
there,
> they should help out. If not, then try another shop. Just make sure that you do buy things from
> the shop that helps out.
>
> Mike

 

> Thanks for the response, but I am ordering the bike, so unfortunately I don't have the advantage
> of a LBS.

No way to get the bike locally? For sizing, that's a big issue, since it's not always a static
issue... sometimes you need to play around with things a bit, particularly with a mountain bike, and
get feedback after the bike's been ridden off-road. Many shops will even swap stems out after you've
already purchased the bike.

If you're familiar with the mechanics of a bike, obviously that will be of great help, but otherwise
you're also looking at dealing with assembly issues and taking care of the little things that
inevitably go wrong as things settle down. Plus warranty stuff... that could be a nightmare without
a shop to take care of things, and mountain bikes *do* have warranty issues from time to time,
sometimes significant ones (mostly having to do with forks, sometimes with incompatible drive-train
components and I note that they do mix & match a bit on that bike).

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

"Jake Barnes" <[email protected]> wrote in message
news:[email protected]...
> Thanks for the response, but I am ordering the bike, so unfortunately I don't have the advantage
> of a LBS.
>
> Jake
>
>
>
> "Qui si parla Campagnolo" <[email protected]> wrote in message
> news:[email protected]...
> > Jake-<< What are the advantages of a large frame verses small frame, and
> how do
> > you know if you have a good bike fit.
> >
> > Should I get a Medium or Large??
> >
> > A good bike fit is when somebody ensures your saddle is the right
height,
> > correct in terms of fore-aft, the stem, top tube is correct. Standover
> means
> > little, even less with compact. If the LBS cannot do a sizing for you on
> the
> > bikes you are looking at, go elsewhere...
> >
> >
> > Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
> > (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

 

[email protected] (Qui si parla Campagnolo) wrote in message
news:<[email protected]>...
> Jake-<< What are the advantages of a large frame verses small frame, and how do you know if you
> have a good bike fit.
>
> Should I get a Medium or Large??
>
> A good bike fit is when somebody ensures your saddle is the right height, correct in terms of
> fore-aft, the stem, top tube is correct. Standover means little, even less with compact. If the
> LBS cannot do a sizing for you on the bikes you are looking at, go elsewhere...
>
>
> Peter Chisholm Vecchio's Bicicletteria 1833 Pearl St. Boulder, CO, 80302
> (303)440-3535 http://www.vecchios.com "Ruote convenzionali costruite eccezionalmente bene"

Thank you for that Peter. Standover means little of you can get the rest right.

 

Spacey Spade <[email protected]> wrote:

>I've got a question about fit too. If you get to choose the top tube length, is it better to have a
>longer or shorter stem? (or what size stem is best for you?). Does the stem aid in cornering,
>leaning the rider into the turn?

It varies by the size and geometry of the bike, and affects the handling and "feel" of the bike as
the handlebars are moved relative to the front tire's contact point.

However, for "normal geometry" (the vast majority of road bikes) an "ideal stem" for a 50cm
bike would be in the 9cm range, a 56cm would be around 11cm, and a 62 would be best with a 13cm
or so stem.

Obviously these aren't rules, and there are a lot of variables. But that should give you a
starting point.

Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

> However, for "normal geometry" (the vast majority of road bikes) an "ideal stem" for a 50cm
> bike would be in the 9cm range, a 56cm would be around 11cm, and a 62 would be best with a 13cm
> or so stem.
>
> Obviously these aren't rules, and there are a lot of variables. But that should give you a
> starting point.

Thank goodness they're *not* rules! My two racing bikes, each 60cm, had very different top tubes,
such that one required an 8cm stem while the other a 12cm. The bike that takes the 8cm stem rode
every bit as nicely (actually, much better) than the bike with the 12cm stem, in terms of climbing,
cornering and handling in general. However, I had no trouble riding either bike in just about any
circumstance. I don't think there's even a rough generalization about "proper" stem length you can
make, other than to think, if a given bike requires a stem at one extreme or the other, it could be
an indication that a different size frame might be in order.

By the way, most of our shorter customers (those on 50cm bikes) tend towards shorter stems than 9cm.
This is largely due to top tubes that, on smaller bikes in general, are limited in how short they
can be due to wheel/foot clearance issues. 54cm frames (talking center to top here) are generally
where dimensions require fewer compromises, although I really don't see short stems as a compromise,
but rather a solution that works.

--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com

"Mark Hickey" <[email protected]> wrote in message
news:[email protected]...
> Spacey Spade <[email protected]> wrote:
>
> >I've got a question about fit too. If you get to choose the top tube length, is it better to have
> >a longer or shorter stem? (or what size stem is best for you?). Does the stem aid in cornering,
> >leaning the rider
into
> >the turn?
>
> It varies by the size and geometry of the bike, and affects the handling and "feel" of the bike as
> the handlebars are moved relative to the front tire's contact point.
>
> However, for "normal geometry" (the vast majority of road bikes) an "ideal stem" for a 50cm
> bike would be in the 9cm range, a 56cm would be around 11cm, and a 62 would be best with a 13cm
> or so stem.
>
> Obviously these aren't rules, and there are a lot of variables. But that should give you a
> starting point.
>
> Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

"Mike Jacoubowsky" <[email protected]> wrote:

>> However, for "normal geometry" (the vast majority of road bikes) an "ideal stem" for a 50cm
>> bike would be in the 9cm range, a 56cm would be around 11cm, and a 62 would be best with a 13cm
>> or so stem.
>>
>> Obviously these aren't rules, and there are a lot of variables. But that should give you a
>> starting point.
>
>Thank goodness they're *not* rules! My two racing bikes, each 60cm, had very different top tubes,
>such that one required an 8cm stem while the other a 12cm. The bike that takes the 8cm stem rode
>every bit as nicely (actually, much better) than the bike with the 12cm stem, in terms of climbing,
>cornering and handling in general. However, I had no trouble riding either bike in just about any
>circumstance. I don't think there's even a rough generalization about "proper" stem length you can
>make, other than to think, if a given bike requires a stem at one extreme or the other, it could be
>an indication that a different size frame might be in order.

Good catch - one of the things I meant to say (blame it on my brain bruise) is that there's less of
a negative impact to a shorter than "normal" stem than there is from going longer. As the brake
hoods inch out over the front tire's contact patch, the handling starts to get "odd". But there's
really very little down side to a shorter stem on most bikes.

Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

>By the way, most of our shorter customers (those on 50cm bikes) tend towards shorter stems than
>9cm. This is largely due to top tubes that, on smaller bikes in general, are limited in how short
>they can be due to wheel/foot clearance issues. 54cm frames (talking center to top here) are
>generally where dimensions require fewer compromises, although I really don't see short stems as a
>compromise, but rather a solution that works.
>
>--Mike-- Chain Reaction Bicycles http://www.ChainReactionBicycles.com
>
>
>"Mark Hickey" <[email protected]> wrote in message
>news:[email protected]...
>> Spacey Spade <spaceyg[email protected]> wrote:
>>
>> >I've got a question about fit too. If you get to choose the top tube length, is it better to
>> >have a longer or shorter stem? (or what size stem is best for you?). Does the stem aid in
>> >cornering, leaning the rider
>into
>> >the turn?
>>
>> It varies by the size and geometry of the bike, and affects the handling and "feel" of the bike
>> as the handlebars are moved relative to the front tire's contact point.
>>
>> However, for "normal geometry" (the vast majority of road bikes) an "ideal stem" for a 50cm
>> bike would be in the 9cm range, a 56cm would be around 11cm, and a 62 would be best with a 13cm
>> or so stem.
>>
>> Obviously these aren't rules, and there are a lot of variables. But that should give you a
>> starting point.
>>
>> Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

"Mark Hickey" <[email protected]> wrote in message
news:[email protected]...

> Good catch - one of the things I meant to say (blame it on
my brain
> bruise) is that there's less of a negative impact to a
shorter than
> "normal" stem than there is from going longer. As the
brake hoods
> inch out over the front tire's contact patch, the handling
starts to
> get "odd". But there's really very little down side to a
shorter stem
> on most bikes.

Mark, what do you think about going up a size (or two) and using a shorter than normal stem? For one
thing, I think a longer wheelbase is better, but long wheelbase bikes are often touring designs with
sluggish handling. Two, it seems like it might make standing/sprinting more flail-proof, not being
so much over the front wheel. So while I might normally ride a bike with a 58cm top tube and a 120mm
stem, how about a 60cm top tube and a 100mm stem? Or would it even make a difference?

Matt O.

 

"Matt O'Toole" <[email protected]> wrote:

>Mark, what do you think about going up a size (or two) and using a shorter than normal stem? For
>one thing, I think a longer wheelbase is better, but long wheelbase bikes are often touring designs
>with sluggish handling. Two, it seems like it might make standing/sprinting more flail-proof, not
>being so much over the front wheel. So while I might normally ride a bike with a 58cm top tube and
>a 120mm stem, how about a 60cm top tube and a 100mm stem? Or would it even make a difference?

It would give you a little less tendency toward wheel flop when climbing out of the saddle - not
a huge difference though, since both would be in a pretty "nominal range" of the stem for that
size bike.

It gets to be more of an issue as the stem length relative to the top tube goes up. For example, I
have two road bikes with similar overall fit. One is a 56cm c-t frame with a 56cm top tube and 11cm
stem, the other is a 54cm fixie with a 54.5cm top tube and 12cm stem (making it .5cm shorter). Both
handle very well, but the 56x11 beats the
54.5x12 hands down in climbing out of the saddle - not so much because the 54cm bike climbs badly,
but the 56cm bike is "just right".

The change in wheelbase would only be a couple cm max, so it's doubtful that in and of itself would
make a big difference in handling. The "tiller length" of the stem will make more difference IMHO
(as it does with my two bikes above, since the 54cm frame feels more "sluggish").

Mark Hickey Habanero Cycles http://www.habcycles.com Home of the $695 ti frame

 

"Matt O'Toole" <[email protected]> wrote in message
news:[email protected]...
>
> "Mark Hickey" <[email protected]> wrote in message
> news:[email protected]...
>
> > Good catch - one of the things I meant to say (blame it on
> my brain
> > bruise) is that there's less of a negative impact to a
> shorter than
> > "normal" stem than there is from going longer. As the
> brake hoods
> > inch out over the front tire's contact patch, the handling
> starts to
> > get "odd". But there's really very little down side to a
> shorter stem
> > on most bikes.
>
> Mark, what do you think about going up a size (or two) and using a shorter than normal stem? For
> one thing, I think a longer wheelbase is better, but long wheelbase bikes are often touring
> designs with sluggish handling. Two, it seems like it might make standing/sprinting more
> flail-proof, not being so much over the front wheel. So while I might normally ride a bike with a
> 58cm top tube and a 120mm stem, how about a 60cm top tube and a 100mm stem? Or would it even make
> a difference?

If you don't mind me butting in ... I use this approach often with alot of folks, and certainly for
folks who don't or won't afford a custom geo bike. The larger size allows the bars to get closer to
the saddle height. This allows people to not be inclined to use straight bars on road bikes! ;-)

--
Robin Hubert <[email protected]