Bicycle Geometry Terms
99spokes.com
Bicycle Geometry Terms
1–10 of 78 posts
Re: Bicycle Geometry Terms
#2This site is fantastic !
The "compare" part is really great - with a little scatterplot price vs estimated spec level - I've used it massively when choosing my bike.
Re: Bicycle Geometry Terms
#3Do you think people who fix bikes or are bike enthusiasts know which of these components affect which aspect of riding? I can imagine knowing all the specific names for the parts is difficult but their affect on biking experience seems very relevant. Something that was not so obvious to me.
Re: Bicycle Geometry Terms
#4This site is fantastic ! The "compare" part is really great - with a little scatterplot price vs estimated spec level - I've used it massively when choosing my bike.
Very useful site, the geometry comparison amazing!
Re: Bicycle Geometry Terms
#5Do you think people who fix bikes or are bike enthusiasts know which of these components affect which aspect of riding? I can imagine knowing all the specific names for the parts is difficult but their affect on biking experience seems very relevant. Something that was not so obvious to me.
Anecdote:
My friends and I are avid mountain bikers, and semi-frequent road bikers and most of us have a pretty decent grasp on the effect of the main factors that will affect how a bike rides and handles and discussions are often had on the validity and suitability of different bikes geo choices for different kinds of riding. None of us are experts and we couldn’t tell you exactly how a bike would feel just by looking at the geometry, but you get a decent mental model after a while.
Re: Bicycle Geometry Terms
#6Do you think people who fix bikes or are bike enthusiasts know which of these components affect which aspect of riding? I can imagine knowing all the specific names for the parts is difficult but their affect on biking experience seems very relevant. Something that was not so obvious to me.
yes. most people probably haven't read a guide like this, but if you've ridden a good variety of bikes you get a sense for how the bb height affects stability, or how the head tube angle and the trail affect your steering.
some bikes even offer adjustable geometries by moving a bolt to a different position, which really makes it easy to understand how a change in geometry affects the handling characteristics.
Re: Bicycle Geometry Terms
#7Great explanations!
It’s really silly that seat tube length is used as the single measure of frame size. Much more important is reach and standover height, since those can’t easily be changed. A longer or shorter stem will adjust reach at the expense of changing how responsive the steering is, whereas a short seat tube can be fixed with a longer seat post. Seat tube length is also measured differently by different manufacturers — sometimes it’s center to center (of the tubes), sometimes center to top, etc. Seat tube length is convenient but it’s not what people should focus on when trying to find a bike that fits.
Re: Bicycle Geometry Terms
#8If you are interested in messing around with these settings and many more, look at the great parametric bicycle cad system “Bikecad”. Brett curry maintains and updates it for eons now. And crazy licensing — one time payment gets lifetime of updates.
Re: Bicycle Geometry Terms
#9Do you think people who fix bikes or are bike enthusiasts know which of these components affect which aspect of riding? I can imagine knowing all the specific names for the parts is difficult but their affect on biking experience seems very relevant. Something that was not so obvious to me.
There are professional "bike fitters" that know how to adjust all these things (those that can be adjusted) and more in such a way you get everything set up the best given your body and goals.
For instance, given a bike and a rider, one can adjust seat height, seat position, stem length, handlebarhheight, crank arm length and possible more things to get the correct reach and stem height. However, all that also has to be adjusted to account for body size (limb lengths), mobility etc, in order to level the hips, get the knees correctly over the pedals, aero position, correct weight on the hands, no chafing in the butt etc. It's really an art to adjust everything at once, as fixing one thing affects the others.
So while a bikefit can cost about $300, it's money well spent if one is serious about the biking (and one has then probably spent ~20x that on bike+gear anyways.. ). I'm about to head out for a ~120km ride today, so I've found a bike fit invaluable.
Re: Bicycle Geometry Terms
#10This is great.
One thing I do notice missing is the affect of stem length on steering, particularly for road bikes.
It’s not uncommon for road bikes to have both a steep head tube angle and a longer stem e.g. > 110mm to increase stability at speed.
Narrower and lower handlebars give you better aerodynamics but also affect both comfort and steering.