Frame Comparison - Bar Curve X and Bar Top Y for Road Bikes

Frame Comparison - Bar Curve X and Bar Top Y for Road Bikes

In order to enhance the usefulness of our Frame Comparison tool we’ve added additional metrics that aid in precisely matching positions.
These metrics are Bar Curve X and Bar Top Y.
Bar Curve X and Bar Curve Y relative to bottom bracket
To calculate these metrics for road bikes we add the handlebar reach to the Handlebar X value. And the stack of the top of the handlebar to the Handlebar Y value.
Zooming in on the bars:
Bar Curve X and Bar Curve Y defined
It is important to note that the reach point on the bar curve is to the centre of the tube. And the stack point is to the highest point on the outer section of the bars near the hoods.
We’ve created these metrics for several reasons.
  1. To account for variations in bar design
  1. To make it easier for fitters to match positions

Variations in bar design

While there have long been variations on the classic Maes bar, we are starting to see a lot more variety in shapes, partially thanks to the rise in popularity of Gravel riding.
The Specialized Hover bar and BP4 bar are examples of opposite ends of the spectrum:
Specialized Hover BarSpecialized Hover Bar

BP4 BarBP4 Bar

The Specialized rises by 15mm while the BP4 drops by 54mm. This leads to a significant difference in the height of the hoods, for the same Bar XY. Or a significant difference in Bar XY if you wish to maintain the hood position.

Easier for fitters

It's extremely quick to compare different bar/stem combinations.

Frame Comparison screenshot showing selection of handlebarsFrame Comparison screenshot showing selection of handlebars

In the example above you can see that changing the bars for a rise option offers the possibility to reduce the spacer stack under the stem.

Frame Comparison screenshot with standard vs long-reach barFrame Comparison screenshot with standard vs long-reach bar


Why did we choose these points?

Bar XY is easy to understand because you measure from one point (centre of the BB) to another (centre of handlebar) in two dimensions. But there isn’t a reliable point to do this with on the bars.
Bar Top has the advantage of being easy to measure and not heavily affected by the inclination of the bars.
Bar Curve is also fairly easy to measure and can be calculated using information provided by most bar manufacturers.
The goal with these metrics is to define a useful approximation for the virtual intersection of the handlebar with the hoods. Going beyond the metrics we have defined would require knowing exact details of the handlebar bend and hood interface.

If you have any questions please contact us)

See also:
  1. Our free Frame Comparison tool
  1. A guide to Using Frame Comparison
  1. Using Bar XY Cartesian Coordinates
  1. Our Advanced Bike Finder tool

    • Related Articles

    • Using frame comparison

      The free velogicfit Frame Comparison tool offers a quick, fully-user-controlled way of comparing two or more frames side by side. You’ll find frame geometry, images (if available) and frame specifications. If you’ve got a target Bar X & Y (e.g. from ...
    • Using Bar XY Cartesian Coordinates

      Over the last few years it has become standard practice for bike manufacturers to provide Reach and Stack figures in their geometry charts. As shown below, these metrics give the coordinates of the top of the Head Tube relative to the Bottom Bracket. ...
    • Setting your location for find-a-fitter and Frame Comparison ads

      We're in business to help your business succeed. We want to help your potential customers find your service, and there are a couple of different ways we can do that. Find-a-fitter (all Velogic Studio users) Our public site has a "find-a-fitter" page, ...
    • Road metrics

      Our system offers an extensive range of metrics. Using 3D data well requires combining multiple factors in your decision making. Here is some guidance for "orthodox" positions.  Metric Range Ankle Angle Average 100-130, range < 30 Knee Angle Max ...
    • Taking bike measurements

      On the capture screen you will see a button for “MEASURE BIKE”: Clicking “MEASURE BIKE” will open the bike measurement popup window: Bike measurement window Follow the instructions on screen to use the wand to acquire the indicated points. Once you ...