Got questions about what VYNL frame size to choose? We’re here to help with sizing guidelines. We lean to Colby Pearce of Pearce Coaching and Fitting in Boulder, CO for fitting advice. We have absolute trust in Colby for all our bike fit needs. Colby has been fitting athletes since 2012, plus he’s an absolute shredder on the track bike.

Start with reach and stack

Colby suggests that we focus on the reach and stack dimensions when sizing a frame as they are the best way to compare apples to apples. Stack and reach normalize the dimensions by referencing the top of the center of the head tube in both the X and Y axis. 

Reach is the X axis, or vertical measurement from the center of the bottom bracket to the top of the center of the head tube. Consider reach to be a measure of your body to the handlebars.

Stack is the Y axis, or horizontal measure from the center of the bottom bracket to the middle of the head tube. Consider stack a measure of the bike’s height.

Colby points out some of the nuances you should be aware of when comparing reach and stack. Key measurements of bike parts are not captured in reach and stack, such as bar drop and reach, headset dimensions and stem length. At the same time, your choice of bars, stem length, crank length and saddle shape can help dial in the fit of your VYNL for your physiology and riding demands.

Compare our geo charts

First, consider your riding position on your current bike as well as your riding goals and style. You can decide if you’d like to replicate this position or go more aggressive, i.e. additional reach and lower stack. Next, find your current bike’s geometry chart with a search on the manufacturer’s website. Now, compare the reach and stack of your current bike to the VYNL Bikes geometry charts, or use the nifty tool provide by Bike Insights. The charts can be found below or individually by clicking to Road Rim, Road Disc or Gravel Disc.

As noted above, reach and stack are normalized measurements that can be compared from manufacturer to manufacturer. In some cases, you may find that the VYNL geometries have a lower stack and longer reach than your current ride due to our race-bred geometry, resulting in a more aggressive position.

Professional fitters know best

A qualified and experienced bike fitter is the best way to determine your optimal frame size. One appointment with a fitter will provide meaningful information and education for future bike purchases, changes to components and riding position. At your first fitting appointment, you can expect an evaluation of your riding goals, physiology, range of motion, pedal competency, breathing function and more. Colby suggests a bike fit every year as the body is always changing and the bike fit should reflect this evolution.

Looking for IRL bike fit help? If you’re in the Boulder area, then we suggest an appointment with our guy Colby at Pearce Coaching and Fitting. The International Bike Fitting Institute is a great resource for finding a qualified bike fitter near you by using the “find a fitter” tool. Still looking for help? Shoot us an email and we can help you with your sizing questions.