Nothing ruins the start of a bike trip like discovering at the airport that your bike doesn't fit in the bag you borrowed. Here's how to avoid that nightmare.
Why Compatibility Matters
Horror Story
"Showed up to Brisbane Airport with my XL Megatower and a borrowed bag. Couldn't get the frame in no matter what I tried. Ended up paying $200 for bubble wrap and prayers. Bike arrived with a cracked chainstay." — Actual rider who wishes they'd checked first.
Modern mountain bikes have grown dramatically. An XL 29er enduro bike today has a longer wheelbase than a downhill bike from 2015. Many travel bags were designed for smaller bikes.
Key numbers:
- Average trail bike wheelbase has increased 50-80mm since 2018
- XL 29ers now commonly exceed 1,300mm wheelbase
- Many "universal fit" bags max out at 1,250-1,270mm
Wheelbase Explained
What is Wheelbase?
Wheelbase is the horizontal distance between the centers of your front and rear axles. It's the primary measurement that determines if a bike fits in a travel bag.
How to Find Your Wheelbase
- Geometry chart (easiest): Look up your bike's geometry on the manufacturer's website. Find your frame size, then look for "wheelbase."
- Measure it: Place bike on flat ground, measure from front axle center to rear axle center. Use a long tape measure or string.
- PackMyRide database: Select your bike make/model/size and we'll pull the wheelbase from our geometry database.
Common Wheelbase Ranges
Other Fit Factors
Wheelbase is the main measurement, but other factors matter too:
Tire Size
A 29x2.6" tire takes up more space than a 27.5x2.4". Some bags have specific wheel pockets that won't accommodate plus-sized tires without deflating.
Handlebar Width
800mm bars are now common on enduro bikes. Some bags require you to remove or rotate bars to fit. Check the bag's internal width specification.
Fork Travel
Longer forks = longer bike when laid flat. A 180mm fork adds significant length compared to a 140mm fork. Some bags list "max fork travel" in specs.
Frame Size vs Wheelbase
Don't rely on frame size alone. A "Large" Santa Cruz Megatower has a longer wheelbase than an "XL" of many other brands. Always check actual wheelbase.
How PackMyRide Compatibility Works
We've built a database of bike geometry from major manufacturers. When you search for a bag:
Our Matching System
- Select your bike make, model, year, and size
- We pull your wheelbase from our database
- We filter to show only bags that fit your bike
- Green badge = guaranteed fit, yellow = should fit, red = won't fit
No more guessing. No more horror stories. Just bags that actually fit your bike.
Borderline Cases
What if You're 1-2cm Over?
Soft bags have some flex. If your wheelbase is 1-2cm over the stated max, you can often make it work by:
- Removing the front wheel completely (not just loosening)
- Rotating handlebars aggressively
- Using a shorter stem (temporary swap)
- Letting some air out of fork (reduces compressed length)
Borderline = Risk
We mark borderline fits with a yellow badge. It'll probably work, but test at home before the airport. Don't be the person discovering fit issues at check-in.
When to Size Up
If you're borderline, consider:
- Renting a hard case (more forgiving on dimensions)
- Choosing a bag with stated XL/long-wheelbase compatibility
- Asking the owner if they've packed similar-sized bikes
Check Your Bike
Ready to find a bag that fits? Use our AI-powered search to describe your bike and we'll match you with compatible bags in your area.
Tell us what bike you ride and we'll show you compatible bags.
Check compatibilityDon't Know Your Bike's Geometry?
Try these resources:
- Geometry Geeks: geometrygeeks.bike — comprehensive database
- Manufacturer website: Look under "specs" or "geometry"
- Your receipt/manual: Often includes frame size specs
- Measure it: Tape measure, flat ground, axle to axle