A BionX system will fit on most bikes and it' easy to determine if it will fit on yours. Some quick facts:
Wheel Size: The BionX works with 20", 24", 26", 700c and 29er wheels. To determine your bike's wheel size, look for some numbers printed onto the sidewall of your tire. On one side of the tire there should be a set of numbers something likes this: "26 x 1.5" or "700 x 35." The first number is the size of the wheel. 700c and 29er will use the same size BionX motor as they are in fact the same size.
Drivetrain Compatibility: The BionX is usable in the REAR wheel only. So, first take a look at your rear wheel. Does it have external gears or internal gears? Is it a single speed bike (just 1 gear)? BionX will not work with internal gears or single speed bikes. If you have multiple external gears you're all set!.
The BionX requires a width of 135 mm or 5.3 inches. Steel frames can flex a bit to accommodate a difference of 5mm or .2 inches. Aluminum, titanium, and carbon frames cannot flex much and have to be exact.
Take a look at some of the wiring diagrams below to check what will work best for your bike. Then use this guide to check if you'll need any extra extension cables.
Motor cable: Measure the distance (along frame) from where the rear of battery bracket will be to rear axle (on non-drive side of bike). Follow your brake or shifter cables for cleanest cable routing. The BionX default measurement for Motor to Battery cable is 23 inches.
Console (display) cable: Measure distance (along frame) from where the rear of battery bracket will be to where the console will be on the handlebars. Follow your brake or shifter cables for cleanest cable routing. The BionX default measurement for Console to Battery cable is 47 inches.
BionX cable extensions can be purchased and strung together in a chain to meet your needs:
There are two types of battery: "rear rack" or "down tube". The down tube battery typically goes where your water bottle goes whereas the rear rack battery slides into BionX's own proprietary rear rack. Some very small frames or frames with special shapes are too tight to fit a down tube battery. Take a minute or two to measure your frame if it looks like it might be an issue.
For 90% of BionX installations you can just use the hardware included with the kit. For some special situations you may need a more customizable way to mount the battery. Hose clamps work great and can be threaded right through the battery rail. This works especially well on recumbents where you don't find standard bicycle geometry.