Be honest – can you explain a word like “suspension sag” without looking it up?

I don’t blame you, though – it’s not easy. And there are more words related to motorcycle suspension that might leave you scratching your head.

But don’t worry – because in this blog post, you’ll discover the definition of 6 common (and sometimes confusing) motorcycle suspension terms.

Prefer to get this information in podcast form (as well as an overview about suspension)? Listen to the 30 Minute Motorcycling Podcast episode about suspension:

Term #1: Suspension travel

Suspension travel is the difference between fully decompressed front forks. Keep in mind, however, that a complete decompression is only possible when there’s no weight on the bike – including that of the rider.

Term #2: Suspension preload

The suspension preload is how much the suspension coil spring when it supports the bike’s weight – and ONLY the bike’s weight.

This means that if someone’s sitting on the bike, suspension preload does NOT apply.

Term #3: Sprung weight

The suspension supports several things on your bike, such as the engine, the frame, and the fuel tank (or battery for electric bikes).

The weight of everything the suspension supports is known as “sprung weight.” 

Term #4: Unsprung weight

Of course, the suspension can’t support everything, like the wheels and the tires. Everything that the suspension doesn’t support is called “unsprung weight.”  Typically, the less unsprung weight you have, the better.  Why? Because a bike with more unsprung weight takes longer to respond to bumps in the road.

Term #5: Spring rate

A coil spring needs a certain amount of weight to compress an entire inch (or 25 millimeters). The weight the spring needs to compress an entire inch is called the “spring rate.” The spring rate is measured in PSI or Newtons per Millimeters.

Term #6: Suspension sag

And finally, we get to the word I mentioned in the opening of this blog post – “suspension sag.” Suspension sag is how far the suspension compresses from a fully decompressed front fork. Sounds similar to suspension travel? Well, there’s a fundamental difference. Unlike suspension travel, suspension sag CAN take the rider’s weight into account – that’s why there’s a particular subcategory called “rider sag.”  

Learn more about suspension terms with the DWJ Motorcycle Terms and Biker Slang Dictionary

dwj motorcycle terms dictionary front cover
Want to dive deeper into suspension terms like “rebound dampening?” Or would you prefer to discover more about biker slang terms like:
  • “I did the ton”
  • “Highside”
  • “Streetfighter”
You can discover more about terms like these (and many more) in The Dual Wheel Journey Motorcycle Dictionary and Phrasebook.