Lots of MTBers know fat bikes as a way to keep their mountain biking going when there’s snow on the ground. But how are fat bikes to use on regular mountain bike trails during warmer seasons? Can they be used as an all around mountain bike? Read on to find out!
The difference between a trail bike and a fat bike
Fat bike:
Trail bike:
Let’s start off walking through some of the key differences between trail bikes (or regular mountain bikes) and fat bikes:
Tire width
The most obvious difference between a fat tire bike and a regular mountain bike is of course the width of the tires. Regular mountain bike tires usually fall in a range of about 2.2 inches to 2.5 inches in width.
Fat bikes, as their name implies, obviously have much wider tires and can vary quite a bit from around 3.7 inches up to 5.2 inches at the high end.
Tire pressure
By having bigger tires, fat tire bikes can operate with much lower tire pressure than ordinary mountain bikes, and can work with a wider range of tire pressures by comparison.
Fat bike tire pressure can range from around 5 PSI (pounds per square inch) all the way up to 30 PSI. Going as low as 5 PSI on a fat bike is usually reserved for riding in the snow or on otherwise slippery surfaces where you need to maximize your traction.
Regular mountain bike tire pressures usually range from as low as 16 PSI for lighter weight riders, and up to around 29 PSI.
Width between pedals
The width between your pedals, also known as stance width or Q factor, is another difference between ordinary mountain bikes and fat bikes. The typical stance width on a regular mountain bike is usually somewhere around 170mm.
For fat bikes, the stance width is usually a fair bit wider, often around 200mm or more. The wider stance width found on fat bikes works better for some riders than others.
Suspension
More and more it seems that regular mountain bike riders are gravitating towards full suspension mountain bikes. At minimum, just about every non-fat bike MTB will have at least a suspension fork in front (these bikes are known as hardtails).
Fat bikes have less suspension than regular mountain bikes, and the majority of fat bikes on the market are actually fully rigid, meaning they do not have either front or rear suspension. Some fat bikes offer a suspension fork in the front end for those wanting a little extra forgiveness in their fat bike.
Geometry
Compared to trail mountain bikes meant for a variety of terrain including downhill, fat bikes have slightly less slack (steeper) geometry.
This includes both the seat tube angle and head tube angle, which gives riders a feeling of being more on top of the front wheel compared to slacker trail bikes where the front wheel feels more out in front of you.
It makes sense that fat bikes have steeper geometry, because they are usually ridden at lower speeds. Having a steeper head tube angle especially helps bike handling and responsiveness when going slower, but the tradeoff is they can feel less stable and confident on fast descents.
Advantages of using a fat bike for regular trail riding
- Better traction than regular mountain bikes
- Fat tires result in a smooth ride
- Inspire confidence for newer riders
- Fat bikes can be more comfortable than traditional mountain bikes
- Can bring you places a regular mountain bike can’t
Because of the much larger tires on fat bikes, they have a larger contact patch with the ground compared to regular MTBs which gives them much better traction.
This is amplified even more if you ride your fat bike with lower tire pressure because it increases the contact patch of the tires even more.
By having more rubber gripping the ground at any time, fat tires make you much less likely to slip out while riding and this makes them well suited not only to snow, but all sorts of trails, including trails that are slippery because of being too dry and loose, wet, and trails with roots and other obstacles that can be slippery.
Fat bike tires also helps to promote a smooth riding experience. Despite fat bikes often not having any suspension, the tires on fat bikes do a great job at soaking up a lot of the bumps on the trails from things like rocks and roots.
Mountain bikers trying out a fat bike for the first time often expect a bumpier ride than they’re used to due to the fact that most fat bikes are fully rigid. This usually isn’t the case, and experienced riders giving fat bikes a try will often come away surprised by just how smooth they ride.
In particular, fat bikes excel over chunky terrain at slow to moderate speeds, soak up a lot of the bumps and plow over obstacles surprisingly well.
Because of their excellent traction and how smoothly they ride, fat bikes inspire confidence and this makes them a great choice for newer riders who are intimidated by mountain biking. Getting out on a fat bike can help new riders to see that what they previously thought to be scary can actually be a ton of fun.
The forgiveness of fat bikes allows new riders to make mistakes without major consequences. They don’t need to be perfect with their line choice because the fat tires absorb a lot of impacts, and they can lean harder into turns knowing they have superb traction.
Many people find that the smoother ride that results from fat bike tires together with the steeper geometry found on a fat bike makes it more comfortable to ride compared to a regular trail bike. While a fat bike is unlikely to be the first choice for a rider who wants to shred steep descents at high speed, it can be a much more comfortable ride for casual riders who want something both forgiving and fun.
Another major advantage fat bikes offer is their ability to go off the beaten path more than regular MTBs. Most people know that fat bikes are good for snow riding, but beyond that they can be brought on trails that wouldn’t be suitable for regular mountain bikes, which opens up a wider variety of places you can ride them. This is especially fun for the adventurers out there!
Disadvantages of using a fat bike for trail riding
- Heavier weight can make fat bikes feel sluggish compared to traditional MTBs
- Rolling resistance from the fat tires can make fat bikes less efficient
- Harder to transport compared to traditional mountain bikes
- Some riders experience hip and knee pain after riding a fat bike
Unfortunately, using a fat bike for regular mountain biking does come with disadvantages too.
If you want your bike to feel nimble and playful, a fat bike is probably not the best choice for you. Fat bikes are more tank than sports car, so if speed is what you’re after, it’s probably best to look for a trail bike or enduro bike.
Fat bikes are definitely on the heavier end of the spectrum when it comes to mountain bikes. They may not be significantly heavier than long travel enduro bikes, but they do still have some heft to them.
Beyond just their weight, the larger contact patch a fat bike’s tires have with the ground, while providing you with better traction, actually increases rolling resistance. The lower tire pressure you run for your fat bike, the more rolling resistance you’ll have. This can make a fat bike feel sluggish compared to regular mountain bikes.
Because of their size, fat bikes can be more difficult to transport compared to regular mountain bikes. Not all standard MTB bike racks will work for a fat bike, and even if they do, if you are transporting two bikes or more, fat bikes will make this more difficult due to the amount of space the bikes and fat tires take up.
Another possible disadvantage to fat bikes is that due to the wider stance width they have, some riders experience hip and knee pain from riding a fat bike. This obviously depends on your build and the stance width of your fat bike. Lots of fat bike riders never experience this pain. If you are someone who does have this issue with fat bikes, though, they may not be the ideal choice for your trail mountain bike rides.
Frequently asked questions
The disadvantages of riding a fat bike include its heavier weight and increased rolling resistance in its tires compared to regular MTB tires. The larger size of fat bikes can also make them difficult to transport as they won’t fit in all bike racks, and some fat bike riders can experience hip and knee pain resulting from the wider stance width of fat bikes compared to regular mountain bikes.
Yes, fat bikes can be used as mountain bikes, and many would consider them to be their own type of mountain bike. You can ride most of the same trails on a fat bike as you would on a regular MTB. For some trails and conditions, fat bikes will outperform regular mountain bikes thanks to their large tires which soak up bumps well and provide excellent traction. However, in terms of speed fat bikes are usually slower than regular mountain bikes.
Fat bikes are suitable for most mountain bike trails you could ride on an ordinary mountain bike. On regular, dry mountain bike trails they usually won’t be quite as fast as ordinary MTBs but that doesn’t mean they aren’t still fun to ride in these trails and conditions.
They’re also amazing in the snow and on slippery trails and can allow you to ride year round. They also are a great way to explore and can ride in places normal mountain bikes just don’t work, such as through fresh snow or even on the beach!
Conclusion
There you have it. While fat bikes won’t usually be outracing regular mountain bikes on dry trails, they can still be a lot of fun, and handle quite well on slow and moderate speed trails with chunky terrain. They are also a great option to build confidence on for newer riders thanks to how forgiving the fat tires are, both in absorbing bumps and in providing amazing traction.