Can I Put 140mm Forks on a 120mm Bike?

Can you Put 140mm Forks on a 120mm Bike? You’re a bike enthusiast and you have big plans for your next ride. But the fork on your current bike is 120mm. So you go to the store and find some 140mm forks, but what about those spacers?

This question can be very confusing if you don’t know what to consider in your decision-making process when choosing new components for your bicycle-frame setup.

You will want to take into consideration how much clearance there is between the fork stanchions and front tire as well as with brakes, shock absorber, and derailleur systems.

We have broken down the process of how to install 140mm forks on a 120mm bicycle.

Can I Put 140mm Forks on a 120mm Bike?

Yes, it is possible to put 140mm forks on a 120mm bike. This will increase the bike’s overall wheelbase and make it more stable at high speeds. However, it is important to make sure that the frame can handle the additional stress of the larger forks.

You can put a 140mm fork on a 120mm bike, but you will need to make sure that the fork is 20mm shorter than what you have currently. Many people have done this and had no issues, but it is important to check for sag before you commit.

It is also possible to put a 150mm fork on a 120mm bike. The main difference between a 100mm and 120mm fork is the travel. A 120mm bike can handle more fork travel than a 100mm bike. The sag for the rear shock should be 20% – 30%. The sag for the front fork should be 10%.

What is the difference between a 120mm fork and a 140mm fork?

The 120mm fork is smaller in diameter than the 140mm fork. This means that the 120mm fork is not compatible with a bike that has been designed for a 140mm fork. The 140mm fork has more travel than the 120mm fork.

Also Read: 120mm vs 140mm Travel Forks: Which is Right for You?

This means that it will provide more suspension and absorb more shock when riding over rough terrain. You can still put a 140mm fork on a 120mm bike, just ensure it is compatible with the frame of the bike.

How to install 140mm Forks on a 120mm Bike

  • Torque both bottom nuts to 50in-lb (5.7 Nm).
  • Use a 2mm hex wrench to install the red rebound knob. Make sure that the set screw lines up with the depression in the rebound adjuster shaft.
  • Clean the exterior of your fork.
  • Install the Lower Leg Assembly onto the upper tubes. Inject the appropriate amount of FOX 20wt. Gold oil into each leg through the bottom hole.

How do I know if my bike can accommodate a 140mm fork?

Most high-end forks come with mind-boggling adjustability. You can usually find a 140mm fork in the same brand as your 120mm bike. For example, Fox and RockShox are common brands that make both 120mm and 140mm forks.

Most bikes can accommodate a 140mm fork, but it may require modifications to the bike. The best way to know for sure is to consult your bike’s owner’s manual or contact the manufacturer directly.

Can you upgrade bike forks?

Yes, you can upgrade bike forks. Generally speaking, the more money you spend on an upgrade, the better the performance you will get.

However, there are many different features that you can choose from when upgrading your bike forks. If you have a bike that is only a few years old, it is likely that you can upgrade your bike forks without any problems.

Does increasing fork travel change head angle?

Increasing fork travel will change the head angle by 1°. This will make the bike feel more stable at high speeds and on rough terrain. However, it will also make the steering feel heavier and less responsive. If you are looking for a more agile and nimble bike, then you should stick with a 120mm fork.


So, can you put 140mm forks on a 120mm bike? Yes, but you need to be aware of a few things first. Make sure you know your frame geometry and that you have an integrated headset.

Once you have those things sorted, you’ll be able to enjoy the increased suspension travel on your bike. Thanks for reading and please subscribe to our mailing list for more great content like this.

Anna Stones