Cut Steerer Tube Too Short? (Here’s What To Do)

An important part of bike fit is adjusting your handlebar height by cutting the steerer tube on your bike fork.

But what happens when you cut steerer tube too short? 

Is your fork ruined? Can you still adjust your handlebar height? 

This common mistake can be fixed, but there are limits. 

In this article, I’ll go over what to do if you cut steerer tube too short. I”ll also talk about how short it should be, and the consequences of cutting it too short.

How Short is Too Short?

The steerer tube on your bike fork extends up into the frame and allows you to attach and adjust your stem and handlebars. 

Also Read: Should I Cut Down My Steerer Tube?

How Short is Too Short When Cutting A Steerer Tube

A general rule of thumb is to leave at least 25mm – 30mm of the steerer tube extending above your stem. This gives enough room to attach your stem and spacers properly.

Cutting the steerer tube any shorter than 30mm above the stem risks not having enough space to properly attach and adjust your bike’s cockpit. 

You may be left with limited stem attachment options and insufficient spacer stack height to achieve your ideal handlebar position.

It’s even better to leave an extra 10-20mm to allow for adjustments later on. You can always cut it shorter if needed, but you can’t add length back!

Can You Still Use Fork With Steerer Tube Cut Too Short?

In some situations you may still be able to safely use your bike fork even if the steerer tube is cut a bit too short. But your attachment options will be limited. 

Here are some tips:

Get a Stem with Lower Stack Height

Using a stem with a lower overall stack height can allow it to be safely attached. 

Just make sure minimum insertion is achieved.

Use Fewer or No Spacers

You may have to sacrifice some spacer stack height above or below the stem. This may limit fit adjustability but allow stem attachment.

Adjust Riding Position

Moving your saddle forward and tilting down slightly can help compensate for having a lower handlebar position. 

Not ideal but a usable temporary option.

Also Read: Cracked Head Tube

However, if the tube was cut extremely short, you may have no safe way to attach both your stem and adjust handlebar height. 

At that point replacing the fork may be your only option.

What To Do If You Cut Steerer Tube Too Short

Here’s what you can do if steerer tube is slightly too short but you wanna avoid a new fork:

Use A Steerer Tube Extender

If you’ve cut your steerer tube a bit too short, using a steerer tube extender is often the easiest and quickest fix. 

Steerer tube extenders are inexpensive spacer-like devices that fit between the top of the steerer tube and the stem. 

Adding an extender effectively lengthens the steerer tube, allowing you to achieve the proper handlebar height. 

These extenders come in various lengths, so you can get your fit just right.

Milling Down The Head Tube 

If an extender alone can’t give you the height you need, another option is to mill down the head tube on the frame. 

This literally shortens the head tube to lower the stem and bars. 

A machine shop can carefully shave off just enough material to gain the required spacer height. 

The process is inexpensive but will permanently alter the frame.

Brazing On A New Steerer

A new section of steerer tube can also be brazed onto the old one. 

A skilled frame builder can cut off the too-short steerer and braze on a new extension piece to get the steerer back to the proper length. 

This approach is more complex and costly than using an extender but allows you to retain the original fork.

Replace the Fork

If the steerer is cut way too short, the simplest and the most recommended option is to replace the entire fork.

This is also the safest option, especially if you are unsure about using a steerer tube extender.

Fork manufacturers offer many models with steerer tube lengths to fit any bike. 

Consequences of Cutting the Steerer Tube Too Short

Cutting your steerer tube too short can have a few negative consequences:

Unable to Properly Attach Stem & Spacers: If cut too short, you may not have enough room left to attach your stem and spacers. Your minimum stem insertion line might no longer be achievable.

Lost Adjustability: Shortening the tube limits your ability to raise your handlebars in the future. This could be needed to compensate for flexibility changes or bike fit adjustments.

Fork Replacement Required: In severe cases where the tube is cut way too short, your only option may be getting a new fork entirely. This can be expensive and time consuming.

Improper Bike Fit & Comfort: With limited stem and spacer attachment, you may not find an ideal handlebar position. This can lead to discomfort on long rides.

While too short is bad, also avoid leaving more than 40mm of steerer tube above your stem. 

This risks applying torque force and potentially damaging your fork.

Also Read: Crown Race Won’t Fit on Fork

Prevent Cutting Your Steerer Tube Too Short

Avoid this whole problem by measuring twice and cutting once:

Prevent Cutting Your Steerer Tube Too Short
  • Use the minimum insertion line on your stem to mark the lowest point of safe cutting. Never cut below this line.
  • An extra 10-20mm gives you room for adjustments so you don’t end up too short.
  • Preview the assembly with spacers before cutting to visualize proper length.
  • Take off a small amount of length and test the fit. Then cut more if needed vs. cutting everything at once.
  • If at all unsure about sizing, let a professional do the cutting. Their expertise can prevent mistakes.

Frequently Asked Questions

Still have some questions about cutting your steerer tube? Here are answers to some frequently asked questions:

Is a Steerer Tube Extender Safe to Use?

A steerer tube extender can add back a small amount of length if cut a few mm too short. 

This can provide enough room for proper stem insertion and spacer stacking. 

As long as minimum insertion guidelines are followed and the extender stays below 40mm of total length, it can be a safe temporary fix. 

But consult a mechanic before using one.

How Long Should I Cut My Steerer Tube?

For most modern threadless stems, leave at least 30mm of steerer tube extending above the stem’s top. Even better is allowing 40-60mm of total length to the top of the steerer tube after cutting. 

This extra room gives you stacking room for spacers both above and below the stem.

How Do I Know if My Steerer Tube is Too Short?

Signs that your steerer tube may be cut too short include not being able to achieve proper stem insertion depth, insufficient spacer stacking height, or a front-end that feels unstable or wanders. 

If your stem’s minimum insertion line is visible above the steerer tube, it is likely cut too short for safe use.

Bottom Line

Never compromise your safety just to avoid fork replacement. 

If the stem doesn’t have enough insertion or the bike doesn’t feel stable, a new fork is required.

Certified bike mechanic based in Orlando, Florida. With over 15 years of knowledge and experience in the industry, I can help you diagnose issues and fix them.

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