What Size Dirt Jumper Should I Get For My Height?

Dirt jumpers belong to a small biking niche, thus less popular. Sadly, their unpopularity means very few buyers know how to size them. So, are you among those asking, ‘what size dirt jumper should I get?’

Generally, the average height cyclist, 5’7”-6’1” tall, requires a medium-sized dirt jumper with an average Reach of 400-410mm and an effective top tube of about 558 584mm.

So, if you are taller than average, you’ll need a large frame with a longer reach and top tube length. Likewise, if you are shorter, you’ll need a more petite frame with a smaller Reach and a smaller top tube.

I’ll explain all these elements in detail to help you find a dirt jumper that matches your height.

what size dirt jump do i need

Summary: 5 Best Dirt Jumpers Available on Amazon

  1. Mongoose Fireball Dirt Jump Mountain Bike
  2. Diamondback Bicycles 2014 2nd Assault
  3. Diamondback 2013 Option Hardtail Dirt Jumper
  4. Mafiabikes Blackjack D 26” BMX Jump Bike
  5. Redline D26 Single Speed Dirt Jump Bike

What Size Dirt Jumper Should I Get? Reach vs. Top Tube Length

Generally, you can determine your ideal dirt jumper size by considering the bike’s reach or its tube length.

Reach Vs. Dirt Jumper Size – How To Size A Dirt Jumper

The reach refers to the horizontal distance from the head tube middle part to the central part of the bottom bracket.

Note that dirt jumper bike brands like Transition, Canyon, and Norco list the reach measurements, making the sizing easier.

Others, however, don’t do that, and so you have to physically measure the distance, which is hard if you are shopping online.

Luckily, you can always ask the manufacturer or seller if the reach length is not listed.

Now, what do you do with the reach?

Well, it helps you find the perfect bike frame size to match your height.

Here’s a table that shows you what I mean.

Dirt Jump Brand Reach (mm)Frame Size Rider’s Height
Canyon400mmSmall4’7”-5’7” (140-170ccm)
417mmLarge5’3”-6’6.7” (160-200cm)
Norco380mmSmall4’7”-5’7” (140-170cm)
405mmMedium5’7”-6’1” (170-185cm)
430mmLarge6’1” + (185cm +)
Transition415mmSmall4’7”-5’7” (140-170cm)
440mmLarge5’7”-6’1” (170-185cm)
465mmx-Large6’1” + (185cm +)

From the table, it’s clear that different jump bike brands have different sizes. For example, a small Canyon frame is almost the same size as a medium Norco frame, and a small Transition frame is nearly the same size as a large Canyon frame.

So, you have to carefully look at the technical information that the dirt jumper manufacturer provides to help you pick the correct size.

Once you get the Bike Reach correct and match it with the right frame size and height, you can find the ideal bike size.

If this method looks hard, then try finding the bike’s top tube length, as I explain below.

Dirt Jumper Size

Top Tube Length vs. Dirt Jumper Size – What Size Dirt Jump Do I Need?

Some dirt jumper manufacturers list the top tube lengths of their bikes. So, you can also consider it to determine the bike frame size.

Mark you; we are not talking about the actual top tube length but the effective top tube length (also known as the horizontal tube length).

Usually, this is the distance between the seat tube and the head tube, and it’s usually more extended than the bike’s actual top tube length.

Nonetheless, the horizontal top tube length, just like the reach, differs from brand to brand.

Below is a table that you can use to match the bike’s top tube length with the frame size and rider’s height.

Effective Tube Length Frame SizeRider’s Height
21.5-22” (546-558cm)Small4’7”-5’7” (140-170ccm)
22-23” (558-584cm)Medium5’7”-6’1” (170-185cm)
23”+ (584cm +)Large6’1” + (185cm +)

Reach vs. Top Tube Length – What Should I Go For?

Now that I’ve covered the reach and top tube and how they influence the bike frame size, what should you go for?

Note that even though the top tube length gives you an indication of the frame size, it’s not as reliable as the reach length.

That’s because the seat tube angle differs from brand to brand, affecting the top tube length. That’s unlike the reach, which is not influenced by the seat tube angle.

Essential Tips On Sizing A Dirt Jumper

It’s worth remembering these tips when sizing a dirt jumper:

  • Most Dirt Jumpers Come in Just One Size

Note that not all dirt jumper bikes come in multiple sizes.

As a matter of fact, most bike brands only have one size for each model. A perfect example is Mongoose.

Their top dirt jumper bike line, the Mongoose Fireball, comes only in one size to suit riders who are 5’4”-6’2” (163-188cm) tall.

That includes the Mongoose Fireball Moto, Mongoose Fireball SS, and the original Mongoose Fireball.

What Size Dirt Jumper Do I Need
  • The Handlebar and Stem Are Adjustable

Just because the frame size matches your height doesn’t always mean that the bike will fit you outright. Similarly, just because the frame is small doesn’t mean that the dirt jumper won’t fit you.

You can continually adjust the bike’s handlebar and stem to find your fit. Remember, a longer stem lengthens the reach while a shorter one accomplishes the opposite.

After all, some bikes feature shorter frames to improve their handling, but the stems are adjustable, depending on preference. With most stems averaging 30-50mm, you can constantly adjust it to match your taste.

Overall, you could use a raise on the handlebar if you are tall.


1. What Size Dirt Jumper Do I Need?

The easiest way to determine if a dirt jumper bike fits you is to look at its reach and top tube length. Once you have the two measurements, you can use them to determine a frame size that matches your height.

So that you can understand what I’m driving at, here’s a table to guide you.

Frame SizeReach (mm)Horizontal Tube Length (mm)Rider’s Height
Large410mm +584mm +6’1” +

2. Why Are Dirt Jumpers So Expensive?

Dirt jumpers are generally expensive because they are specialized bikes with high-end components. Though they don’t attract a big market, given their small niche, the few they attract are obsessed by them and don’t mind paying more.

3. How Big Should A Dirt Jumper Be?

In most cases, a size 15-inch or 16-inch is okay for most people. Note, however, that everyone has their preference.

Some cyclists prefer smaller dirt jumpers for easy control, and others want a size that fits them.

Overall, ensure the top tube length and reach of the dirt jumper matches you.

4. How Do I Choose A Dirt Jump Bike?

While there are so many buying considerations like frame quality, wheel strength, and fork, nothing is more important than the correct size.

You have to pick a dirt jumper bike that matches your height.

That means you’ve to consider its effective top tube and Reach carefully. Once you do, you can look at the other buying considerations.

5. What Is The Best Dirt Jumper?

The best dirt jumper should be easy to ride and maintain. It should also be high quality in build, featuring lasting components.

That undoubtedly describes the following dirt jumper bikes available on Amazon:

  1. Mongoose Fireball Dirt Jump Mountain Bike
  2. Diamondback Bicycles 2014 2nd Assault
  3. Diamondback 2013 Option Hardtail Dirt Jumper
  4. Mafiabikes Blackjack D 26” BMX Jump Bike
  5. Redline D26 Single Speed Dirt Jump Bike

6. Are Dirt Jumpers Worth It

Dirt jumpers unify the worlds of a mountain bike and the freestyle BMX. If you want a bike that can give you a taste of both sides, then you should invest in a dirt jumper.

Dirt jumpers are unequaled when it comes to performing aerial stunts and high jumps on two-wheels.

So, yes, these bikes are worth paying for if you are into stunts, street tricks, and all kinds of adrenaline-rushing exploits.

7. Should I Get A Dirt Jumper Or BMX?

BMX bikes are best for dirt racing and obstacles jumping, while dirt jumpers are best for aerial tricks and high jumps on dirt paths.

8. Is A Dirt Jumper A BMX?

We’ve some dirt jumpers that are BMX like the Mafiabikes Blackjack D 26 Wheelie Bike but not all dirt jumpers are BMX. Some are just modified Hardtail mountain bikes or single-speed bikes.

Closing Thought: What Size Dirt Jumper Should I Get?

So, what size dirt jumper should I get? As shared, you have to consider the bike’s reach or effective top tube or both to determine your ideal bike size.

You can take advantage of the sizing guide that I’ve shared above to find it.