Can You Put a BMX Stem On an MTB?

Condensed answer: It’s possible to install a BMX stem on an MTB if the handlebars have a 22.2mm clamp-on diameter.

Requirements for Installing a BMX Stem On an MTB

A BMX stem would fit on an MTB when the following criteria are met:

1. The bar-clamp of the stem should match the diameter of the handlebars.

The average BMX stem has a 22.2 bar clamp. As a result, it’s too small for common MTB handlebars which have а 31.8mm clamp-on diameter.

BMX Stem Bar Clamp

Therefore, only MTB bars with a 22.2mm clamp area would fit on a classic BMX stem.

The common MTB handlebars sizes are different, however.

25,4mm, 31.8mm, and 35mm bars dominate the market. As a result, the available 22.2mm options are limited.

It’s also worth noting that most 22.2mm MTB bars are made of Chromoly steel which greatly increases the weight of the bar.

An average 22.2mm steel MTB bar weighs between 500 and 700 grams whereas a 31.8mm aluminum one is 300-400 grams.

22.2mm MTB bars are made out of steel because the diameter is too small to produce a strong bar out of aluminum.

Aluminum isn’t as dense as steel and requires more volume to match the strength of a steel component. Hence why aluminum frames have much larger tubes than steel ones.


Below is a list of 22.2mm bars that would work with a BMX stem:

BarMaterialCrossbarWeight
NS DistrictChromoly SteelNo550 grams
DMR WingbarChromoly SteelYes700 grams
Nemesis ProjectChromoly SteelNo655 grams
Gusset 3″ Open Prison 750 BarsChromoly SteelNo580 grams
Gusset 2″ Open Prison 750 BarsChromoly SteelNo560 grams
CTN Eastwood BarChromoly SteelNo590 grams
Atomlab GI Riser BarChromoly SteelNo590 grams
Renthal Jump Bar7010 T6 Aluminium AlloyNo380 grams
Black Market Molly Hatchet BarsChromoly SteelNo455 grams
Dartmoor Toxic v.2Chromoly SteelNo415 grams
Fireeye FIRE BARChromoly SteelYes790 grams
Surly SunriseChromoly SteelYes778 grams
Norther Cycles Custom Steel Sweepy Riser BarChromoly SteelNo485 grams
Fairdale MX 28″ HandlebarChromoly SteelYes453 grams
Dobermann BikesChromoly SteelNo645 grams
Average:575 grams20.28 oz
Table 1

2. The fork-clamp diameter should match the diameter of the fork’s steerer tube.

Most MTB bikes have suspension forks with a steerer that’s either 1 1/8″ from top to bottom or tapers from 1 1/8″ to 1 1/2″.

Fork Clamp Diameter

In both cases, a standard BMX stem would work because it has a fork clamp diameter of 1 1/8″.

What Are The Benefits Of Using a BMX Stem On an MTB

Looks

The primary motivation for installing a BMX stem on an MTB is appearance rather than function. Many people like the design of BMX stems and install them on their MTBs for style points.

What Are The Downsides Of Using a BMX Stem On an MTB

1. Limited Bar Choice

A BMX stem restricts you to bars with a 22.2mm clamp area. And while there’s a decent number of them on the market, the volume is nowhere near close to that of dedicated 25.4mm and 31.8mm MTB bars.

2. Heavy Bars

Most 22.2mm are made of Chromoly and some have a crossbar/brace for extra support.

Thе combo results in bars that are substantially heavier than MTB models made out of aluminum.


Conversely, larger clamp areas (25.4mm, 31.8mm and 35mm) allow designers to use hollower tubing and lighter materials such as aluminum while still achieving a satisfactory level of strength.

The larger the tube, the hollower it can be without losing strength because most of a pipe/tube’s strength comes from its outer layers.

For that reason, a pipe is stronger than a solid rod of equal mass when both are made of the same material.

Bicycle engineers have been relying on this phenomenon to produce components with excellent strength to weight ratio.

The most obvious example would be bike frames – they’re all composed of tubes.


The table below contains the weight of popular MTB bars with common diameters:

Model Weight
Renthal Fatbar® 35305g
LEVELNINE Team 35326g
Truvativ Hussefelt Comp347g
Race Face Atlas 35 320g
SQlab 3OX MTB 31.8325g
PRO FRS 31.8 40 mm Riser345g
Spank Spike 800 Race 330g
Chromag Fubars FU40330g
Ritchey Trail 2X 31.8 276g
Ritchey Comp Kyote355g
Average:325.9g/11.49oz
Table 2

Conclusion: The average weight of regular MTB bars is 325g. Meanwhile, the average weight of 22.2mm MTB bars is 575g (table 1).

The difference amounts to 250grams – a lot of weight in the world cycling.

Heavier Stems

Short MTB stems are notably lighter than BMX models because the MTB design requires less material.

The tables below compare the average weight of BMX and MTB stems:

BMX Stems

ModelWeight
Sunday Freeze298g
Odyssey Nord354g
BSD Dropped320g
United Purge382g
Fit High Top V2344g
BSD Levelled320g
Cinema Martinez286g
Animal Inverse Stem382g
Profile Acoustic272g
Fly Volcano 2281g
Average:323.9g/11.393oz
Table 3

MTB Stems

ModelWeight
Thomson Elite X4 Stem165g
Renthal Apex Stem146g
NEWMEN Evolution 318.4167g
LEVELNINE Team AM Stealth 35 Stem135g
Hope FR/AM 31.8 134g
Syntace MegaForce3 97g
Race Face Chester 35 Stem170g
Race Face Turbine 35150g
Chromag HIFI V2 200g
Chromag BZA 35 Stem165g
Average:152.9g/5.39oz
Table 4

Conclusion: On average, MTB stems are two times lighter (323.9g vs 152.9g).

Are BMX Stems Stronger?

It depends on the model. In general, both MTB and BMX stems are plenty strong to handle a lot of abuse as long as the production quality is good.

Summary

What You Need to Know

A BMX stem can be installed on an MTB only when the handlebars have a 22.2mm clamp area.

22.2mm MTB bars are made out of steel and are heavier than standard MTB bars.

On average, BMX stems are heavier than MTB models.

A classic MTB stem is plenty strong and allows you to choose between more handlebar models that are also a lot lighter than the 22.2mm options.

The only incentives to use a BMX stem on an MTB are looks or the absence of alternatives.

Leave a Reply