Altis Sigma MX Review: The 98V Electric Dirt Bike Explained
The Altis Sigma is one of the most interesting value plays in the lightweight electric dirt bike class. It runs a 98V Samsung 50S battery — higher voltage than a Sur-Ron Ultra Bee or a Talaria — with 22–25 kW on tap, for a genuine 70–80+ mph top speed at a price that undercuts the established names.
That combination sounds too good, so here is the honest picture: what the Sigma MX delivers, what you give up versus a Sur-Ron, and who should actually buy one. The full range is on the Altis brand page.
Altis Sigma MX specs and price
The Sigma runs a 98V/35Ah Samsung 50S pack and a 22–25 kW motor, for a top speed of 70–80+ mph depending on variant, gearing and rider weight. It is offered in a Standard 19"/19" setup and the MX with 19"/16" wheels. US pricing starts around $3,999 as an estimate, subject to import tariff conditions.
The higher system voltage is the headline: more volts means the motor can make power more efficiently at speed, which is how a lightweight bike hits 70+ mph. The Sigma is off-road and OHV use only — not street legal — and California riders follow Vehicle Code Section 436.1.
What you give up versus a Sur-Ron
The Sigma’s weak points are the ones you would expect from a newer brand: a much thinner aftermarket, fewer dealers who know the bike, and softer resale value. If something breaks, parts are harder to source than for a Sur-Ron, where almost every component has an OEM and an aftermarket option.
It is also a genuinely fast bike, which makes it an experienced-rider machine. The 70–80+ mph potential is not something a beginner should be near, and the ride modes that tame it are less refined than Sur-Ron’s.
Sigma MX vs Sur-Ron Ultra Bee HP
On paper the Sigma is faster than the 74V Ultra Bee HP and costs less. The Ultra Bee counters with the deepest aftermarket in the class, wide dealer support, stronger resale and more polished electronics.
Choose the Sigma for outright performance per dollar if you are an experienced rider comfortable with a smaller support ecosystem. Choose the Ultra Bee if you want the bike you can get parts and help for anywhere, and plan to keep or upgrade it for years.
Who should buy the Sigma MX
The Sigma MX suits experienced adult riders who want maximum speed and power for the money, ride private land or open OHV areas, and are comfortable being an early adopter on a less-established platform.
If you want your first electric dirt bike, or you value a proven aftermarket and resale, a Sur-Ron or Talaria is the safer choice. Contact us to confirm current US Sigma stock, variant availability and lead time before ordering.
Frequently Asked Questions
How fast does the Altis Sigma go?
The Altis Sigma reaches 70–80+ mph depending on variant, gearing and rider weight, driven by a 98V/35Ah Samsung 50S pack and 22–25 kW output. That makes it one of the fastest bikes in its price class and firmly an experienced-rider machine.
Is the Altis Sigma reliable?
The hardware — Samsung cells, a high-voltage system — is capable, but Altis has a much thinner aftermarket and dealer network than Sur-Ron or Talaria, so parts and support are harder to source if something goes wrong.
Altis Sigma or Sur-Ron Ultra Bee?
The Sigma is faster on paper and cheaper; the Ultra Bee has the far deeper aftermarket, wider support and stronger resale. Choose the Sigma for performance per dollar, the Ultra Bee for the ecosystem.