Altis Powersports Sigma Parts & Maintenance Guide (97V / 144V)

Complete parts and maintenance guide for the Altis Powersports Sigma and Delta — California-engineered electric dirt bikes with OEM parts stocked in the US.

6 min read

Altis Powersports is an electric dirt bike brand designed and engineered in California. The lineup spans from the Delta (72V, smaller-wheel youth-accessible build) to the Sigma (97.2V enduro flagship) to the Omega (144V, 250cc-class monster). The Sigma is the most commonly purchased model — this guide covers what you need to know for maintenance and parts.

Altis Sigma — The Flagship

The Sigma and Sigma MX are the performance core of the Altis lineup. Key specs:

  • Voltage: 97.2V — higher than the 72V platforms (Sur-Ron, Talaria) and comparable to the 79Bike Falcon GT Pro's 72V 50Ah setup in terms of total energy storage
  • Chain: #428H — heavy-duty pitch, same as Rawrr Mantis
  • Front rotor: 260mm — significantly larger than the Sur-Ron Light Bee X (203mm)
  • Wheel sizing: 19" front / 16" rear MX configuration

1. Drive Chain

The Sigma and Sigma MX use a #428H chain — do not substitute a #420 chain. The pitch and link dimensions are different.

  • OEM 428H Drive Chain: $73.99
  • OEM Front Sprocket 13T: $11.99
  • OEM Rear Sprocket 44T / 39T: $34.99

Check chain tension every 8–10 hours. Replace chain and sprockets together when worn — a worn chain kills new sprockets quickly. The 13T front sprocket is small for a bike of this power; some riders go to 14T for slightly more top speed at the cost of low-end pull.

2. Brake System

The Sigma's 260mm front rotor is a real advantage — larger swept area means better heat dissipation and more mechanical leverage at the lever. The caliper is a 4-piston design on the Sigma MX.

Flush brake fluid annually. Confirm fluid spec with Altis for your model year — Sigma models vary.

3. Altis Delta — The Smaller Platform

The Delta and Delta S are 72V bikes with 17"/14" wheel sizing — smaller than the Sigma's 19"/16". The Delta uses a #420 chain (same as Sur-Ron LBX) and has a lower parts cost per service.

  • OEM Brake Pads (Delta): $22.99
  • OEM Front Disc (Delta): $34.99
  • OEM Rear Disc (Delta): $34.99
  • OEM #420 Chain (Delta): $49.99
  • OEM Rear Sprocket 45T (Delta): $43.99

Delta tires: 17" front and 14" rear — these are not MX standard sizing, so tire selection is narrower than the Sigma. Source OEM replacements:

4. Electrical

The Sigma uses a wire harness that is available as an OEM replacement — useful if you've had a crash that damaged wiring:

Maintenance Schedule

  • Before every ride: Tire pressure, chain tension, brake lever feel
  • Every 8–10 hours: Chain lube and tension, pad thickness visual
  • Every 30–40 hours: Chain and sprocket replacement if worn, brake fluid check
  • Annually: Fork seal inspection, brake fluid flush, wheel bearing check

Browse the full Altis Powersports parts catalog on Wired Whips — OEM parts for Sigma, Sigma MX, Delta, Delta S, and Omega.

Frequently Asked Questions

Where is Altis Powersports based?

Altis Powersports is designed and engineered in California. The company builds the Sigma, Delta, and Omega electric dirt bikes targeting trail, enduro, and motocross use cases. OEM parts are stocked in the US and ship domestically.

What chain does the Altis Sigma use?

The Altis Sigma and Sigma MX use a #428H (heavy-duty 428-pitch) chain — the same spec as the Rawrr Mantis and some other high-performance e-motos. This is different from the #420 chain on the Sur-Ron Light Bee X and Talaria Sting. OEM 428H replacement chain is $73.99.

What chain does the Altis Delta use?

The Altis Delta and Delta S use a #420 chain — the same spec as the Sur-Ron Light Bee X and Talaria Sting. OEM replacement is $49.99.

What brake rotor sizes does the Altis Sigma use?

The Altis Sigma uses a 260mm front brake rotor and 220mm rear rotor — larger than most bikes in this class. The 260mm front provides excellent stopping power for a heavier enduro-spec machine.

How does the Altis Sigma compare to the Sur-Ron Ultra Bee?

The Altis Sigma runs a 97.2V platform (vs Sur-Ron Ultra Bee's higher voltage platform) and is positioned as a premium enduro bike engineered in California. The Sigma uses a 428H chain where the Ultra Bee uses a different spec. Both are full-size e-motos with 21"/18" wheel sizing. The Sigma appeals to buyers who want US engineering and brand support.