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The Best Performance in The Industry

Optibike SIMBB Fat R

The SIMBB line has been discontinued

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Top Speed
Maximum Range
*Max Range at 15MPH with a 170LB rider with moderate pedaling*
Motor Power
Motor Torque


The SIMBB Fat R is a Belt Drive Fat Tire E-Bike with a Rohloff 14 Speed Internal Hub. It is made in America, with legendary Optibike quality and performance. Various people in the industry have said the SIMBB is the future of E bikes. Many people still ask, “where is the battery”. They find it hard to believe the battery is in the bottom bracket with the motor, it looks so small.

SIMBB is a marvel of design and engineering. Good looking and Fast! Truly Made in American quality and award winning design of the Optibike in a super package. Avid Code R brakes, Rockshox Bluto 100mm travel front forks, 26 inch wheels with 26×3.8 Fat Tires, durable powder coated frames and Rohloff 14 Speed Internal Hub with Gates Carbon Belt Drive make the SIMBB Fat R a blast to ride.

Truly made in USA performance

The Optibike SIMBB is the only electric bike made in the USA. Each frame is hand built from aircraft 4130 Chromalloy. The SIMBB cases and motor parts are machined from 6061 aluminum and 4130 Chromalloy.

What is the SIMBB?

The Optibike SIMBB drive unit contains the battery, motor, and all the electronics in one small unit that’s weather sealed

45 day Guarantee

Optibike is the only motorized bicycle company to offer a 45 day satisfaction guarantee on its full line of e-bikes.

Ride your Optibike for 45 days. At the end of 45 days, if you do not love what we feel is the best electric bicycle on the market, send it back for a refund, no questions asked.



The Optibike SIMBB 29R is covered by a 5 year warranty on the Frame, a 2 year warranty on the Lithium Battery, and a 1 year warranty on the Suspension, Brakes, Electronics, Motor, and Drivetrain

Please see the Details page for Terms and Conditions


Detailed Specifications




Gearing and Drive







Custom Handmade in USA 4130 CroMoly Steel

Patented Optibike Motorized Bottom Bracket

36 Volt, 20 Amp-hour, 720 Watt-hour Lithium Ion

Rohloff 14 Speed Internal Hub with Gates Carbon Belt Drive

Marge Lite 26″ 32 H

Surly Nate 26 X 3.8 120TPI

Rockshox Bluto 100mm travel

Avid Code R


120/240 Volt Input, 6 Hour Charge Time