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    On all orders over $100

  • Trusted by 30,000+ Riders

    Shop with the Originals Since 2019

  • Local Expert Support

    Get real help when you need it

  • Over 70 Locations

    Nationwide Sales & Service

  • 2 Year Warranty

    On all Adults E-Bikes

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SIRRIS SUSPENSION

Sirris F43 MX Tune Ultra Bee Fork

$4,841.00 NZD

Note: Some suspension is custom tuned and made to order. Delivery can be Approximately 2weeks.

Free Shipping

At Ampd Brothers, we offer FREE shipping on all orders over $100 and a flat $8 rate for orders under $100 within Australia.

Oversized items over 50kg, such as Sur-Ron Motorbikes will incur a $199 freight fee to WA, TAS, and NT. Additional fees apply to remote locations where services may be limited (e.g., Broome, Lord Howe, Kangaroo Island) we may adjust shipping fees or cancel orders to these areas.

Delivery times range from 2 to 14 business days, excluding public holidays and peak periods.

Ensure your shipping address is attended to avoid missed delivery fees. We securely box all orders but items like bikes require some assembly—refer to our assembly page or contact your local dealer for assistance (assembly fees may apply). Note, we do not ship large items to P.O. Boxes or Parcel Lockers, though small articles can be delivered to P.O. Boxes via AusPost.

For international shipping, refer to Shipping prices at checkout or contact us for a detailed quote. All rates are charged in AUD$ and exclude import taxes or charges. For full details, please refer to our Shipping Page or contact us.

Fast Easy Returns

Fast, easy returns for eligible new and un-used items purchased within 30 days. Our friendly team can also assist you with the return of your item. Check out our Returns Page for full T&C's as well as eligible items.

Comprehensive Warranty

Here at Ampd Brothers we stand behind all our products nation wide regardless of where you live so you can rest assure knowing your purchase comes backed by a renowned Aussie Family Owned Brand.

Warranty Periods:

  • 2 Year's on Ampd Bro's Adult Electric Bike Models 
  • 1 Year on Kids Electric Bikes (EVO Racing & Lil Rippa)
  • 1 Year on RFN Motorcycles
  • 1 Year on Surron Light Bee, Hyper Bee & Ultra Bee
  • 6 Months on Surron Storm Bee
  • 6 Months on Vortex Skateboards
  • 6 Month's on Products Sold as "Ex-Demo" or "Ex-Display" items
  • 3 Months on Refurbished or Repaired Products
  • 3 Month's on any Parts, Accessories & Bike Trailers*

Our Extensive Warranty applies Australia Wide for all our products. *T&C's Apply for full information on our Warranty Click Here.

 

Why Ampd Bros

Why Choose Ampd Bros® Electric Bikes?

The Original Aussie Family Owned Brand

Ampd Bros is a proudly 100% Australian family-owned brand, established in 2019. We pride ourselves on our local roots and dedication to our community. When you shop with us, you're supporting a business that values quality craftsmanship and customer service.

Expert Support and Unmatched Service

Our team of industry-skilled experts is available five days a week to provide you with personalized, knowledgeable assistance. With nationwide sales and service coverage in over 70 locations, you can rely on Ampd Bros for exceptional support wherever you are. We also offer a comprehensive 2 year nationwide warranty on our range of Ampd Bros Bikes, ensuring peace of mind with every purchase.

Innovation and Performance

As Australia's First and Original Aussie fat bike brand, we are pioneers in pushing the boundaries of design and performance. Our products are crafted in conjunction with the industry's top experts, ensuring every ride is both reliable and exhilarating. With Premium 21700 Samsung battery cells that are 30% larger than those of other brands, our bikes deliver unmatched power and longevity.

Convenience and Reliability

We understand the importance of staying on the road, which is why we maintain a full inventory of parts at all times. Our Fast and FREE Delivery service ensures you receive your bike quickly and our commitment to premium quality means your bike is tried, tested and proven over the years. Plus, with interest free financing options up to 36 months, you can ride now and pay later.

Inspiring Bold Adventures

At Ampd Bros, our core value is to inspire people to "Ride Bold and Beyond Ordinary." With a track record of over 25,000+ satisfied customers, our fat bikes and beach cruisers are designed to elevate your riding experience and take you on unforgettable journeys.

Join the Ampd Bros family and experience the difference of riding with a brand that prioritizes quality, innovation and customer satisfaction.

Ride bold. Ride Ampd Bros.

Description

MX Tune is a motocross specific tune with balance, control, and bottoming resistance for the fastest speeds. It's firm suspension for maximum control and support for huge jumps, whoops and fast cornering. If you select the EBMX or MX spec, you’ll compromise a bit of trail plushness for improved bottoming resistance.

RIDER WEIGHT SPECS:

Sirris offers five weight ranges to choose from when selecting your MX Tune F43 fork. (Listed weight ranges are rider weight without riding gear on. 15 pounds of riding gear is calculated into the weight ranges)

LIGHT 54 - 73kg / 120 lbs - 160 lbs (Light = 4.4/4.4 springs)
MEDIUM 73 - 91kg / 160 lbs - 200 lbs (Medium = 5.0/4.8 springs)
HEAVY 91kg - 109kg / 200 lbs - 240 lbs (Heavy = 5.4/5.0 springs)
X HEAVY 109 - 127kg / 240 lbs - 280 lbs (X Heavy = 5.4/5.4 springs)
XX HEAVY 127 - 145kg / 280 lbs - 320 lbs (XX Heavy = 5.4/5.4 springs)

Fork spring rates listed above are left side/right side.

FORK SPECS:

Architecture
Upside down fork

Travel
246 mm

Free length
856 mm

Fork weight, includes clamps and steerer
22 lbs / 10kg

Stanchions
Ø43, high tensile steel with hard chrome

Outer tubes
Seamless 7050 aluminum, type 3 hard anodized coating

Drop outs
Forged 6061 aluminum, type 3 hard anodized coating

Triple clamps
Forged 6061 aluminum, type 3 hard anodized coating

Steer tube 
Seamless 7050 aluminum, type 2 anodized coating

Damping
Symmetrical, adjustable closed cartridge with spring backed IFP

Damper bodies
Seamless 7050 aluminum, type 3 hard anodized coating

Rebound
Dual side high tensile steel spring, adjustable

Adjusters
External compression and rebound adjustment

Seals
NBR 

Guards
High impact PP, 210-degree wraparound

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Ride Bold, Ride the Best.

The Original Aussie Bike Brand Since 2019. #AMPDBROS

Introducing Sirris Suspension

A NEW ERA IN E-MOTO SUSPENSION PERFORMANCE IS HERE

F43 Forks

  • TRUE SYMMETRICAL Closed Cartridge

    BALANCED PERFORMANCE
    Balanced load, race-ready, high performance. No matter how hard you ride or how many laps you take, our closed cartridge forks will never fade and will always feel predictable.

    HYDRAULIC BUMP STOP 
    Go big with confidence, control, and comfort. Our hydraulic bump stop design and construction gives you a soft landing at max stroke even on the most aggressive impacts.

    HIGH TENSILE LIGHTWEIGHT SPRINGS 
    Weighs only 8.8 lbs (4 kg) per leg (standard configuration spring).

  • Built to Last NO COMPROMISES

    DUAL OIL CIRCUITS FOR OPTIMUM PERFORMANCE
    Separating lubrication and damping oils allows us to further optimize high and low speed damping performance.

    HIGH QUALITY MATERIALS + SURFACE TREATMENTS
    All cartridge bodies and outer tubes are hard anodized 7XXX series aluminum providing high durability and scratch resistance to keep your ride in top condition.

  • EVERY RIDER & RIDING STYLE

    Fully tunable valving on compression and rebound, with spring rates matched to rider weight and riding type. Adapt your suspension setup for different types of rides, enhancing overall riding experience.

    Compression, rebound, and preload adjust plus custom spring rates for all riding styles and rider sizes.

R46 Shocks

  • EXCEPTIONAL RESPONSIVENESS

    Fully tunable valving on compression and rebound, with spring rates matched to rider weight and riding type. Adapt your suspension setup for different types of rides, enhancing overall riding experience.

  • TUNING WITHOUT COMPROMISE

    LSC (Low Speed Compression)
    Superior pressure balance and frequency response providing the ultimate overall responsiveness and performance for riders.

    Optional 2SC will be available soon. The 2SC will offer a wider adjustment range than the LSC. LSC and 2SC fit in the same cavity and are cross compatible (with a rebuild). Both will be offered as service parts.

  • BUILT TO LAST

    High Durability Finishing
    Type 3 hard anodized body cap, body, reservoir, end cap, spring hardware, and clevis. Induction heat treated, hard chrome hollow shaft. The rear shock will look like new, even after thousands of miles.

    Extremely Easy to Rebuild
    Fully serviceable design ensures easy rebuilds and custom tuning.

Sirris FAQ's

Product Help

Sirris Suspension Owners Manual

OWNER'S GUIDE

Follow the guidelines and instructions provided in this owner’s guide so that you are able to properly set up, use, and maintain your new Sirris suspension products.

Download Now

Installation Videos

Break-In Period Note

The Sirris F43 fork is a symmetrical closed cartridge design with two independent sealed dampers. It will break-in over the first 5 hours of use with significant improvements in friction.We recommend that you don’t make significant changes to clicker positions or valving until after the 5 hour break-in period.

Sirris 2 Year Warranty

LIMITED WARRANTY INFO

Your Sirris fork and shock are warrantied against manufacturing defects for a period of 2 years. Normal wear and regular maintenance are not covered.

Sirris makes the following LIMITED WARRANTY with respect to its suspension products:  

LIMITED TWO (2) YEAR WARRANTY ON SUSPENSION PRODUCTS 

Subject to the limitations, terms and conditions hereof, Sirris warrants, to the original retail owner (consumer) of each new Sirris suspension product, that the Sirris suspension product, when new, is free from defects in materials and workmanship. This limited warranty expires two (2) years from the date of the original Sirris suspension product retail purchase from an authorized Sirris dealer or from a Sirris authorized Original Equipment Manufacturer where Sirris suspension is included as original equipment on a purchased vehicle. 

TERMS OF WARRANTY 

This limited warranty is conditioned on the Sirris suspension product being operated under normal conditions and properly maintained as specified by Sirris. This limited warranty is only applicable to Sirris suspension purchased new from an authorized Sirris source and is made only to the original retail owner (consumer) of the new Sirris suspension product and is not transferable to subsequent owners. 

Should it be determined, by Sirris in its sole and final discretion, that a Sirris suspension product is covered by this limited warranty, it will be repaired or replaced, by a comparable model, at Sirris’s sole option, which will be conclusive and binding. THIS IS THE EXCLUSIVE REMEDY UNDER THIS LIMITED WARRANTY. ANY AND ALL OTHER REMEDIES AND DAMAGES THAT MAY OTHERWISE BE APPLICABLE UNDER THIS LIMITED WARRANTY ARE EXCLUDED, INCLUDING, BUT NOT LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OR PUNITIVE DAMAGES. 

This limited warranty does not apply to normal wear and tear, malfunctions or failures that result from abuse, neglect, improper assembly, alteration or modification, improper or unauthorized repair or maintenance, crash, accident or collision, or other abnormal, excessive or improper use. 

THIS IS THE ONLY WARRANTY MADE BY SIRRIS ON ITS SUSPENSION PRODUCTS AND COMPONENTS, AND THERE ARE NO WARRANTIES WHICH EXTEND BEYOND THE DESCRIPTION HEREIN. ANY WARRANTIES THAT MAY OTHERWISE BE IMPLIED BY LAW INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE EXCLUDED. 

For questions regarding this warranty or Sirris products please email info@ridesirris.com, or visiting www.ridesirris.com. 

When making a claim under this Limited Warranty you will be required to provide to an authorized Sirris Service Center: 

1. The Product (or the affected part) and 

2. A copy of the original proof of purchase, which clearly indicates the name and address of the seller, the date and place of purchase, the product part number and if utilized, a serial number. If Sirris products are sold as part of a complete motorcycle, the motorcycle brand, model, model year, and serial number should be included. 

Service Intervals

BREAK-IN PERIOD NOTE: The Sirris F43 fork is a symmetrical closed cartridge design with two independent sealed dampers. It will break-in over the first 5 hours of use with significant improvements in friction. We recommend that you don’t make significant changes to clicker positions or valving until after the 5 hour break-in period. To best maintain the performance and durability of your product under normal use, Sirris recommends that you have regular fork and shock maintenance performed according to the service intervals listed below. 

It is important to remember that service intervals can vary depending on climate, trail conditions and riding frequency. Servicing your suspension requires special knowledge and tools. If you are unsure about working on your own suspension, contact your authorized Sirris Dealer for more information on general suspension maintenance.

Failure to follow these recommendations could affect your warranty.  

Long term non-use: If the motorcycle has been sitting unused for more than one year, complete inspection is necessary and maintenance is recommended. 

WARNING: Modification, improper service, or use of aftermarket replacement parts with Sirris forks and shocks may cause the product to malfunction, resulting in SERIOUS INJURY OR DEATH. DO NOT modify any part of a fork or shock, including the fork clamps, steerer, upper and lower leg tubes, or internal parts, except as instructed herein. Any unauthorized modification may void the warranty, and may cause failure or the fork or shock, resulting in SERIOUS INJURY OR DEATH. 

WARNING: Sirris products should be serviced by a qualified service technician, in accordance with Sirris specifications. If you have any doubt whether or not you can properly service your Sirris product, then DO NOT attempt it. Improperly serviced products can fail, causing the rider to lose control resulting in SERIOUS INJURY OR DEATH. 

Shipping

What countries do you ship to?

We currently ship to the Australia and New Zealand. However we can ship to any country. For accurate pricing please email us along with your address and order information to: info@ampdbros.com

How long will it take to receive my order?

All Sirris Suspension is custom tuned to your ride style and weight. While we do our best to carry as much stock as possible, some orders may be required to be 'made to order' and delivery can take a minimum of 2 weeks (for Australian orders, international orders may be longer). To confirm availability please contact our team.

THE ORIGINAL

Aussie Family Brand

Since 2019, with Over 70 Sales & Service Locations Australia Wide.

Sirris F43 MX Tune Ultra Bee Fork

$4,841.00 NZD

Rider Weight

  • Light
  • Medium
  • Heavy
  • X Heavy
  • XX Heavy

Terrain

N/A

Frame

N/A

Suitable Ages

N/A

Battery

N/A

Range

N/A

Motor Type

N/A

Motor Torque

N/A

Restricted Power

N/A

Motor (Off Road Unlocked)

N/A

Peak Output

N/A

Top Speed Off Road

N/A

Brakes

N/A

Suspension

N/A

Wheels

N/A
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