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HMF Optimizer

HMF Optimizer – $259.95

The HMF Optimizer is an EFI Controller that has been programmed with proper tuning specifications to ensure the ultimate performance from your HMF exhaust.

Note: Not tuning your machine will void the warranty of your HMF exhaust

License Plate Bracket

License Plate Bracket – $99.95

Designed for the 2014 Honda Grom, this bracket replaces the stock bracket and offers a crisp, clean look to the Grom.

-Fits standard U.S. Motorcycle Plates
-Replaces OEM Turn Signals and License Plate Light
-Some rewiring may be required
-Eliminates large stock fender/license plate bracket.
-Black powdercoated aluminum
-Amber Turn Signals I...

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Grom Grom Grom Grom Grom Grom Grom Grom Grom Grom Grom


Price: $199.95

Want to compare series? Click here for the exhaust visualizer.


* Production Time: 3-5 business days (?)
Shipping Time: view on map

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Note: HMF Exhausts are designed for closed course competition only.

For detailed information about exhaust options, click the (?) next to each of the options above. If you have further questions or concerns, contact our online custom service department or call 1.866.HMF.PIPE.
Note: Orders placed after 9AM EST are processed next business day.

The evolution of the scooter is here, with the Honda Grom. This bike has a 124.99cc air-cooled single-cylinder four-stroke engine with 9:3:1 compression ratio and a SOHC valve train. When we brought this into the HMF R&D Department, we weren't exactly sure what system would work best for it. After countless hours, we came up with 2 different systems: A low mount full system exhaust and a high mount slip on system. Each system has a unique sound, but both pickup 10-15% horse power gains across the board. Whichever system you choose, your Honda Grom is going to sound meaner and accelerate quicker off the line. A great compliment to an incredible machine.

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Series Available:

Performance Mini Series

The Performance Mini Series was designed for smaller cc engines and produces great sound and power output through it's specially designed core.

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Each HMF Exhaust:

Designed specifically for each machine.
Includes a 2 Year Limited Manufacturer's Warranty.
Is made of high quality Aluminum, Stainless Steel, or Carbon Kevlar.
Packed with high performance glass wool packing.
Includes Installation Instructions.
Quiet Core unavailable for street bike exhausts.
Manufactured in the U.S.A.