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DHM Reflash and Camshaft Package (Stage 2)

ECU Core
Camshaft Option


***Update 6-3-24, The Decha HR camshaft has been added as an option. It provides the same gains as a TB or DCR R2 but with a different lobe design that is not as noisy due to a larger base circle diameter. 

***If you already own an aftermarket camshaft you can still purchase our Reflash for those mods here:

****DOES NOT FIT THE 2022+ HONDA GROM/MONKEY, for the 2022-2024 model, click HERE

If your Grom already has an intake and exhaust, this is the next step!

We've created a camshaft package that allows you to add a Decha HR or TB Parts camshaft and our DHM Reflash to your bike. This will add as much as 2-3hp and will also increase your rev limit to 10,000 rpm, while also correcting the fuel and timing tables in your ecu. Your Grom will experience much stronger high RPM power, as well as the ability to pull to higher RPM before shifting. After tons of dyno and street testing, we feel this it the best bang for buck upgrade available! 

Corrected Air/Fuel ratio for your exact modifications
Increased ignition timing for throttle response and HP
13+ HP depending on your intake and exhaust setup
10,000rpm rev limiter
Normal cold start functions (no bad idle issues when cold)

DHM Reflash (more info here)
TB Parts Camshaft or Decha HR Camshaft

***Each tune is catered to your exact modifications (intake, exhaust and cam brands, etc.) After checkout you will receive a link to an online form that will ask for your bike's exact setup so we can tune it accordingly.

You have two purchase options for delivery. Once you've completed the purchase, we will email you with instructions on sending your ECU in to be reflashed. You can also choose to purchase a core ecu, we will send you a flashed ecu and you can return your original one and receive a $50 credit or keep it as a back up. 


Cam Installation:

Customer Reviews

Based on 263 reviews
kevin cram
2014 OG

Definitely 5star feedback on performance...made a couple of mistakes tho
1. The video says .004 and .007 valve lash...dhm says .003 on both. ( should've read directions)
2. Didn't know you couldn't run a baffle. Live in a quiet neighborhood so there's that...working on boring holes out in baffle. And yes it makes a huge difference between in or out!

It was definitely worth the upgrade 100%!!!


Fairly straight forward and easy install first time ever doing something like this and went smooth and definitely see the performance increase i’m very happy with the outcome and that 10k rpms is next level

Colby Williams
Great gains and service.

Met them at the Smokey Mountain Small Bore Rally. Great people, I bought the cam and flash there after having trouble with power getting up some of the hills and mountains around there. They installed it for me right there and had instantly noticable gains. No more issues with the hills and ran great.

Daniel Marr
Fast turnaround BUT!... Issues

I ordered the DHM reflash with a tbolt cam. Ran okay for a little bit, but didn't last long before I started realizing all these issues. After resetting the ECU, (which I had done a couple times already before) it seemed like the flash went bad or my ECU went bad. Bike has under a thousand miles on it and ran perfectly fine before. I reached out to DHM with my concerns and they stopped responding... Recently just bought a new STOCK ecu and gonna put the STOCK cam back in and see if the problems continue. Right now with the DHM re-flash my bike acts like its in a limp mode with rpms jumping up and down at all throttle positions and its not ride able. If DHM would like to write back to me, i'd love to figure it out and keep the cam in there.. but this whole thing has been sorta a pain in the a**. every stock grom i've had has been bulletproof. The cam and flash was science so everyone knows its not a good idea.

Huge power gains!

First off, the service was fantastic, with fast shipping.
I own a 2014 Grom with 13000 km that I had since new.
The power gain for the price is awesome, I also bought the stock air box, Koso tube with adapter. Both were easy to install, and the performance is huge. I can now cruise at 100km/h VS my old 90km/h, not to mention gaining speed going up some of the hills I travel. The engines low rpm torque is gone, and shows up in the higher engine revs 7000 rpm and up.
I am very happy with my purchase and the performance gains.