DH Motoring

Sale price $105.00 Regular price $149.00

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Customer Reviews

Based on 183 reviews
Chris Jordan

David is the man

Simon Valadez
ECU not working

I installed the ECU on my 2020 Honda Grom and it ran perfect for one day but the next day through a check engine light code about my temperature oil sensor and now my bike will not start or run. In contact with your support I have not came up with any resolutions and why it’s messing up my bike. Now I can’t enjoy riding my bike and if you can’t resolve it then I will have to return it and need my OEM ECU to re install and look into another product.

Andrew K
Best of the bunch

There are many guys out there flashing mini bikes these days, DHM David is top-notch and actually gives his customers the service and answers are looking for. He also is extremely helpful and understanding when it comes to building your dream machine.

Brandon Lewallen
Stage 1 Grom flash

Woke my Grom up!

Raymond Acevedo

1000% satisfied with the ECU. You can notice the difference right away. Love it !!! The best mod I have done on my grom.

**Mail-in ECU turnaround time is only 1-2 business days!

DHM is here to offer you the original flash tuning solution for the Honda Grom / Monkey! Our stage 1 software cleans up the air/fuel ratio and optimizes ignition timing on bikes with intake and exhaust modifications.

Looking at the dyno graph, you'll see the blue and green lines that are the graphs for the stock, unmodified ECU. It runs extremely lean up top and therefore only makes around 6-7HP at 9200rpm. By controlling the air/fuel ratio we're able to extract up to 3HP more in the higher RPMs. The peak number is only about 1hp but in a race on the street the tuned bike will continue to pull gear after gear because it does not lose power after 7,000rpm.

Our ECU flash not only increases horsepower, but it also makes the engine run safer now that it has adequate fueling.

***This is the best alternative to a fuel controller, especially at the price point. You no longer need to spend hundreds of dollars on a tuner if you only have simple bolt-ons on your bike. If your bike is running a modified intake and exhaust this is your ticket to a smooth running bike with OEM like ride-ability. Since we retain the stock ECU, the bike will start, run and idle like normal, but will produce more and safer power throughout the rev range.


  • Up to a 3HP gain at high rpm compared to an untuned ECU!
  • Raised rev limit of 9750rpm (compared to 9250rpm stock) higher limits available upon request
  • Corrected air/fuel ratio
  • Additonal ignition timing advance for improved throttle response and power
  • Higher top speed
  • Better mid range and torque
  • Optional tip-sensor delete
  • Optional cold-start high idle delete
  • Optional closed loop delete (will allow your piggyback to make changes to the closed loop portion of the map)

***Once you've completed checkout, you will receive the shipping info as well as a link to a form so you can list your exact modifications. Each tune is tailored to your exact modifications!

How to order: 

You can mail us your ECU and we will flash it and get it back in the mail by the following business day (1-2 day turnaround time). (After checkout you'll receive an email confirmation with shipping instructions.

If you do not wish to have the downtime, we can provide a core flashed ECU to you. You will have to pay a core charge ($95 for SF and Monkey, $110 for OG) which will include a preflashed ecu. You can choose to return your stock ecu for a $75 core refund after you've received the new one.  

If we revise the stage 1 software in the future we will update your ECU for free (you just pay shipping both ways). If you'd like to update to a different setup later on (big bore, cam, etc) we only charge a $35 upgrade fee which includes return shipping to you as well.