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550Performance LLC

European Mail In ECU Reflash | MY21-22 Honda CRF 300L and Rally | 95 Octane Stage 1.5

European Mail In ECU Reflash | MY21-22 Honda CRF 300L and Rally | 95 Octane Stage 1.5

Regular price $199.99 USD
Regular price Sale price $199.99 USD
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Mail in factory ECU reflash for the European (38770-K1T-E11) 2021-2022 Honda CRF 300L. This tune is built around 95 octane (RON) fuel which helps increase power throughout the entire engine speed range. The most notable bumps come in the low to mid-range engine speeds. Primary fuel tables have been updated to support maximum power with added airflow from aftermarket exhaust system, air box modifications, and CB300R camshafts. Additionally, the secondary fuel tables have been revised as well to match the changes to the calibration in the event of a sensor failure to better protect the engine. General improvements to the cold start and target idle speed strategy have been made to promote fast warmup and robust engine starts. Revisions to this calibration specifically work to reduce, or in some cased completely remove, the 5000 RPM engine rattle. This tune is compatible with the following modifications: high flow airbox lid, high flow velocity stack, and aftermarket air filter. A properly equipped bike with this the stage 1.5 tune, Yoshimura RS4 full exhaust system, aftermarket air filter, high flow airbox lid, and high flow velocity stack can expect to pick up about +23% in power and +12% in torque.


  • Engine speed limiter set to 11000 RPM
  • Updated warm idle speed set to 1500 RPM
  • Revised ignition timing tables for 95 octane (RON) fuel
  • Primary fuel tables mapped for best power
  • Secondary fuel tables mapped for component protection
  • Redefined startup and post-start fuel mapping
  • Revised target idle speeds during warmup
  • Adjusted tip-in accelerator pump fueling
  • Minimizes 5000RPM rattle
  • Removes check engine lights associated with the EVAP and PAIR systems
  • Deceleration fuel cut altered to alleviate on/off throttle sensitivity

Hardware Requirements:


This is a mail-in tuning service. Return shipping cost is included when checking out. Buyer is responsible for any costs incurred while arranging shipment to our shop. Default product selection includes shipping insurance for the amount to cover a new service ECU.

Directions and Shipping Information:

Select the tune that best fits your vehicle and add it to your cart to complete the purchase. A confirmation email with an order number along with instructions on how to send the ECU to our shop for service will be sent to the email address provided. 

Typical turn time is 1-3 business days from when we receive the ECU. In some rare cases this can extend to a week.  All shipments from 550Performance LLC will be insured to cover the cost of the ECU if selected. Estimations of transit time and general notes regarding shipping providers are outlined below.

  • DHL shipping to the EU will take 3-6 business days on average
  • USPS First Class Mail shipping to the EU will take 7-21 business days on average
  • USPS Priority Mail shipping to the EU will take 6-10 business days on average
  • USPS Priority Mail Express shipping to the EU will take 3-5 business days on average

DHL assesses a customs brokerage fee in addition to tariffs and VAT. This fee can be significant, in some cases comprising nearly half of the total import costs. USPS does not charge this fee for its services.

For those shipping an ECU from outside of the United States, an export harmonization code of 871410 must be provided.

The declared value of your package should be minimized as the ECU is already owned by you. This value does not represent the actual insured value.


Please be aware that 550Performance LLC is not responsible for and will not refund any charges incurred upon arrival of our products abroad. This includes charges such as, but not limited to: Custom fees, import taxes, delivery delays, fees, or duties. All of these fees must be paid by the customer upon delivery of the product.

Prices indicated on our website and shipping cost do not include additional and applicable charges. Placing an order with 550Performance LLC implies you are accepting responsibility for any charges associated with importing our products into your country.



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