The Tool Desk
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Which CRF450 model years does the T500 kit fit?
Dirt Rider’s December 18, 2025 first look describes two T500 versions:
| Reported kit version | Compatible models reported | Model years |
|---|---|---|
| Earlier version | Honda CRF450R and CRF450RX | 2021–2024 |
| Later version | Honda CRF450R and CRF450RX | 2025–2026 |
This reporting does not establish fitment for every CRF450 generation or for other models such as the CRF450X. Before ordering, ask Tomasin Racing or the seller to confirm that the kit generation matches the exact model, year and configuration of your motorcycle. Do not assume a kit for one year group will fit another.
What does the T500 conversion include?
The T500 replaces the CRF450’s four-stroke engine with a 500cc two-stroke package. Dirt Rider’s 2025 report lists engine, intake, exhaust, ECU, cooling and electrical components. Garage Eleven describes a fuel-injected setup with a dedicated ECU, reed-valve induction, modular billet head, racing crank and rod, titanium studs and an electric water pump. These are product and installer descriptions; the cited coverage does not provide independent power measurements.
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- High quality 53Cr21Mn9Ni4N (21-4N) steel material, durable and efficient, good working condition
- Advanced technology to improve intake and exhaust efficiency
- Fitment: CRF450R 2002 2003 2004 2005 2006
- OEM replacement complete intake exhaust valve set
- Quality Assurance! If you are not satisfied with our products, we accept all of the return, replacement or refund requests
Why the CRF450 donor still matters
This is a conversion built around an eligible CRF450, not simply a universal engine dropped into any CRF chassis. The 2026 Dirt Rider report identifies OEM parts reused in the conversion, including the starter motor and gears, stator and flywheel, primary gears, clutch assembly, crankcase covers and shifter. Garage Eleven also describes gearbox reuse options.
Before agreeing to a build, get the seller or installer to specify which parts the kit supplies, which parts carry over from the donor, whether a gearbox is included, and what donor condition is acceptable. Garage Eleven says its workshop assesses the donor, installs the engine, commissions the wiring, fuel injection and cooling, sets up the ECU, and runs the motorcycle before handover.
Rank #2
- The combination of fine craftsmanship and innovative design not only enhances the visual appeal of the motorcycle but also reflects the rider's discerning taste.
- Our goal is to bring you the best shopping experience through our motorcycle products and ensure that you can use them with confidence.
- Exhaust will add more performance, speed and power to your motorcycle. While providing a stylish look and a deeper exhaust note.
- for CRF450R CRF450RX 2015 2016 Slip-on Motorcycle Exhaust Muffler Middle Link Pipe
- The deep exhaust pipe sound brings you a thrilling experience, the ultimate driving experience.
How much does a T500 kit or conversion cost?
The figures below come from different markets and describe different scopes of work, so they are not directly comparable. Confirm current availability, included parts and final pricing with the seller.
| Route | Reported price | Source and qualification |
|---|---|---|
| Kit without gearbox | €8,500 | Dirt Rider, December 18, 2025 |
| Kit with gearbox | €10,500 | Dirt Rider, December 18, 2025 |
| Ready-to-ride 2026 CRF450R/T500 | €17,000 | Dirt Rider, December 18, 2025 |
| Australian kit supply | A$19,990 | Garage Eleven listing accessed October 8, 2026; indicative pricing |
| Australian conversion using the customer’s donor bike | A$22,500 | Garage Eleven listing accessed October 8, 2026; indicative pricing |
| Australian complete build | From A$34,900 | Garage Eleven listing accessed October 8, 2026; indicative pricing |
| Australian build with a new donor | From A$41,900 | Garage Eleven listing accessed October 8, 2026; indicative pricing |
Garage Eleven says its Australian prices may change with exchange rates, freight and import costs, donor condition, parts availability and final scope. Ask for a current written quote that spells out the gearbox, donor, installation, ECU setup, shipping and any import costs. The available price reports do not establish lead times.
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Rank #3
- High quality, durable and efficient, good working condition
- Fitment: for CRF450R 2002 2003 2004 2005 2006 2007 2008 TRX450R 2006 2007 2008 2009 Replace 12205-MEB-P00 & 12204-MEB-P00
- for TRX450ER 2006 2007 2008 2009 2010 2011 2012 2013 2014
- for CRF450X 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
- Quality Assurance! If you are not satisfied with our products, we accept all of the return, replacement or refund requests
Does the T500 conversion need a CRF450 donor bike?
For the reported conversion routes, yes: the kit is specified for CRF450R/RX model-year groups and uses selected OEM components from the donor. Buyers can encounter different arrangements—buying a kit, paying an installer to convert a customer-owned bike, or purchasing a complete build—but each seller should clarify exactly what is included. A kit-only price is not the same scope as an installed conversion or a ready-to-ride motorcycle.
Can you register a T500 CRF450 for the road?
Garage Eleven states that its T500 is designed for closed-course competition, is not ADR compliant and cannot be road registered in Australia. That statement applies to Australia; it does not establish the registration status in other countries. Elsewhere, check local rules for vehicle registration, emissions, insurance and competition-class eligibility before buying or modifying a bike.
Rank #4
- Compatible With Honda Models: CRF450R 2002-2006
- OEM Numbers: Exhaust Valve: 14721-MEB-670; Valve Spring: 14752-MEB-670; Stem Seal: 12209-GB4-682; Valve Cotter: 14781-MAT-000
- Order Includes: 2x Exhaust Valve, 2x Spring, 2x Stem Seal, 4x Cotter
- Dimensions: Exhaust Valve: Length: 84.5 mm - 3.32 in, Width: 31 mm - 1.22 in; Valve Spring: Length: 43 mm - 1.69 in, Width: 24 mm - 0.94 in; Stem Seal: Length: 10.5 mm - 0.14 in, Width: 8 mm - 0.31 in, Inner Diameter: 4.5 mm - 0.2 in, Outer Diameter: 7.6 mm - 0.3 in; Valve Cotter: Length: 7 mm - 0.27 in, Width: 3 mm - 0.11 in, Height: 5.6 mm - 0.22 in
- Fitment Verification: Please review the description and images to ensure correct fit.
Is “widowmaker” a proven description of its performance?
“Widowmaker” is colorful headline language, not a documented safety rating or independent performance finding. The cited material does not establish a measured horsepower figure, a comparative test, a reliability rate or an independent safety assessment. Judge the conversion on confirmed fitment, build scope, intended use and the evidence available for the particular bike—not on that label.
Quick Recap
Best Value
- Order Includes: 1x Intake Valve, 1x Exhaust Valve
- Compatible With Honda: CRF450R CRF 450R 2007 2008
- Part Numbers: Intake Valve: 14711-MEB-670 / Exhaust Valve: 14721-MEN-A00
- Dimensions: Intake Valve: Length: 84.6 mm - 3.3 in, Width: 35.9 mm - 1.4 in, Height: 35.9 mm - 1.4 in / Exhaust Valve: Length: 84.1 mm - 3.3 in, Width: 29.7 mm - 1.2 in, Height: 29.7 mm - 1.2 in
- We strongly suggest comparing the posted picture to the unit(s) that needs to be replaced.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
