| Component | Specification |
|---|---|
| Model Range | Yamaha YZF-R1 – RN04 (2000-2001) |
| Engine Oil | SAE 10W-40, API SE/SF/SG+, JASO MA (2.9 L) |
| Tire Dimensions | F: 120/70 ZR 17 / R: 190/50 ZR 17 |
| Tire Pressure | F: 2.5 bar (36 psi) / R: 2.9 bar (42 psi) |
| Battery Type | GT12B-4 |
| Spark Plug | NGK CR9EK (Gap: 0.6-0.7 mm) |
While the original 1998 ‘RN01’ R1 sent shockwaves through the industry with its ‘no-compromise’ design, it was the RN04 (2000-2001) that truly perfected the formula. A little-known engineering highlight of the RN04 is that Yamaha’s engineers implemented over 150 component changes to reduce weight by an additional 2kg and improve the bike’s center of gravity. Most notably, the RN04 introduced the titanium exhaust muffler and a redesigned fuel tank with deeper knee recesses, significantly enhancing rider ergonomics and high-speed stability compared to its predecessor.
Engineering Evolution: From Raw to Refined
The RN04 represents the pinnacle of the first-generation R1 development. The 998cc 20-valve inline-four engine received subtle internal refinements to smoothen power delivery, addressing the somewhat ‘twitchy’ throttle response of the early models. The transmission was also overhauled to provide crisper gear changes, fixing the common ‘false neutral’ issues found in the 1998-1999 units.
Maintenance Guide & Service Requirements
To maintain the legendary performance of the RN04, strict adherence to fluid specifications and ignition tolerances is required. The 20-valve head design necessitates precise spark plug gapping to ensure complete combustion at high RPMs.
Lubrication System
The RN04 requires a high-quality semi-synthetic or fully synthetic SAE 10W-40 oil. For optimal clutch performance, ensure the oil is JASO MA certified. The total capacity for an oil and filter change is 2.9 liters.
Ignition and Electrical
The electrical system relies on the GT12B-4 battery. Given the high compression ratio, the starter motor requires a healthy amperage; if the battery voltage drops below 12.4V, cold starts can become sluggish. The NGK CR9EK plugs should be inspected every 6,000 km and replaced every 12,000 km, with a gap set strictly between 0.6 and 0.7 mm.
Chassis and Tires
Handling precision is the R1’s hallmark. The RN04 is sensitive to tire wear. We recommend a 120/70 ZR 17 front and a 190/50 ZR 17 rear. For street use, maintain 2.5 bar (36 psi) in the front and 2.9 bar (42 psi) in the rear to prevent scalloping and ensure predictable turn-in.
Frequently Asked Questions (FAQ)
What is the most common issue with the RN04?
The EXUP (Exhaust Ultimate Power) valve can become seized due to carbon buildup. Regular cleaning and lubrication of the valve cables are essential for maintaining mid-range torque.
Can I use 10W-50 oil?
While 10W-40 is the standard, 10W-50 is acceptable in extremely hot climates, provided it meets the JASO MA specification to protect the wet clutch system.