| Specification | Data |
|---|---|
| Production Years | 2011 – 2017 |
| Engine Oil | SAE 10W-40 (API SG-SM, JASO MA/2) – 4.3 L |
| Front Tire | 130/90B16 M/C 67H |
| Rear Tire | 170/70B16 M/C 75H |
| Spark Plug | NGK ILZKAR7B11 |
| Battery | YTX20L-BS |
Historical Engineering Insight: The Kawasaki VN 1700 Voyager Custom (VNT70J) stands as a pivotal moment in Kawasaki’s cruiser evolution. It was the first “bagger” in their lineup to implement the K-ACT (Kawasaki Advanced Coactive-braking Technology) ABS. Unlike standard linked systems, K-ACT uses a dedicated ECU to analyze brake force and vehicle speed, dynamically distributing pressure between the front and rear calipers to prevent chassis pitch—a critical engineering feat for a machine with a wet weight exceeding 380kg.
Technical Overview: The VNT70J Platform
The Voyager Custom is powered by a 1,700cc long-stroke, liquid-cooled, SOHC V-twin. Unlike its full-dress sibling, the Custom features a blacked-out aesthetic and a shorter windscreen, targeting the “performance bagger” demographic. The engine utilizes a single-pin crankshaft to provide that signature V-twin pulse, while dual counter-balancers and an electronic throttle valve (ETV) ensure the power delivery remains sophisticated and manageable across the rev range.
Maintenance Essentials
Lubrication System
To maintain the integrity of the hydraulic valve lash adjusters and the 6-speed overdrive transmission, the VNT70J requires high-quality semi-synthetic or synthetic oil. The capacity is 4.3 liters of SAE 10W-40. MotoSpecsLab recommends oil meeting JASO MA2 standards to ensure the wet clutch operates without slippage under high torque loads.
Ignition and Electrical
The 1700cc powerplant utilizes high-performance NGK ILZKAR7B11 iridium spark plugs. These are essential for the lean-burn fuel mapping required for Euro 3 compliance. The electrical system is supported by a heavy-duty YTX20L-BS battery, necessary to provide the high cold-cranking amps (CCA) required to turn over the large-displacement pistons.
Chassis and Contact Patch
Handling on a bike of this scale is highly sensitive to tire condition. The VNT70J runs on a 16-inch wheel setup. For optimal stability, the front 130/90B16 should be maintained at 1.96 bar (28 psi), while the rear 170/70B16 requires a significantly higher 2.75 bar (40 psi) to support the integrated luggage and potential passenger weight.
MotoSpecsLab Editorial Verdict
The VNT70J is an over-engineered masterpiece of the early 2010s. While heavy, its electronic assists and liquid-cooled heart make it one of the most reliable long-distance cruisers on the secondary market. Strict adherence to the 4.3L oil capacity and specific tire pressures is non-negotiable for maintaining its balanced handling characteristics.
Frequently Asked Questions
Q: How often should the spark plugs be replaced?
A: Given the use of Iridium (ILZKAR7B11), they typically last 15,000 to 20,000 miles, but should be inspected every 7,500 miles for gap erosion.
Q: Can I use 20W-50 oil?
A: While 20W-50 can be used in extremely hot climates, Kawasaki specifically optimizes the VNT70J tolerances for 10W-40 to ensure proper flow to the top end during cold starts.