| Component | Specification |
|---|---|
| Engine Oil | SAE 20W50 (2.8 L) |
| Front Tire | MH90-21 54H (30 psi / 2.07 bar) |
| Rear Tire | 200/55R17 78V (40 psi / 2.76 bar) |
| Spark Plugs | 6R12 |
| Battery | 65989-97C |
The 2007 model year marked a significant engineering milestone for Harley-Davidson: it was the first year the Softail Custom (FXSTC) returned to the lineup after an eight-year hiatus, debuting the then-revolutionary Twin Cam 96B engine. This counter-balanced powertrain, paired with the 6-speed Cruise Drive transmission, transformed the FXSTC from a vibrating legacy machine into a refined long-distance cruiser, capable of modern highway speeds without the fatigue of excessive mechanical resonance.
Technical Engineering Analysis
At the heart of the 2007-2010 FXSTC is the 1584cc (96 ci) V-Twin. Unlike the rubber-mounted engines in the Touring or Dyna lines, the Softail engine is rigid-mounted to the frame. To compensate, Harley-Davidson utilized internal counter-balancers (the ‘B’ designation) to negate primary vibration. This allows for the classic ‘hardtail’ look while maintaining rider comfort. The 200mm rear tire was a bold design choice for the era, necessitating a specific swingarm geometry to handle the increased rotational mass without compromising the lean angle.
Maintenance Guide & Lubrication
For optimal thermal stability in air-cooled V-Twin environments, MotoSpecsLab recommends SAE 20W50 synthetic motorcycle oil. The system capacity is 2.8 liters. Given the high operating temperatures of the Twin Cam 96B, oil integrity is paramount to prevent ‘sumping’ and premature wear on the hydraulic cam chain tensioners—a critical inspection point for high-mileage units.
Electrical & Ignition
The ignition system utilizes 6R12 spark plugs. These should be inspected every 5,000 miles for carbon fouling, which can occur if the EFI (Electronic Fuel Injection) system is running rich due to aftermarket exhaust modifications without a proper remap. The electrical system is anchored by the 65989-97C battery, a high-CCA (Cold Cranking Amps) unit required to turn over the high-compression 96-cubic-inch pistons.
Tire Dynamics
The FXSTC features a unique staggered wheel setup. The 21-inch front wheel (MH90-21 54H) provides traditional chopper aesthetics but requires a precise 30 psi (2.07 bar) to maintain tracking stability. The massive 200/55R17 78V rear tire must be kept at 40 psi (2.76 bar) to prevent uneven ‘squaring’ of the tread, which can lead to heavy steering in corners.
Editorial Verdict
The FXSTC/07 is the quintessential modern-classic Softail. It successfully bridges the gap between the raw, mechanical feel of the 1980s and the reliability of modern fuel injection and overdrive gearing. For the enthusiast, it remains one of the most customizable platforms in the H-D catalog, provided the maintenance schedule regarding fluids and tire pressures is strictly adhered to.