Specification:
- Displacement(c.c. / cu.in.): 8.67 c.c / 0.529 cu.in  
- Bore(mm / in.): 22.5 mm / 0.886 in 
- Stroke(mm / in.): 21.8 mm / 0.858 in 
- Practical R.P.M.(R.P.M.): 2,000~21,000 
- Output(BHP/RPM): 2.1 BHP / 17,000 RPM 
- Weight(g/oz): 380 g / 13.40 oz 

Introduction:

Extreme Power Helicopter Model Nitro Engine

REDLINE is a new helicopter engine line from Thunder Tiger. Higher performance and extreme power in a compact-size engine with yet larger displacement and awesome power. The RL-53H is a fantastic nitro powerplant for your 50 class R/C helicopter.

The RL-53H engine features XC2 extreme composite coating with nano-technology from Japan for longer engine life, a special criss-cross pattern etched on the sleeve wall for much lower friction and an oversized heat sink head. These exclusive RL-53H's features deliver much more reliable power and higher torque through the full range of RPM.

The brand-new carb design is mounted on the crankcase with a very effective heat insulator to keep the carb working at stable temperature under all conditions.