Hyper R Stage Big Bore Kit 88cc Product # 01-05-3424

R-stage series is the only 50cc (FI) horizontal engine that can perform head tuning
SP Takegawa's traditional R-stage head technology is adopted, which enables high output performance that cannot be obtained with the stock head.In addition, the high performance injection controller allows you to maximize the performance of the R-stage cylinder head.
■R stage head
Based on the standard head shape, large diameter valves, intake: 26mm / exhaust: Adopted 22.5mm.
(Stock valve is intake: 20mm / exhaust:16mm)
This is SP Takegawa's original cylinder head which was developed by constructing the optimum valve pinching angle, combustion chamber shape and port shape along with the adoption of large diameter valves.
By combining the improved intake and exhaust efficiency with the increased displacement and the high performance injection controller, it is possible to achieve a higher output than with the stock head.
port
The port diameter of the stock head is 20mm for both intake and exhaust, whereas the R stage head has a 20mm port diameter for the intake and exhaust: 24mm / exhaust: Larger diameter of 20mm.In addition, the adoption of a 3-dimensional port shape, combined with the larger diameter of the valve and port, makes it possible for more intake and exhaust gases to flow smoothly.
The weight increase due to the larger diameter of the valve is kept to a minimum by waist machining.
Valve Spring
The single valve spring with unequal pitch (2-stage pitch) is adopted for the best spring rate for R-stage head, and it prevents the surging at high rpm.Durable steel valve spring retainers are used
■Cylinder / Piston
Cylinder
The cylinder is an all aluminum ceramic plated cylinder.It is a cylinder with excellent durability, airtightness, and heat radiation.
The cylinder is equipped with an oil outlet to the oil cooler.
Piston
The piston skirt is coated with molybdenum to ensure good initial adhesion to the cylinder.
■FI CON PLUS (Large capacity injector included)
FI CON PLUS has a 3-dimensional fuel map inside, which is calculated at high speed based on the signals from various sensors, and can perform the best fuel injection according to the engine situation.In addition, not only the fuel injection circuit but also the ignition system circuit is built in, and the ignition timing is optimized according to the R stage.
With these modifications, the ECU can be used up to higher rpm than the rev limit of the stock ECU.
In spite of the high performance of FI CON PLUS, the fuel correction from the basic map (16 steps from -10% to +20%) and the limiter speed setting (16 steps from 7000 rpm to 16000 rpm) can be easily set by simply turning the rotary switch of FI CON PLUS with a screwdriver.No complicated PC connection is required.
■Hyper R Stage Big Bore Kit 88cc
Kit Configuration
R stage big bore kit 88cc with FI CON PLUS (injection controller), air filter with high intake efficiency, 16T drive sprocket to change the reduction ratio and spark plug.