Purpose, Function
By lengthening the exhaust passage, the transmission of exhaust pressure waves to other cylinders can be delayed, and the amount of gas exhausted from a cylinder and forced back inside the combustion chamber is reduced By reducing the residual gas, the temperature inside the combustion chamber is reduced and the occurrence of knocking even at a high compression ratio is inhibited.
Construction
The exhaust manifold is installed to the rear of the engine. In addition, the catalytic converter (WU-TWC) is integrated (WU-TWC).

When the No.1 cylinder is at the intake stroke, the No.3 cylinder is at the exhaust stroke. By inducing the high temperature gas exhausted from the No.3 cylinder into the No.1 cylinder, the high temperature gas in the No.1 cylinder remains. If the amount of residual gas is high, the temperature in the combustion chamber rises and knocking can easily occur. With the 4-2-1 exhaust system, the transmission of exhaust pressure waves between each cylinder is delayed by the long exhaust pipes.

Exhaust System Removal/InstallationClock Spring Adjustment [Two Step Deployment Control System]
1. Set the front wheels straight ahead.
CAUTION:
The clock spring will break if over?wound. Do not forcibly turn the clock
spring.
2. Turn the clock spring clockwise until it stops.
3. Turn the clock spring counterclockwise approx. 2 turns.
4. Align the mark on the clo ...
Cowl Upper Plate Removal [Panel Replacement]
Symbol Mark
Removal Procedure
1. Drill the 9 locations indicated by (A) shown in the figure.
2. Drill the 2 locations by (B) from the front wheel housing side shown in the
figure.
3. Drill the 2 locations indicated by (C) from the inside shown in the figure.
4. Remove the cowl upp ...
Front Door Key Cylinder Removal/Installation
1. Disconnect the negative battery cable..
2. Remove the service hole cover.
3. Detach the screw from the front door key cylinder.
NOTE:
The screw cannot be removed because the front outer handle bracket has a
stopper which prevents the screw from falling.
4. While pre ...