I copied this from another forum, basically it would be a good ideal to take all hoses off and make sure they’re clean and free-flowing, then make sure the valve opens and flows with 12vdc applied. Whether or not the ecu is telling the valve to open could be harder to test. Maybe a test light wired in and motor brought up to 7000plus;
The ECU on your engine, cannot regulate the opening and closing of the VES valves without all the components working properly, including the VES exhaust valve solenoid. Just removing the valve will not fix the VES system.
1. You may have an electrical fault in the wiring going to the solenoid.
2. It appears the exhaust valve solenoid has not been functioning properly for a while. Use some carb cleaner, spray it in the inlet and outlet nipples, let it sit, and then try to clean it out. The exhaust valve solenoid changes from open, at lower engine speed, to closed, at higher engine speed. Rig up some jumpers to something with a battery and test that the valve actually transitions between open and closed, when 12 volts D.C. is applied and disconnected. The electrical resistance across the exhaust valve solenoid, should be approximately 15 ohms. If the exhaust valve solenoid does not change between open and closed, you will have to replace it.
OPERATIONS on Pro-Ride models:
Solenoid energized ON, the vent is open, to release combustion chamber pressure behind the VES bellows.
Solenoid OFF (no electrical signal), the vent is closed. If enough combustion chamber pressure builds up, the bellows will lift the guillotine valve against spring pressure, and go into high speed exhaust port configuration.
There are three control situations for the solenoid:
At idle the solenoid is OFF (not energized), to avoid VES guillotine flutter. The vent is closed, but there is not enough combustion chamber pressure to allow the bellows to overcome spring pressure.
At engine speeds above idle, the ECU turns the solenoid ON, and the vent is open. VES guillotine stays in low speed position.
Based on a combination of inputs and rules involving higher engine rpm, the ECU turns the solenoid OFF, the vent closes, and combustion chamber pressure to the bellows overcomes spring pressure and raises the VES guillotine to high speed position.