How does yz250 power valve work?
The power valve is a movable flap located on the cylinder exhaust port of a two-stroke engine – where burnt gasses are flushed out of the cylinder. This helps the engine generate torque at low speeds. As revs build, the flap gradually opens, expanding the size of the exhaust outlet for greater top-end power.
Does a CR500 have a power valve?
The CR500 engine has an exhaust power valve to smooth out the power delivery but Honda doesn’t use them on its four stroke dirt bikes.
What is a variable exhaust system?
translated from. A dynamically variable exhaust system provides for maximum efficiency of an internal combustion engine (30) by including an exhaust control device (35) which is operated by a control mechanism (33) and managed by a control unit (32).
Can you clean a 2 stroke power valve without removing the cylinder?
(Note: Some power valve designs allow for cleaning without removing the cylinder but most 2-strokes require it.) The cylinder houses the power valves which look a bit like airplane flaps (see diagram). You’ll need to remove the bolts to extract the valves. But check your service manual before removal.
What’s the best way to clean power valves?
Some valves only install a certain way so jot down notes and/or take photos as you remove and disassemble. Once removed, scrape off any carbon build-up using steel wool or a stiff toothbrush then apply contact cleaner or other similar solvent (brake cleaner, gasoline) to finish the job.
Can you adjust the power valve on a Honda Accord?
You can adjust most power valves for lower or high-end speed but not all manufacturers use the same method. KTM uses a tensioner and spring contraption while Honda uses a cable operated system. Adjusting the valve enables you to increase power on the bottom or top end depending on your preference.
