6/11/2014 · Too much clearance and the engine will be noisy and you will effectively lose valve lift. Too tight and the bike may be hard to start. Also, tight valves , as is little to no clearance, will run hotter and may bleed off compression and lead to power loss. When the valve closes, it mates with valve seat in cylinder head to dissipate heat.
6/4/2018 · After riding it more I attribute the flat power feeling to the powervalve openening very quick instead of a steady transition like the X spring provides. Not quite happy with the results I reinstalled the X spring but this time I took out the extra washer I installed with the yz spring and one original 0.08 washer. So I had a total of 3 0.08 …
4/9/2009 · i recently brought a yz250 96 does anyone now how to adjust the exahaust valve as im using the bike in the woods and i need to calm it down a bit im trying to get a bit more torque. i need the valve to open later in the revs if possible????? ive rode a rm250 for years and the power valve on that was easy to adjust the yz iz much faster, 4/9/2016 · Replacement YZ 250 power valve spring, allows a smoother power delivery for improved low to mid throttle response. Suited to motorcross and enduro applications. Price: $35 AUD. The installation requires a small amount of knowlege of engines as you do need to pull the clutch side casing off. If you can do that youre right to go.
View and Download Yamaha 1994 YZ250/LC owner’s service manual online. 1994 YZ250 /LC motorcycle pdf manual download. Also for: 1994 yz250f/lc.
What Is a 2- Stroke Power Valve ? A 2- stroke power valve is nothing more than a piece of metal slid into the engine’s exhaust port. Its primary function is to regulate the size of the exhaust port, thus enabling the engine to deliver controlled power throughout the rev range. Back in the day, two-stroke engines had very limited power bands.
