Maintenance & Technical > KX500 Original
crank stuffer
Brett:
Aren't those conrods just for 4 strokes?
Shouldn't exhaust ports be flat on the top to make sudden pulse.
bigbellybob:
--- Quote from: BDI on January 02, 2008, 05:35:45 PM ---I guess a upside down triangle is a bad description It is a trapezoid. The idea is to have the left and right port walls get slightly closer together towards the bottom. when the piston first starts to uncover the port the gasses are under high pressure so it comes out fast but as more and more of the port is uncoverd the pressure drops and the gasses slow down. the idea is if the port narrows towards the bottom the gasses keep moving fast even though the pressure is droping.It's like when the river is wide the water flows slow but when the river narrows the water moves faster. Yes I'm sure the port has to flow less but this should make great bottom end torque and mid range. I want to make up for this with larger secondary exhaust ports but I do not think this would have that great of an impact on top end because we are not talking about making the port a lot smaller and by the time the port opens all the way It has allready done the vast majority of its flowing.
--- End quote ---
BDI is this close to what your talking about. the top would be stock and the bottom a BDI mod.
BDI:
--- Quote from: bigbellybob on January 03, 2008, 09:30:16 AM ---
--- Quote from: BDI on January 02, 2008, 05:35:45 PM ---I guess a upside down triangle is a bad description It is a trapezoid. The idea is to have the left and right port walls get slightly closer together towards the bottom. when the piston first starts to uncover the port the gasses are under high pressure so it comes out fast but as more and more of the port is uncoverd the pressure drops and the gasses slow down. the idea is if the port narrows towards the bottom the gasses keep moving fast even though the pressure is droping.It's like when the river is wide the water flows slow but when the river narrows the water moves faster. Yes I'm sure the port has to flow less but this should make great bottom end torque and mid range. I want to make up for this with larger secondary exhaust ports but I do not think this would have that great of an impact on top end because we are not talking about making the port a lot smaller and by the time the port opens all the way It has allready done the vast majority of its flowing.
--- End quote ---
BDI is this close to what your talking about. the top would be stock and the bottom a BDI mod.
--- End quote ---
Yep just like that.
maddoggy:
brian, that makes good sense to me. i think you're on to something here. it could work, when are you going to try it? MADDOGGY
BDI:
As soon as I can find a good cylinder to build the way I want. It will probably be a while though because I want to build a stroker crank too and the cylinder will have to be built to suit the stroked crank.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version