Maintenance & Technical > KX500 Original
KX-500 Compression Release Mod! Easy Starting!!!
Rowdy-Yates:
Ive used Wiesco's in every bike I have owned!
doordie:
I`m trying just now PROX in my MX-bike. :wink:
It`s lighter ,but don?t know how it last(only 4 hours on it) :?
//doordie
Brett:
The issue with forged pistons of this diameter 86mm + is that when forging it is basically a big dick of one piece that gets pushed into the ally blank. This method is perfectly fine and give great grain flow following the shape of the piston but being one piece has cannot give the webbing that a casting can. A casting is often a five piece inner core that after being cast they get removed in a certain order. due to this they can give very rigid design pistons with all the webs they have internally. Forged pistons are perfect for 4 strokes due to pistons being very short and they have internal webbing as they don't have to seal of ports with the skirt. Generally most racing 4 strokes have the gudgeon pin nearly touching the oil ring. From many two stroke race engine builders i have spoken to they all choose pro-x pistons for the big capacity two strokes as they don't go out of round the wrong way. Cast pistons being more rigid and often less ductile material which is more likey to shatter rather than oblong. Cast pistons are also prone to shrinkage porosity in the heavy sections around the pin bosses. You will get many hours out of a 500 piston due to the fact they put out stuff all specific power and also rev stuffall. They reckon the hand grenade style racing 450 4 strokes these days have less piston life than a 250 twostroke as they are revving so hard and everything is on the limit to try and get as much power as a twostroke.
Timbowe:
speaking of high reving 4 strokes, a dude from round here got shot of his CRF450 cause it stretched the valve stems! Not only once, 3 times!! A young chap I was talking to at the ride yesterday, said to me I,m saving up to buy one of those in a few years second hand. I told him there will be no running second hand ones worth buying...
quincyman:
--- Quote from: Kawadougie ---Here you go. This is amazing. The compression release works. The mighty KX500 now starts as easy as a 125. You pull the lever and it kicks through like nothing and usually starts first kick. If you look at the photo, it is installed about an inch from the top of the cylinder. It still has enough compression to fire. I even put in the thinner head gasket. Best money I've ever spent. I was looking at buying a 250 but now I'm completely happy with my 500. :o
--- End quote ---
Now that you have had this mod for a while, what do you think of it? Still no problems? I'm getting ready to make the plunge. :?:
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version