Maintenance & Technical > KX500 Original
Sleeve Transfer port matching
3Razors:
Good points guys. This fmf cylinder is a mystery. I'm still not a fan of the sleeve. I think I'm going to throw on my virgin stock cylinder for comparisions sake and try it. The exhaust looks small for a 500, seems it would be hard to modify with guillotine valve in the way. How many mm's do tuners usually raise transfers on these over stock? I don't want anything that is too peaky in rpm though.
kaw rider:
razor
yes the exhaust does look small but not for the rpm range the engine was design for. It sucks that to make these cylinders run great you have to drop some coin. But porting or cylinder layout is only small part of the puzzle to makes these run good.
3Razors:
--- Quote from: kaw rider on September 18, 2010, 06:42:51 AM ---razor
yes the exhaust does look small but not for the rpm range the engine was design for. It sucks that to make these cylinders run great you have to drop some coin. But porting or cylinder layout is only small part of the puzzle to makes these run good.
--- End quote ---
I agree..I feel to truly make this cylinder run a hard a new custom pipe needs to be made. My friend has a LT500 (same bore/stroke as KX) that is putting out 90+hp to the rear wheels on race gas. It's nothng really exotic either..custom big volume pipe, right porting/head work, and 44mm carb. Here is the dyno chart of it, it was on a dynojet inertia 248 model. Notice how it has a nice umbrella power curve...not peaky like most the high hp 500 builds. The other pic is of the pipe, it is monster..like 7-8 inches in diameter and larger stinger too. I feel the kx can at least make the same modified hp as the lt if not more as the kx has a better port layout.
kaw rider:
razor
the torque has a nice 2k range window, great for transmission rpm drop. I don't look at hp because you can be low or higher then that with almost same torque numbers. I like to shout for a 3k torque range. I know jerry and robert makes good power.
GREENKAW24:
--- Quote from: 3Razors on September 18, 2010, 05:33:35 AM ---Ok so here's some pics. Turns out the transfer and exhaust ports are the same size as stock. The intake ports have all been opened up quite a bit. The roof height on the transfers is higher than the sleeve by 1.5mm. From the top of the transfer to top of cylinder on both stock/fmf cylinder is roughly 69mm. Now my understanding is that all this portwork on the intake is basically useless because the transfers/exhaust ports are same as stock?
--- End quote ---
The port work isn't useless, because even though the port heights are the same as stock, this cylinder will flow better than a stock one. The midrange will be better than stock on that FMF cylinder.
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version