NCY 1100-1284 GY6 150cc Valve Springs On A 50cc
Feb 16, 2010 7:23:54 GMT -5
highmoose and TurboTyler like this
Post by 90GTVert on Feb 16, 2010 7:23:54 GMT -5
On to the valve springs...
NCY 1100-1284 "EP Titanium Valve Spring"
Here are the stock 50cc GY6 valve springs with the NCY GY6 valve springs.
You can see that the NCY springs are slightly longer, but here are the measurements I got.
--------------Diameter-----Length----Weight
Stock Outer :__22.10mm__33.45mm__15.4g
NCY Outer :___22.20mm__35.53mm__16.5g
Stock Inner :__16.00mm__30.09mm__6.95g
NCY Inner :___16.01mm__31.90mm__7.2g
I can't say I'm too impressed with the valve springs either. After hearing Kliff mention companies putting a coating on stock valve springs and selling them as performance springs, these numbers make me wonder. The rainbow coloring also makes me think it may just be a titanium nitride or titanium oxynitirde coating. These springs are actually heavier than stock. Real titanium springs should be lighter than steel springs, even if they are slightly longer and just barely larger in diameter. They are a bit longer, and I suspect they may provide more pressure, but I wonder if they would still be longer than a set of stock springs that were fresh out of the box?
I popped the springs outta the 72cc head that has very few miles on it, just to see the difference.
72cc Outer :___22.10mm__34.18mm__15.6g
72cc Inner :___16.06mm__31.84mm__7.2g
I had a big pin lying around for connecting tow behind lawn equipment. It has a nice built in washer on the top and a handle to make this easier. It's got a hole in the bottle for a cotter pin or clip... or in this case a clothes hanger. I slid the valve springs up onto it and then put a large washer under the spring.
I put that through a section of a loading ramp that has holes in it and is plenty beefy to support the weight I'm working with. Then I attached weights to the bottom via the clothes hanger through the pin.
I'm too lazy to attempt to measure installed height of the valve springs and try to achieve that by the exact amount of weight, so I did something pretty basic. I started with a stock spring and attached 35lbs to it. I then measured the height of the spring. Then I replicated that height on the NCY spring. I only did the outer springs. The pin is too large for the inners.
72cc Outer : 3/4" @ 35lbs
NCY Outer : 3/4" @ 40lbs
In lbs./in.:
72cc --- 46.7
NCY ---- 53.3
Therefore the NCY is 14% stiffer.
So the NCY is delivering a little more spring pressure. Considering Reg can't seem to float valves at 11,700RPM (granted he probably didn't have quite the same ramp angles) and I would be amazed to see 10,000RPM, I don't see these springs being worth the money unless you are getting crazy with the cam and/or RPM.
These springs do install on a 50cc head just fine. They worked fine for me, but I never pushed the limits of the valve springs.
NCY 1100-1284 "EP Titanium Valve Spring"
Here are the stock 50cc GY6 valve springs with the NCY GY6 valve springs.
You can see that the NCY springs are slightly longer, but here are the measurements I got.
--------------Diameter-----Length----Weight
Stock Outer :__22.10mm__33.45mm__15.4g
NCY Outer :___22.20mm__35.53mm__16.5g
Stock Inner :__16.00mm__30.09mm__6.95g
NCY Inner :___16.01mm__31.90mm__7.2g
I can't say I'm too impressed with the valve springs either. After hearing Kliff mention companies putting a coating on stock valve springs and selling them as performance springs, these numbers make me wonder. The rainbow coloring also makes me think it may just be a titanium nitride or titanium oxynitirde coating. These springs are actually heavier than stock. Real titanium springs should be lighter than steel springs, even if they are slightly longer and just barely larger in diameter. They are a bit longer, and I suspect they may provide more pressure, but I wonder if they would still be longer than a set of stock springs that were fresh out of the box?
I popped the springs outta the 72cc head that has very few miles on it, just to see the difference.
72cc Outer :___22.10mm__34.18mm__15.6g
72cc Inner :___16.06mm__31.84mm__7.2g
I had a big pin lying around for connecting tow behind lawn equipment. It has a nice built in washer on the top and a handle to make this easier. It's got a hole in the bottle for a cotter pin or clip... or in this case a clothes hanger. I slid the valve springs up onto it and then put a large washer under the spring.
I put that through a section of a loading ramp that has holes in it and is plenty beefy to support the weight I'm working with. Then I attached weights to the bottom via the clothes hanger through the pin.
I'm too lazy to attempt to measure installed height of the valve springs and try to achieve that by the exact amount of weight, so I did something pretty basic. I started with a stock spring and attached 35lbs to it. I then measured the height of the spring. Then I replicated that height on the NCY spring. I only did the outer springs. The pin is too large for the inners.
72cc Outer : 3/4" @ 35lbs
NCY Outer : 3/4" @ 40lbs
In lbs./in.:
72cc --- 46.7
NCY ---- 53.3
Therefore the NCY is 14% stiffer.
So the NCY is delivering a little more spring pressure. Considering Reg can't seem to float valves at 11,700RPM (granted he probably didn't have quite the same ramp angles) and I would be amazed to see 10,000RPM, I don't see these springs being worth the money unless you are getting crazy with the cam and/or RPM.
These springs do install on a 50cc head just fine. They worked fine for me, but I never pushed the limits of the valve springs.