ncy valve springs or titanium retaners?

[Johnny 5]

Has any body used these ncy 11,000 rpm plated springs.
I am concerned about the A12 cam I just put in last week.
The buggy runs good up and down the street, not sure about longer runs.

I was going to buy titanium retainers for $45, but not sure if I should just get stiffer springs instead.

I just dont want to wear the valves cam rockers with over kill springs,
and do not want to bend the valves or break the motor.

Any ideas?

[xlint89]

As I noted before in the other thread, Tom says those NCY 11k RPM springs really aren't much better than stock. That's why he uses a custom spring manufacturer.

You'be be better off using the Tit retainers IMO to save weight.

However, your A12 is focused on low to mid RPM power. You shouldn't be revving your motor that high with that cam. If you were using a cam focused on top end, yes.

I floated/bent my valves because of the A11 cam, and my external gearing was too high. So my RPM was really high, and the kart really didn't make much speed. I KNEW what I was doing when it failed. In other words, I basically murdered my motor. Hopefully anyone else that hears the engine screaming and doesn't have much speed to show for it would be smart enough to NOT continue pushing it like that.

[Johnny 5]

Thanks xlint89 for helping me make up my mind. I did already put the stock 31t on and the take off from a stop is a bit slower but at a 5mph roll it pulls great and cruise rpm is down about 1000 rpms.
The tit retainers are for extra insurance to keep the valves off the piston. With the 183cc motor I had to take .015 of an inch off the head to get the timing chain from binding when the cam was tightend. With the cylinder 1.6mm spacer and 2 base gaskets the deck clearance was .025 and the head gasket is .010 for a total of .035.
It is tight but last trip with the stock cam was running 7200rpm no problem, above that it would cut out wich I bielive was the cdi going bad or valve float?. So with the orange cdi ran good just kept an eye on the rpms and stayed below 7200 for fear of blowing up the motor first trip.
I tried to find a 35t sprocket with a 58/80mm bolt pattern and have given up so the 31t will have to do.
Before we put the 39t sprocket on the blue 150 with a stock motor with home port job on the head it would go fast enough to make me want to slow down,probally close to 40mph. It would labor to go up hills with two riders, but with no passenger it hauled butt.
The 39t sprocket was great on take off and climbed good with a passenger but top speed with the garmin was 29 mph motor screaming (didnt have a tach yet) probally 8000 rpm plus.
I am going to keep the rpms down to 7000 on this motor to be safe.
The tach is a TTO from trail tech cost 30buck with shipping, a very good tool for tuning.

Sorry for the long post just like to get the info out my head and share my results.

[GX150]

The A12 is considered a torque cam so the lift is not that extreme, but the duration is longer. You need to consider stronger valve springs if you you use a higher lift horsepower cam.