Compcams Conical Valve Springs Press Release

Not much info in the press release here

http://www.enginelabs.com/news/new-prod ... e-springs/

but more on the web site here for those interested

http://www.compcams.com/whatsnew/NewsDe ... -197776087

Don't know if any are suitable for Nortons, but I expect we will soon see other suppliers also offering conical springs.

Ken

Thanks for that.

The first I heard of beehive springs was from/in connection with some GM V6 engines. I wonder why GM settled on a beehive shape as opposed to this cone shape. The harmonics would be different. So too would be the curve that describes the rate of change in the angle of the wire to the load as the load moves down the spring as it is compressed. Perhaps that is why CompCams designed their spring with a diminishing wire diameter from bottom to top. Lots of stuff to ponder.

Be interesting to see what Jim Comstock's testing in the spintron comes up with for these conical springs to suit our Nortons
I am interested as I am building a race motor ande looking at a rev limit of 8000 rpm

Regards Mike

xbacksideslider said:

Thanks for that.

The first I heard of beehive springs was from/in connection with some GM V6 engines. I wonder why GM settled on a beehive shape as opposed to this cone shape. The harmonics would be different. So too would be the curve that describes the rate of change in the angle of the wire to the load as the load moves down the spring as it is compressed. Perhaps that is why CompCams designed their spring with a diminishing wire diameter from bottom to top. Lots of stuff to ponder.

Click to expand...

I'm not sure why beehive springs surfaced before the conical designs. Most of the beehive springs I've seen on Nortons are the ones designed for the modular Ford engines. The first beehive springs I ever saw were for Chevy small blocks, but they were inverted from what we see now, with the small end at the seat, and the larger diameter at the retainer. They let you use a larger diameter valve spring using the stock spring seat area in the head. Be interesting to see how this all works out. Springs haven't really been much of an issue in Commando race bikes until the advent of ultra short stroke engines, which operate at much higher rpm. Lots of folks raced Commandos with 2S cams and stock springs with no problems. When S&W springs came along, they were good for pretty much any cam then available, but that was all at standard stroke sorts of rpms. The advent of short and ultra short stroke engines appears to have changed that.

Pneumatic springs, that's what we need.

Ken

Ken

There are definite advantages to some of the new spring designs besides the ability to handle high rpm.

The new springs have much higher spring rates without the friction induced problems of old double race springs.

A high spring rate allows you to use a low seat pressure and still avoid bounce due to the fact that the spring and retainer are low mass.

The high rate allows for a great increase in pressure as the valve opens which prevents separation of the valvetrain parts.

It has not been very long that a small lightweight single spring with a 300 lb rate or more has been possible. Even 15 years ago it took a massive single spring or dual springs to approach a 300 lb spring rate.

Now it can be done with a little single beehive or conical spring -that is still be able to survive without breaking due to improved metallurgy and manufacturing processes. Jim