ka driveline vibration

[sx moneypit]

I installed a lightweight flywheel and new clutch on my car a few months a go.Problem is that it has picked up a buzzing type vibration on down shifting from about 2500 to2000 rpm.It is driving me crazy.Could it be the loss of mass in the flywheel? Is this a common problem or is it just me?Thanks for any help on this.

[nightsauce]

did ya use air tools or a torque wrench to tighten the flywheel bolts? Bolts backed out caused an initial vibration followed by a grinding followed by boom.

[sx moneypit]

The bolts were torqued with a Snap on torque wrench and installed with red Loctite. I hope they are still tight! Thanks for your input on this!