4 speed problem

"New" doesn't necessarily mean "good". Several folks here found that out recently. Old clutch did not have the "shimmy/vibration"?
What condition is the pilot bushing in?
Some things you might check...…….
Loose bell/trans mounting bolts.
Fat spot on the disc.
Fingers not adjusted to same height. Bearing not contacting/releasing fingers evenly, or not attached to the fork properly.
Fork pivot bent/worn, or fork not completely on pivot.
Off center/twisted clutch plate in the cover.