Probably could help if you told us details about the bike in question.
If you have tubeless tires mounted on tube type rims, seating the tire properly on the rim can take extra care that modern tire jockeys don't always perform.
Lift the front end so that the wheel will spin freely. Watch as the tire spins and see if there are high points on the tread as it spins. If the tire is out of round, or if the tire is not seated on the rim correctly, the tire may roll out of round and cause vibration.
Also, as the tire spins, look on the tire near the rim and fins a raised line on the tire. This line should be the same distance from the rim all the way around the tire. Check both sides. If there is any variation, you can expect some kind of issue with vibration at speed, regardless of how well balanced the tire is.