Strange vibration???

[Hairball]

I just finished a second build for my lady...

- 09 Specialized Stumpjumper.. 15" frame
- BBSHD
- Luna 42 eclipse
I dumped the old Juicy 5 hydraulic for some BB7's

Any hoo, I take her for a spin and there is a vibration in the mid-range of the RPM's ...
For reference purposes only - If the RPM range is 1 to 10... The vibration happens in the 5-7 range when throttling in the first 4 gears... then it seems to go away as I shift up to 10th gear.

There is also a buzzing noise when it vibrates down in the motor area... It's a pretty serious vibration that travels through the whole bike.
My chainline looks good,
The motor is tight, I checked all the screws and mounts... Everything has Loctite.

I'm at a loss.

Any ideas on what I might have missed?

 

[6zfshdb]

What tires are you using and what type of surface are you riding on? Does the problem lessen with a change in tire pressure? I get mid range vibration on a couple of my MTB's when running on certain asphalt surfaces. Dropping the TP by 5 pounds or so usually solves the problem.

Can you duplicate the vibration when running the bike on a stand?