Thanks Brian!
I just finished to put everything back.
No more noise!!!

But I didn't have a chance to do a test ride, today it is rainy and cold, only 45°F. Tomorrow it will also be cold, 39°F. But Friday is suppose to be not to bad, near 60°F with a mix of sun and cloud. That will be good for a road test!
I don't know if the jetting will be ok with the 836. Right now the carbs, jets, airbox are stock. IF I can ride a little bit, I will be able to look at the spark plugs.
I took many pictures of the build. When I'll have some spare time, I'll do a thread on that build!
Thanks for all your comments!