Plugs covered in scale and deposits?

[HiWaYman92]

Pulled my plugs after my first 500 miles on my sled. These were in for the break in pre mix riding too. Plugs were decent cocoa color, but covered in chunks of scale/deposits. Any idea why this is? Is it normal?

 

[m8magicandmystery]

could have been from the premix and injection phase that has stayed on the plugs...i would stick new ones in and see if you repeat...but i think it may not have the same deposits anymore