Vivid air won't fit without modifying/grinding the clevis attachment on the air can eye side due to the rebound dial wedged on the clevis and can't be turned. But can be easily remedied with the help of a bench grinder. Performance wise is same as Fox float X2. Only the later makes better due to "climb switch" lever. By the way, Firebirds are not spec for coil shocks with the exception on Push coil shocks.

 Hi, i would like to ask how well the vivid air shock perform with the firebird and if there a any issues with this combination ! Thank you in advance ! Cheers