Motorcycle Repair: 02 CRF450 Valve Seats, valve seats, valve adjustment

Question
Replaced valves but did not have valve seats machined.Getting intermittent backfiring. Thinking I need to have valve seats machined.

Amy idea as to the cost to have the valve seats machined or is it more cost effective to just replace the head?

Answer
Find a dealer with the correct drill bits for the valve seats, just ask them if they do it in-house or send it out.  Find one that does it in-house, pull the head and bring it in... it shouldn't cost more than 1hr labor, if that.

However, it's more likely the backfiring is from the valve adjustment..ensure that is correct before continuing.

Anthony
'Ride Today - Live Again'