You might have to replace the exhaust valves at this point. The reason for that is that the YFZ has Titanium valves that can not be serviced if the seat face is damaged, but it would have to be inspected first to know if it needs valves or not.
We can do the valve job for you. If you ship it to us or drop it by, we can turn it around in a day if it only needs a valve job.
A competition valve job will run you $105.00 plus return freight if needed.
ATP Racing
407-880-3171
atpracing@earthlink.net
