[xr50racer]

the stock head configuration is not going to yield you the room to go with bigger valves. you cant just plop them in.



As for porting most "performance" shops as they call themselves fdpnt even have flow benches to check their work. I hate when a shop is calling themselves performance and they just go in hog out the port and dont know what they are doing.



Id take it to someone knownw for doing port jobs on a 50 head. DONT POLISH YOUR PORTS

 

[xr50racer]

is that just porting the stock head? does that include larger valves? which you will need. DOes that change your combustion chamber? alot of head jopbs change the combustion chamber utilizing a high dome piston to give way for clearence for valves that are larger. Im not thinking you will get that for 80 bucks.