not sure what all he does on the 490.s . this 250 has extensive intake porting, yamaha rod,that is 2MM shorter then stock, base of cylinder cut 2MM. cut head..My base gasket looks more like a 83-250 then a 81..Bike runs really good. He is the best maico engine builder in the states in my opinion..
its no big deal. It does have a Eric Cook stage 4 motor. Look at the cylinder base on the intake side. built up with weld and ported. Very large intake tranfers.Yamaha rod also. type 55 bing..
Thanks paul..
Bill you mention it has a Eric Cook Stage 4 Motor! What are the various stage setups or mods per stage nd do the 490 motors have a equivelent modification stages? Can you elaborate? Eric assembled my 490 Motor in the US prior to it being sent here and I found that the port chamfering horrendous and had Serco locally redo them.
