400ex mod ?'s (carb/pipe?

[400exrider_88]

i bought a 426 ex last year and im just now getting it running right...

the carborator looks like it has been bored... is this possible? its the stock carb and the inside has a shaved look
the pipe (trinity stage IV) has been cut in 1/2, is this for added power??

i replaced the head and all topend gaskets, including the seals for the valves. it is still leaking into the topend through the valves, what should i do? also, a puddle of oil is forming in the area the spark plug goes, why is this still leaking with new gaskets?

im also looking for a +2 or +4 rear axle for this atv if anyone has one.
thanks

[dariusld]

1. carb-Probably not.
2. Pipe-Mainly for looks or maintainance issue
3. New head is leaking ????
4.Your valve cover might be leaking

[rob_990]

not sure about the carb but a shorty pipe does perform better than a regular slip on.
i get a little oil by my vales too. im pretty sure its normal are they adjusted right? hows the oil getting by the plug? is it from the head cover gasket of is it coming through the spark plug hole?

[rcatvrider]

It is possible to bore a carb.