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440 help
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Posted by: CSR400EX

i just got my 11:1 wiseco 440 kit installed and running. when i first started it, everything sounded really good. and now after a few hours of break-in, it started making this nasty sound past 1/4 throttle, like the valves are hitting something, but when it idles or before 1/4 throttle, it sounds great. i am wondering what the problem may be

Posted by: Sparky_20

is it a metal on metal, knocking, clunking? It could be pre-ignition. Also did you get your head and or block decked?

Posted by: JW450R1

I see u also have a hot cam.They are noisey.Is the noise a taqpping type noise from the top end of the motor?

Posted by: CSR400EX

yes my cylinder had to be decked when the sleeve was installed. as for the noise it is very loud like metal to metal tapping like the valve is barely hitting the piston or something

Posted by: CSR400EX

would a blown head gasket make noise like that because there is some leakage between the head and cylinder on the right side.

Posted by: JW450R1

why is there leakage and what is leaking

Posted by: Ruby Soho

does it sound like metal tapping when you blip the throttle?

also, did you go with HD studs ?

Posted by: CSR400EX

Ruby, yes that is exactly what it is doing and no i tdidnt use the HD studs, but i got a set on order.

Posted by: Ruby Soho

yup thats a blown head gasket. the studs will fix that problem. when you order the new gasket get either the Cometic MLS (multi layer steel) or the factory gasket.. there the 2 best. i blew 2 gaskets, put in the studs and a factory gasket and its doing great

Posted by: CSR400EX

thats what it was. i took the top end off and i could see where it was blowing through. i just ordered the HD stud kit from gt thunder, and now im back to a stock cylinder