whats this noise

[no limit]

my quad has run excellent for 2 weeks now since the rebuild, but now it seems is you are at about half throttle and punch it, it makes a hammering noise like a hammer on the head, it only does it twice then stops. if its reved out its fine and if you are lugging it its fine, what is this noise and how do i fix it. i thought it was a ping so i started mixing 100LL av. gas is it and it never helped at all.

[duke416ex]

have you checked the valves, and made sure the timing was still good?

[no limit]

i set the valves twice and it still does it, how can you change the timing? it ran fine for 2 weeks or so after rebuild

what about the piston??

[duke416ex]

You set the timing with the cam gear, are you sure you aligned it right?

[no limit]

why would this problems have not come up in the first 2 weeks, i also thought timing but it was fine for so long.

[JDiablo]

what kind of camshaft are you using?

[400exredrider]

sounds like it may have jumped time

[no limit]

the cam is a stage 1 hotcam.

i rode it today and it was doing it more and more, i stopped and checked the oil level and as soon as i pulled the cam off oil poured out i have no idea why there was so much. i changed the oil and the filter and only put enough oil in so that it barely touched the dipstick, i started it and let it idle for 30 sec. and checked it again and the same thing happened it was right full, the more i let it run the higher and higher the oil level got.

any ideas about this?

[plkmonster2]

It sounds like the return for the oil is clogged. You may have no oil in your bottom end, and things may be getting dry. It sounds as if all the oil is getting stuck in the top end, and being forced into the oil tank through the hose.