04' CRF450R bottom end noise

[The Bomber]

I did a search for this. My buddy has this bike. He was racing it in a hare scramble, it was hot an he bounced the rpms off the rev limiter a few times. On the water pump side of the motor it now has a light clacking sound. The valves are good, we just replaced the water pump shaft, seals and bearing. The clacking sound is louder than my 05'450X. Everything behind the primary cover looks good. I looked for excessive play, odd wear on the gears etc. It seems like it is comming from the water pump area. I am going to buy a stethoscope and go at it again.

Any ideas? He wants to run it until something cuts lose. I advised him against it. It is in the area where it could be a crank bearing.

[oakhillbiker]

timing chain slap ?

[specialkcrf]

check the oil filter for metal shavings could be the crank. mine was making wierd nouise and would still start thats what happend to me

[The Bomber]

its on the waterpump side, so I don't think its the timing chain. The motor feels tight when you ride it. I will check the filter.