engine noise

[skully440ex]

my 440 ex makes a clatter noise when it is hot when you snap throttle open quickly. it is 11 to 1 comp. im running 93 octane mixed with race fuel,the valves are adj. properly. my buddie sez its timing chain slap but wouldent it do it all the time,not just when hot? any thoughts or comments would be great.

[450Honda23]

I would have to say its the timming chain too. Unless maybe something broke inside and is pinging around in the like a pinball machine but if that was the case I think maybe eventualy it would stop and then the motor would lock up. Try ajusting the timing chain. You may have to get a new one because it is stretched. There like 30-40 bucks for a new one.

[Ruby Soho]

head gasket? check around it and look for leaks

[svahle]

If you go to replace the timing chain, do a search. Many people are using the heavier timing chain from either the 450r or the crf450. I cant' remember which and was too lazy to search (sorry). But with a 440, I would go with the heavier timing chain and not have to worry about it for a while.

EDIT: Okay, I did a search and its the CRF450 timing chain. Some say use one for a 2002 model, but I think the part numbers are the same for other years.

[skully440ex]

hey thanks for the input. the head gasket is fairly new,pretty shure its the timming chain now. i will definatly check out getting the heavy duty chain. thanks agin.

[Punk'd]

Yeah, im putting my money on the chain. It would make sense if it only slaps when hot. (Heat expands) Causing the chain to stretch?

Just my 2 cents.

Hope you get it figured out.

[xcracer416]

i do agree with everyone else on the timing chain. mine done the same thing. the crf timing chain is the way to go, cheaper than everyone elses hd chain and is just as good. check your guides also, mine was wore badly when it started doing it.