2003 yz450F engine noise?

[chase1873]

I have been riding my bike alot the past week, and yesterday i started to hear a rattling sound. i would not be concerned because i no these motors are loud, but this is deff a new noise. it sounds like you took a big washer, slid it over a screw driver and just shook it around. anyone have any ideas of what it is?

[groundpounder450]

yikes i was gonna say mine made an alarming noise but it turnd out to be the "yz noise" but it does not sounds like that

[Pilfer8]

It's a '03 YZ450. ?

[chase1873]

wat does that mean

[kev8131]

Valves been adjusted lately? or ever?

[Pilfer8]

mine makes a racket too. From what I've read its normal...

[chase1873]

the valves may need to be done... but its starting first kick even when cold? so i figured they were fine. and ya i herd they make alot of noise, and i wouldnt be worried but this is a new noise i never herd before.

[tnl]

That's exactly how I described the noise on my 05 last year and found out that my kick start lever was rattling on the knuckle not the shaft/gear. I just wedged some grease in there because it wasn't loose and it hasn't made that noise since then. I'll bet you that's it!

[kain522]

My 04 makes some noise as well. Other 04s and 05s I've listened to make a similar racket, so it seems to be normal. The bike runs really strong, and even after sitting all winter it fired up after 6-7 kicks. Just the nature of the beast, I guess.

[kev8131]

Let us know what you find.

[Ga426owner]

You may want to get a 2nd opinion....I have seen several of these have some bearing problems (various) in the motor with a ton of hrs on them....how many hrs are on your bike. Yes they are loud and noisy, but when a new noise like you describe starts....I suspect a bearing issue

[08Yamee450]

Maybe your chain is loose??

[chase1873]

im goin to check the kick star and break lever and all that stuff again to make sure thats not it... i will try to get the valves looked at soon. thanks guys for the help.

[chase1873]

thats what i was afarid of, me and my dad oth think it sounds like it spun a bearing... $$$$

[tnl]

Ride it and when you hear the noise reach down and grab the kick starter lever and see if it stops.

[chase1873]

im 100% sure its the motor making the noise... i have a good buddy that works at a motorcycle shop hes taking a look at it now to see wat he can find. thanks for the help guys.

[chase1873]

hey guys... i just got word on the bike, one of the valve seals was not holding compression/leaking, and the clutch basket was rattling. thanks for the help.

[kev8131]

Glad to hear you got it figured out. Yee haw!!!