07 YZ450 Engine Noise?

[mxmaddman]

My exhaust chirps. My bike makes yamachatter noise. Sounds normal now since im used to it. Its funny if i don't ride it for a while when i start it I question it too. The 08s are the ticket from what reviews say. We will see what longevity they have by this time next year.

[JRYZ426]

Stupid question, I have a newly aquired 02 YZ426 and from what you guys are saying about your 450's engine noise is making me feel better about what I am hearing from mine. Back to the question... Does the 426 motor have the same noise issues as the 450's? Mine sounds like a cross between cam chain noise with a little detonation/piston slap added in. The higher the rpm the quieter it gets. I do have a carbon fiber skid plate which may be redirecting he noise upward...

Thanks,

JR

[mxmaddman]

Stupid question, I have a newly aquired 02 YZ426 and from what you guys are saying about your 450's engine noise is making me feel better about what I am hearing from mine. Back to the question... Does the 426 motor have the same noise issues as the 450's? Mine sounds like a cross between cam chain noise with a little detonation/piston slap added in. The higher the rpm the quieter it gets. I do have a carbon fiber skid plate which may be redirecting he noise upward...

Thanks,

JR

Has it been rebuilt? If not you might be looking at a full overhaul. Chatter is normal ticking and knocking is not. The 426 motors chatter too just like the 450 and 250's do. what gas octane are you running?

[JRYZ426]

Has it been rebuilt? If not you might be looking at a full overhaul. Chatter is normal ticking and knocking is not. The 426 motors chatter too just like the 450 and 250's do. what gas octane are you running?

The bike has maybe 30-40 hours on it. I run 91 octane which is the highest octane you can get in Arizona with out running race gas. I have put about 4-5 hours on it since I bought it a few weeks ago. The bike starts and runs very well...

[grayracer513]

Yes, the 426 has the same noise issues as the 450, and the skid plate will amplify it.

Some of the noise is backlash in the primary gears, balancer shaft, and the trans. Some is piston noise (not much) and some is just the valve train rattling around. It goes away at higher speeds because the engine then runs at a more steady rpm. At speeds near idle, it is actually accelerating with each power stroke, and decelerating with each compression stroke.

[albertaguy]

HA you wont ever need to rebuild a yamaha thumper

Except when you suck sand up your breather hose; true story.

[jughead182]

i now have an 08 very very quiet

i had noise in my 07 but stupid me iforgot to drain oil throught both drain bungs , after a complete oil change everything ok ,

stripped the motor everthing in tip top shape bullet proof

riding yamaha since 1995 love them

[JRYZ426]

Yes, the 426 has the same noise issues as the 450, and the skid plate will amplify it.

Some of the noise is backlash in the primary gears, balancer shaft, and the trans. Some is piston noise (not much) and some is just the valve train rattling around. It goes away at higher speeds because the engine then runs at a more steady rpm. At speeds near idle, it is actually accelerating with each power stroke, and decelerating with each compression stroke.

Thank you sir! I feel better now.

[yzfjbw323]

i now have an 08 very very quiet

i had noise in my 07 but stupid me iforgot to drain oil throught both drain bungs , after a complete oil change everything ok ,

stripped the motor everthing in tip top shape bullet proof

riding yamaha since 1995 love them

Ahh, Am I doing something wrong whats a drain bung?

I am already nervous about owning a four stroke what is a bung??

[grayracer513]

"Bung" is a British term for a drain plug. No worries.

[Big Black]

i just rode my 08 yz450 for the first time on saturday and it makes some engine noises, seems to be as your letting the clutch out and at low rpms, it started doing it after about 3 hours of riding it, is this also normal?.............it also popps and backfires like crazy on decel and while riding along at a slow steady pace, it really sounds like shit, tried adjusting fuel screw but it didnt really help

[albertaguy]

Mine seemed to get better when I put on quickshot 2 accel pump cover. Everyone here will tell you it's normal, maybe it is, I sure hated when it did it. Neither my 05 crf or my 08 ktm do it so not sure why the yzf 450's ALL seem to. That being said it ran fine when you were on the gas.

[mxmaddman]

i just rode my 08 yz450 for the first time on saturday and it makes some engine noises, seems to be as your letting the clutch out and at low rpms, it started doing it after about 3 hours of riding it, is this also normal?.............it also popps and backfires like crazy on decel and while riding along at a slow steady pace, it really sounds like shit, tried adjusting fuel screw but it didnt really help

If its popping on decel its too lean.. jet the pilot a tad richer and it wont do it anymore. The clutch engagement noises are somthing that all bikes do. Once the engine starts to come underload they make the noise. Not all yzf's pop, its not normal.

[nap__kxf]

No kidding. I was thinking loose chain, loose parts etc. I even changed the oil a couple times checking for metal shavings. How do you have you bike setup?

yeah, i get the same thing on my 07, its actually how i ruined my dipstick. we were out on trail and starting on our way back and about 15 miles from the truck i heard that and i thought maybe i forgot to tighten one of the oil drain bolts since i changed my oil before that weekend so i stopped and i brushed off all of the dirt i saw around my dipstick, well there was piece that fell in and got stuck in the threads, and when i put my dipstick back in it stripped the threads. ?

atleast my bike shop found one last billet dipstick in idaho ?

[albertaguy]

atleast my bike shop found one last billet dipstick in idaho ?

Idaho has lots of dipsticks ? Just Kidding, I love the St. Anthony dunes

[WB450]

Idaho has lots of dipsticks Just Kidding, I love the St. Anthony dunes

?

[conv3rt]

Thanks for the reassurance. Now I know to ignore the 'bucket-of-old-nails-in-my-motor' noise. Coming from a WR250F to a YZ450F, I was concerned.

[milomilo]

yes yz450f's make a ton of noise. scary noise but i think its just them. my 02 r1 makes alot of noise 2 and i know thats normal. my friends have crf450 and rmz450 and both less noise than the yzf.

[albertaguy]

my ktm sounds very smooth compared to the old yzf.

[sandrappy]

I'm new to the 450 motors as well. I've been riding and building atv engines for years and years. I swore my 06 450 i bought this january was on the verge of blowing up from all the rattles and knocking noises it was making. I tore it apart to rebuild it and everything looked like new still. Since it was apart i obviously couldn't put it back together stock, so i ported the head, did a valve job, bored the cylinder to a cp piston, balanced the crank etc... to tighten everything up.

I got the engine running on sunday and the damn thing still sounds like it has piston slap and is knocking. I guess i learned the hard way these motors are noisy no matter what! My quesiton is if it sounds like it is knocking when everything is fine, how do you know it is about to blow up? Does it get quite???