engine chirping sound at low rpms WTF??

[6fiddy]

I noticed that my 426 makes a chirping sound here recently at low engine speed, just over idle, then goes away at higher rpms, and comes back at the same rpm when shifing thru the gears. Sounds like that styro-foam against styro-foam type sound. Performance is still good. No diff in the power, just a peculiar sound. Anyone been there,done that???

[MathProf]

It is hard to compare sounds, but check your rear wheel alignment and chain tension.

Sometimes a loose chain will make strange sounds especailly if it's wet while you are riding.

Start with something simple.

[Math]

Not sure to know what "chirping" means (sorry for my poor English) but I assume you may be hearing your chain hitting the chain guard close to the front sprocket. I have a 16t up front and it occurs when my chain has too much slack that I hear strange noises.

Another thing is that you might be hearing your timing chain.... the one that drives the head cams. If it is the case, hearing that sound is pretty normal at very low rpm... if you want to feel better, you can take your cam cover and chain tensioner off and inspect the chain for wear, proper tension... you could check your valves at the same time while you are in there...(even if the noise you hear probably has nothing to do with valves).

[6fiddy]

Not sure to know what "chirping" means (sorry for my poor English) but I assume you may be hearing your chain hitting the chain guard close to the front sprocket. I have a 16t up front and it occurs when my chain has too much slack that I hear strange noises.

Another thing is that you might be hearing your timing chain.... the one that drives the head cams. If it is the case, hearing that sound is pretty normal at very low rpm... if you want to feel better, you can take your cam cover and chain tensioner off and inspect the chain for wear, proper tension... you could check your valves at the same time while you are in there...(even if the noise you hear probably has nothing to do with valves).

Thanks for the info I will check it out tonight...

[Math]

Tell me again... do you hear that sound as you try to accelerate from low rpm (when you twist the throttle from low rpm)? Or is it a constant noise at low rpm.

If it's the former, your chain or timing chain is likely generating the sound you hear. If it's the later, I don't know.

[byggd]

I noticed that my 426 makes a chirping sound here recently at low engine speed, just over idle, then goes away at higher rpms, and comes back at the same rpm when shifing thru the gears. Sounds like that styro-foam against styro-foam type sound. Performance is still good. No diff in the power, just a peculiar sound. Anyone been there,done that???

Did you recently remove the airbox lid on your 426? Mine started making a chirping sound as soon as I did and it turns out it was coming from the carb Mine made the chain slap noise at low RPM until I did the free mod but I wouldn't describe it as a chirping noise.....sounded more like the engine was pinging.

[gmoss357]

brake drag

[6fiddy]

Did you recently remove the airbox lid on your 426? Mine started making a chirping sound as soon as I did and it turns out it was coming from the carb Mine made the chain slap noise at low RPM until I did the free mod but I wouldn't describe it as a chirping noise.....sounded more like the engine was pinging.

Nope. My air box has been modded for a while..but thanks for your input

[Matty05]

I get that when I go very slow in a high gear.

I think it is the torque playing with the chain.

[Derik Tate]

my bike also has that sound when climbing hills at low rpm. It reminds me of turbo sound my truck makes. Anyway, nothing has failed on it in 3 years so i don't stress on it. Sorry I'm not technical with my reply.

[tp3dxf]

How about suspension linkages that need grease? My noise turned out to be suspension related. Shock spring was rubbing under compression and I could only hear it at low speeds. It rubbed at higher speeds but I just couldn't hear it. I finally found the sound after a close inspection of my suspension. A few coils on my rear suspension were worn almost to the metal. If I remember correctly they were sliding against my inner Big Gun exhaust system.

[25year2stroker]

I had to check again tonight and it appears I have the same chic-a-dee coppin a free ride(little bastard) 05 wr450 225mi free mods,ais/turbo properly disposed of,jd kit,zip screw,air box knock outs & breather mod. No complaints in the performance dept.Although I think my arms are a inch longer since the mods? From just above idle + a few hundred rpm's I get a couple of tweet-tweets and then it's gone. Buster brown hasn't delivered my tach yet so I don't know the exact rpm but it's not much above idle, no drivetrain issue's as it happens on the stand also

[adrenalinejunky81]

I think (hope) theyre supposed to be kinda loud with BS noises at low motor speeds, cause mine does it too (no chirping though). I just recently replaced the timing chain and inspected the tensioner + guides but they still make noise,...suppose its normal?

[adrenalinejunky81]

Oh yeah, if your worried pull the flywheel (I imagine your bike has one like my WR?) and make sure its not the stator grinding the inside of it. Youd be surprised how easy it is for a dumb little piece of gear tooth or something to get stuck in there, or if your bearings are going...

[RichieGoatGruff]

Not sure to know what "chirping" means (sorry for my poor English)

Chirping is the sound a bird makes....

[tshe1]

I noticed that my 426 makes a chirping sound here recently at low engine speed, just over idle, then goes away at higher rpms, and comes back at the same rpm when shifing thru the gears. Sounds like that styro-foam against styro-foam type sound. Performance is still good. No diff in the power, just a peculiar sound. Anyone been there,done that???

try to determin from where the sound comes: is it from the head direction,bottom,or gear.

can you hear the sound when the bike stand on neutral?

i think that the sounds that you hear comes fromthe bearings (maybee on the cams), when RPM goes up it increase the oil pump delivery and the bearings get more lubricating (floating on the oil) thou the sound goes away.

check oil capacity (maybee it's time to replace it).

hope i helps...

[new2blu]

My 03 450 makes the same noise; I not sure but I think it is high velocity air passing under the carb slide. Mine kind sounds like a vacuum leak but none have been found. It kinda sounds like a "chirping whistle" to me.

[Rich_in_Orlando]

I know the exact sound you are talking about. That's what my bike sounds like- styrofoam on styrofoam. Don't worry about it- it's normal. I think those of us with quieter exhausts hear more engine sounds than those with louder pipes and that's just what these motors sound like.

[ncmountainman]

i've given up trying to interpret the sounds of a yamaha 450,because if you listen too hard it'll worry you to death i compare its sound to a yanmar single(diesel) i had once

[jmurray289]

Another post suggests its the carb slide. I started mine with the sat off yesterday and got concerned with a low RPM rattle... appeared to be coming from the airbox... but it appears that the FCR carb is a noisy little devil.