00 YZ426F Engine Noise!


44 replies to this topic
  • Ga426owner

Posted August 16, 2005 - 05:46 AM

#41

my guess would be a bearing issue - cam bearing or other bearing. My friends 00 426 got louder and louder - did not seem to stop performance - just got louder and louder.....

  • BergArabia

Posted September 29, 2005 - 03:35 AM

#42

I "discovered" the same thing...I had never started my WR426 without my helmet on (yes, it's true! Gotta set the example for the little guy to NEVER ride without a helmet...), and when I put hotcams in a month ago I started it in the garage to break in the cams. I shut it down right away thinking that maybe the cam chain tensioner wasn't extended all the way. It was. The guides all looked fine. The sprockets were new. The oil has always been clean. I put it back together and started it again. Still the same. Lots of rubbing, clicking and clacking...machine noises. I called the wife out to the garage, and she laughed her ass off. Said that it's always sounded like that, and so do all my friends YZs and WRs. So, I called my buds, held up the phone, and thay confirmed. Yup, our bikes sound like that too. Have since new.

Keep an eye on the oil filter, change oil often, and enjoy.


Pheww that makes me feel better. I have just come running up from the garage underneath our apartment building.. Like you I have always had the helment on and my YZ 450 is almost brand new so I was very disappointed to hear all that slapping, thumping and whacking coming from the engine. I thought I was paying for being a cheapster and putting in 20 50 oil so I changed that to Mobile 1. Still the noise... Bike runs great pipe glows red too...

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • azdragoon

Posted September 29, 2005 - 09:53 AM

#43

Does it sound like a rolling and grinding sound? I've had bikes with main bearings shot sound like this. Get a stethescope and hold it to the lower end. You should be able to tell what the noises are. If in doubt take it to Yamaha and ask that a mechanic listen to it, they shouldn't charge you anything. I just bought an 99, it has a aluminum skid plate, and no noises whatsoever.

  • darksun27

Posted September 29, 2005 - 10:09 PM

#44

i think i might know what it might be. i am going throught troubled times rite now with my 426. so far i have broke 2 shift forks in a row (taking it to yamaha dealer to inspect wear tomorrow) and the last time i put it back together it was making that knocking noise. i just put it in the back of my mind and rode on. after my 2nd shift fork broke (3days ago) i tore it back apart. not because of the noise but because of my fork breaking. and when i got to the top end i saw that the valves were hitting the cylinder slightly. this is certinly what was causing the knocking noise from my motor. might be what it is on yours to. make shure your timing is right. take the gas tank off and the valve covers. its a tight fit getting the cover out of there but it will fit (you dont have to remove the whole motor) lign up the mark on the flywheel and make shure your timing is right with the cams. if its not that it your valves might need to be adjusted

  • probikerguy2

Posted October 05, 2005 - 04:22 PM

#45

I bought a used 00 426 and it came with a horrible knocking almost clanking noise when u ran it. 426's were notorious for wearing down the keys that go between the gears and the counterbalance so i took apart the engine and just as i suspected i took out one of the keys (i think it might have been the counter balance one) and was soo worn out it was rounded causing it too have tons of access play and causing it to knock..put a new one in and has never been quiter since.





Related Content

Wiki
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info


Articles
  • 0 replies
Forums
Photo

Michigan Motocross Tires by 288yz450


Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply
Reviews

Yamaha YZ450F 2017 by Chris.GVS


Yamaha YZ450F 2017
  • - - - - -
  • 0 reviews
Forums
Photo

Snake pit oct 30th by The Anvil


Dirt Bike   Dirt Bike Regional Discussion   California
  • Hot  293 replies
Forums
Photo

Is it worth it? (Cam and High compression piston) by macgi77


Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies
 
x

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.