YZ426 MOTOR



7 replies to this topic
  • BRIAN68

Posted September 25, 2001 - 07:38 AM

#1

I HAVE A 2000 YZ426 WITH ABOUT 30HRS ON THE MOTOR.ALL THE MAINTANCE HAS BEEN DONE BY THE BOOK.THIS WEEKEND AT THE RACES IT SEIZED ABOUT 10 MINUTES INTO THE MOTO.COOLANT,OIL LEVEL,AND EVERY OTHER VISABLE THING WAS FINE.
I HAVE NOT TORE THE MOTOR DOWN YET BUT ANY IDEA ON WHAT HAS WENT WRONG TO CAUSE THIS PROBLEM.

  • yzernie

Posted September 26, 2001 - 06:37 AM

#2

Brian,

Please let us know what you find out.

Ernie

  • BRIAN68

Posted September 26, 2001 - 09:02 PM

#3

ERNIE,
I DID FIND OUT TODAY IT WAS THE CRANK NOT THE TOP END BUT STILL DONT KNOW WHAT CAUSED THE PROBLEM

BRIAN

Originally posted by yzernie:
Brian,

Please let us know what you find out.

Ernie



  • yzernie

Posted September 26, 2001 - 01:06 PM

#4

Brian,

Sorry to hear about the crank. If there is some good to come out of this, at least we know it wasn't a flawed top end.

Ernie

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  • Boit

Posted September 26, 2001 - 06:48 PM

#5

I wonder if there was a lubrication failure? Sometimes when the oil is changed and the engine is restarted, the oil pump loses its prime and oil is not pumped past the filter. On page 2-10 of the manual for the '00 model, there is a general schematic of the oil flow. The manual recommends that the galley bolt at the rear of the head be loosened slightly when restarting after an oil change to check that oil is being pumped. These types of failures always make me suspect a lack of lubrication as the most likely suspect. That's not to say that there can't be some other cause.

  • yzernie

Posted September 26, 2001 - 08:35 PM

#6

Boit,

You bring up a valid point. I used to check mine every time I changed the oil. It got old after a while and I quit doing it. I took it for granted that everything would be ok. I think I'm gonna start doing it again.

Thanks, Ernie

------------------
Life is too short, work hard...play hard
01 YZ426, 99 YZ125 too many more to list!!

  • Scott_F

Posted September 27, 2001 - 04:32 AM

#7

Brian, be sure to upgrade to the '01 crank. It has splines for the CB gear rather than the keyway.

  • 426CANUCK

Posted September 27, 2001 - 07:24 AM

#8

Man do i got news for you guys ! Bad news though, I had the same thing and i have spoke with white brothers about this and have been told that it's and oiling problem .
I was told to let the bike warm up for awhile before riding, so the oil with flow freely - a good way to tell is just feel the frame and when the frame is warm were the oil resvoir is then you should be ok !?!
I start my bike and get dressed while it is running , then go for an low RPM run around the track before i start to ROMP on it !
Don't quote me on this , this is what I've been told . Call White Brothers and talk to there Tech guys an ask them what they think!
(By the way it will problably be the connecting rod bearing) If you have any probs just e-mail me at jhenry@ur.com





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