having a problem with my 06


14 replies to this topic
  • youngr24

Posted November 10, 2006 - 04:28 PM

#1

change the oil today. it fired right up afterwards (one kick). loaded into the truck and took it to a friends. I started it at his house and rode it about thirty feet and it died. I can kick it over but its very difficault. It feels like it is not decompressing. I took the spark plug out and ran the kick starter. No problem there it turns over fine but when I put the plug back in it does the same thing. I can put presure on the kick starter and it will fall though slowly but not fast enough to start.
HELP tring to ride tomarrow.:cheers:

  • 02YZ426

Posted November 10, 2006 - 06:15 PM

#2

Sounds like the decompression pin in the cam might be stuck? Maybe take the valve cover off and have a look.

  • youngr24

Posted November 10, 2006 - 06:25 PM

#3

where will i be looking and what does it look like. I have the cover off now

  • 02YZ426

Posted November 10, 2006 - 06:50 PM

#4

There is a little arm with a spring on the cam sprocket. When the engine is running that arm moves out with centrufugal force and draws the pin into the cam. If you rotate the motor over you should be able to see the pin in the cam. The pin should be sticking out of the cam just a little so it pushes the exhaust valve open.

  • youngr24

Posted November 10, 2006 - 09:12 PM

#5

So, check this out. I pulled this thing apart and start to look at the decomprestion pin and the arm on the cam sproket. everything looks fine and operates smoothly. So I start to take everything to TDC. I can't get there. This thing jumped timing. I moved three foward on the exhaust cam and one tooth foward on the intake cam. Would a stall of the bike while it is still cold cause this bike to jump timing or do I have something else wrong.

  • 02YZ426

Posted November 11, 2006 - 07:56 AM

#6

Wow... thats the first 06 I've heard jumping teeth on the cam chain. I would usually say replace the chain, but its so new I cant see how it would be stretched yet. Maybe check the tensioner? If thats the problem, give the old one to grayracer lol.

  • TapptOut

Posted November 11, 2006 - 09:04 AM

#7

Wow... thats the first 06 I've heard jumping teeth on the cam chain. I would usually say replace the chain, but its so new I cant see how it would be stretched yet. Maybe check the tensioner? If thats the problem, give the old one to grayracer lol.


I dont know the new chains stock suck!

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

Posted November 11, 2006 - 04:43 PM

#8

Cam chains suck?? lol, i didnt know that there was even an aftermarket cam chain available. That is what you are suggesting right??

  • Coy229

Posted November 13, 2006 - 09:05 PM

#9

did you check to make sure you didnt ping a valve off the piston. you need to pull the head and make sure there is no other damage and try to find what caused it to jump. just setting it back right with out finding out what made it do it in the first place there is a pretty good chance it will do it again. if you ping a valve your gonna have to replace so expensive stuff so get it torn down now so things dont get worse

  • 02YZ426

Posted November 18, 2006 - 10:32 AM

#10

Did you get the bike running again? Just curious if you found why the chain jumped teeth?

  • youngr24

Posted November 21, 2006 - 06:11 PM

#11

I reset the timing and rode the next the day. The bike still wasn't right. I tore it down again and had a friend of my that know's 450's like the back of his had look at it. He said the same thing that the shop said (never seen one jump time before) We pull the cam chain out and it was the problem. It had stretch so much that it was binding up. I put a new cam chain in and a manual cam chain tensioner today. I will finish it up tomarrow. it should run fine (hope so, going to the desert on Friday.

  • youngr24

Posted November 21, 2006 - 06:13 PM

#12

And thanks for your help. i will let you know what the final outcome is

  • MJC476

Posted November 22, 2006 - 01:11 AM

#13

How many hours does your bike have on it? It does seem odd that a chain would stretch that much in such a short time without some sort of excessive tension or other problem

Despite what some say I would ditch the manual chain tensioner & use a stocker. The yamaha tensioners are not known to cause problems & manuls need constant adjusting. When the 065250f's were blowing up everyone jumped on the tensioner bandwagon & it turned out to be valves. Once the valves were replaced all of the tensioner "problems" disappeared.

Let us know how it goes when it fires up:thumbsup:

  • Ga426owner

Posted November 22, 2006 - 07:08 AM

#14

How many hours does your bike have on it? It does seem odd that a chain would stretch that much in such a short time without some sort of excessive tension or other problem

Despite what some say I would ditch the manual chain tensioner & use a stocker. The yamaha tensioners are not known to cause problems & manuls need constant adjusting. When the 065250f's were blowing up everyone jumped on the tensioner bandwagon & it turned out to be valves. Once the valves were replaced all of the tensioner "problems" disappeared.

Let us know how it goes when it fires up:thumbsup:


I agree - you bike has a very, very rare condition if your Chain wore out that quick...I would replace with a new oem chain.

  • youngr24

Posted November 27, 2006 - 07:21 PM

#15

Well let's put this one to bed. The bike ran great all weekend. We did two
30+ mile rides and I had no problems at all. One new cam chain and that's that. thanks for the help guys.





Related Content

Forums
Photo

Michigan Motocross Tires by 288yz450


Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply
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
Forums
Photo

First Hare scramble tips by dhend8


Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  33 replies
Forums
Photo

James Stewart back on a YZ450F by YamaLink


Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies
Forums
Photo

YZ450F 03 Sparks driving me crazy by SirAttard


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 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.