having a problem with my 06

[youngr24]

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.

[02YZ426]

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

[youngr24]

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

[02YZ426]

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]

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]

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]

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!

[motoclay]

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

[Coy229]

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]

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

[youngr24]

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]

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

[MJC476]

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]

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]

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.