2008 yz 450 will not start

hello anyone out there? Need help! I had a stuck exhaust valve on my bike. I repaired the valve and set all the valves to spec. I did make sure cams were tdc. After putting bike together i tried starting it with no luck. I didnt check the spark yet because i have to buy a special plug wrench for this bike. Has any body had issue with the 08. Let me know what you think. I had increased my pilot jet when i bought bike due to backfiring. I believe it is a 50. Any help would be appreciated. Thanks Steve

okay. I checked the plug and do have spark. since i was in there i put a new one in. Tried to start again no luck ,a million kicks. Took apart and checked carb. Pulled all jets out and cleaned. They all looked clear blew them out anyway. Put all back. Tried to start. no go. I pulled valve cover off and check cam position and still at tdc marks on ex and in at side of head like manual says. I am at a loss. very frustrating being that bike is relatively new. Any suggestions at this point. Thanks :thumbsup:

Timing is my guess. Ping Grayracer513 in this forum. He's the guru of all things Yamaha.

dumb question probably...have you tried turning the idle up? Does it sound like it wants to start?

thanks moto x. i am sure my timing is okay. I used the last line. theres the H and then the I on the stator. I used the I maybe that is the problem and i should be in between the two not sure..

yea i tried that. I forgot to mention I live in Jersey and the temps are around 35 to 40 degrees

occasionally i hear a pop but doesnt sound like it wants to start.

did you mess with the carb slide at all? The plate that attaches to it is real easy to install upside down...

also maybe a fresh spark plug

I did my valves 2 weeks ago. Did everything just like the manual said. My bike would not start....... Long story short the manual is wrong. In the picture it shows 7 full links in-between the two cams. There is only supose to be 6 & 1/2. After I made the change it started right up.

I did my valves 2 weeks ago. Did everything just like the manual said. My bike would not start....... Long story short the manual is wrong. In the picture it shows 7 full links in-between the two cams. There is only supose to be 6 & 1/2. After I made the change it started right up.

correct 13 pins, http://www.thumpertalk.com/forum/showthread.php?p=7467845#post7467845

no i didnt touch the slide just cleaned the jets

yea your prob. right. I counted the pins in between the marks at 12 oclock and came up with 12. I think it should be 13 which is prob. the links you counted. What has me puzzled is that i have the dots at 12 and dots at each side of head. That count is still 12..

thanks for your help. I go by the 9 and 3 oclock marks and they are on with the head. At this point i counted 12 pins between 12 oclock. I dont know.

My cam marks are at 3 and 9 oclock. The pictures in book definately are not to go by. Your marks were the same right.

yea i tried that. I forgot to mention I live in Jersey and the temps are around 35 to 40 degrees
This is probably the problem. Put a fresh plug in it, and try giving the bike 3 to 4 good twists on the throttle before kicking it with the choke on. If it doesn't start in two, give it another twist and try again.

Yea thanks. I put a new plug in yesterday and tried the throttle routine. Every once in a while I get a pop and that's it. I even have fresh gas in there. Four strokes should start up fast this is crazy. I will keep trying later today. Thanks

Sometimes in winter when it is very cold I put a little space heater blowing on my bike for 15-20 min. then start it.

thanks for your help. I go by the 9 and 3 oclock marks and they are on with the head. At this point i counted 12 pins between 12 oclock. I dont know.

Then your cams are not in correct relation to each other. There should be 13 pins between the 12:00 index marks on the cams. Realign then so that you have 13 pins between the marks AND so that the timing marks are on level with the head at TDC.

in order for me to get 13 pins my cams will not be at 12 oclock on the marks and the 9 and 3 oclock marks will not be there. everything is dead on unless they have to be off the 12 oclock mark.. i dunno. i may try the space heater thing.

in order for me to get 13 pins my cams will not be at 12 oclock on the marks and the 9 and 3 oclock marks will not be there. everything is dead on unless they have to be off the 12 oclock mark.. i dunno. i may try the space heater thing.

The index marks do not necessarily have to be exactly at 12:00, just use them as a reference to be sure that the cams are in correct realtion to each other (13 pins). The important step is to make sure that the timing marks are are as close to being level with the head at TDC as possible with the 13 pin gap between the index marks,

If you have 12 pins between the index marks it is wrong.

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