Did my bike jump time?

I had a hard time starting my yzf the other day so I decided to check the valves. I bought it two months ago and have ridden it maybe 15 hours. In that time I have changed the oil twice but anyway, when I took the cover off, the cam lobes didnt match up. This is what it looks like at TDC(I have an E-line stator that dosent have the plugs to remove so my only way of finding tdc id to rotate with the kickstarter till the lobes face away from each other).

http://s660.photobucket.com/albums/uu322/Rockstar14125/?action=view&current=Cam1.jpg

http://s660.photobucket.com/albums/uu322/Rockstar14125/?action=view&current=Cam2.jpg

Can't tell from that side. The timing marks are on the sprockets. Show us what it looks like from the other side with the crank at TDC.

I have an E-line stator that dosent have the plugs to remove so my only way of finding tdc id to rotate with the kickstarter till the lobes face away from each other

drop a screwdriver into the spark plug hole and find the spot where its at its highest point to confirm TDC, then look at the cam gears to see if the timing marks are lined up appropriately.

Grayracer will be able to say for sure, but I don't think those pics are at TDC on the firing stroke. A properly timed cam should have those little divots at 3 o'clock on the intake (just above the head) and 9 o'clock on the exhaust, at TDC on the firing stroke (all valves will be closed).

I have heard of cam chains jumping, but not to the extent that those photos show.

yeah those punch marks should be at 9 and 3 at TDC, each cam gear looks equally off (advanced) by about 2 teeth, makes me wonder whether you're not really at TDC. Make 100% sure its at TDC, the screwdriver should be going up, then stop briefly and hit a flat spot at TDC then start going down again, you want it right in the middle of the flat spot. If you're pushing it around with the kickstart it may be hard to get it right, try getting close to just before TDC and then turn the cam gears by hand, you may be able to get enough force to move it alittle into the right position-I've never tried that, but maybe it will work. I've never seen one jump both gears, its usually off by 1 tooth on either side? If it really did jump that far off, maybe the cam chain tensioner is malfunctioning, pull it off and check it.

Ok, it must not have been. :thumbsup: Thats what I get for trying to go too fast. I will give it another try tomorrow or wednesday and see if I can get it right. :usa: Thanks for everybodys help so far. This is my first time going into the motor of anything so this is all new to me but I wanna learn how to do everything I can to it.

ok. when I say those divots I realized what you were talking about. I bought a set of feeler gauges but they dont go small enough for the intake. oh well live and learn I guess thanks everybody

Post a picture of your water pump for me, please. I'm curious about something.

ok, will do gray. I will have to do that tomorrow though. I shut everything down as it is 11:30 here and I have to get up at 6:30. also, I dont know if you read my pm about my kickstarter or read my post but does anyone have any ideas? Im trying to take this thing from duct tape, spray paint, and zip tyes to something respectable.

This is the problem with the kickstarter

http://www.thumpertalk.com/forum/showthread.php?t=760307

Timing looks right.

On the gears maybe - but judging from those previous pics (his first ones posted) the gears may have slipped on the cams.....rockstar - can you post pics of the other side of your head so we can see the cam lobe orientation at your TDC setting - somehow, I'm leaning towards that scenario....

On the gears maybe - but judging from those previous pics (his first ones posted) the gears may have slipped on the cams.....

Considering those pictures were taken when the cams were both rotated too far forward, the lobes look like they are correctly oriented to the sprockets. I wouldn't worry about it.

Hey rockstar,

I wasn't going to say anything, but if your going to start taking parts off that motor you should make sure it's clean first. If any of that dirt gets into the gears etc. your going to have a heck of a lot more problems than you started with. I enjoy poking around and learning about my bike as well. Good luck, I hope your issue is solved easily.:thumbsup:

Oh, and while you have the cover off, check your water pump impeller shaft, seals and bearing. They might be worth changing while your in there.

Hey whats up guys? ive been reading alot on these bikes because im picking up a 02 yz426 this sat and im kinda nevouse, reading these post and threads it seems these bike are high matainance. Now is this true? should i get into this?

I went and checked the original ?TDC? pics - you're right, Grayracer - too far forwards - you just don't miss a beat!

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