Acting like it’s out of time

Haven’t started the bike in almost two months while doing a mostly cosmetic rebuild. Only thing I did to the motor was shorten the exhaust, change the oil, checked valve clearance, and put a manual cam chain tensioner on it (MCCT from TT). Got it started up today and it had a hard time staying running without choke even after it was warm. I kept adjusting the idle thinking it was just set too low. I setup the MCCT per the instructions by rotating the motor while I had the valve cover off but I thought I heard chain noise. As I was adjusting the tensioner I'd get a quick backfire and it would die. I was afraid I went back too far and it jumped a tooth. 

So I pulled the valve cover off and rotated the motor to TDC. It looks like it's in time to me per the service manual (15 links between cam pulley marks). 

I took some pictures to post to make sure I'm looking at it right and to see if there's something else I should check. It ran good before I tore it down. 

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Line is not centered in the window and can't see the marks on the cam gears at all.  Need to remove the gasket for the cam marks to line up on the head surface.  Probably dirty carb from sitting too long

yeah, first guess is bad gas or gas in the oil ..

1 hour ago, Noble said:

Line is not centered in the window and can't see the marks on the cam gears at all.  Need to remove the gasket for the cam marks to line up on the head surface.  Probably dirty carb from sitting too long

 

The T is perfectly centered.  I didn't know about the other marks that line up with the head.  I'll pull it back off and look at that.

 

It just sounds weird too.  Like it's straining and doesn't want to rev.

51 minutes ago, Doc_Possum said:

 

The T is perfectly centered.  I didn't know about the other marks that line up with the head.  I'll pull it back off and look at that.

To get TDC you need to use the index line, not the T next to it. The T is there to notify you that the index line is used for timing. (Atleast I'm lead to believe that)

However I can confirm it needs to be the straight line which is shown to the left of the T in your picture. 

 

Here's a link to help determine if it's in TDC to help check timing, clearances etc.

 

2 minutes ago, Kor3y101 said:

To get TDC you need to use the index line, not the T next to it. The T is there to notify you that the index line is used for timing. (Atleast I'm lead to believe that)

However I can confirm it needs to be the straight line which is shown to the left of the T in your picture. 

 

Here's a link to help determine if it's in TDC to help check timing, clearances etc.

 

 

OHHHH.  I see the line now.  Dang, it might be way out time.

Not sure if this is relevant but, I installed an automatic chain tensioner once in my KTM 250xcfw and it didn’t open which caused the chain to be slack and jump a tooth. 

Not sure if it’s the same type of tensioner but it wasn’t fun. I went back to Stock and NEVER had a problem!!

 

 

OHHHH.  I see the line now.  Dang, it might be way out time.

There is a lot of circumference to that flywheel. That little difference isn't going to move the cams much at all. They are likely spot on. You probably should drain the fuel and replace the pilot jet.

 

26 minutes ago, ohiodrz400sm said:

There is a lot of circumference to that flywheel. That little difference isn't going to move the cams much at all. They are likely spot on. You probably should drain the fuel and replace the pilot jet.

 

Thanks.  I haven't had a chance to dig into it and re-check the timing but the fuel is brand new.  Carb was supposedly rebuilt by a shop over the summer, but a nut fell off the throttle linkage bolt the other day so I'm not so sure about how good of a job they really did.  

The cam chain looks like there's no tension on it  (actually, looks like there's slack in the chain) between the two cam sprockets.   Mine is under tension from the cam chain chain tensioner when I check valve clearances..   May adds some weight the comments from 'Highsided' above.

If it starts and will run with choke on, then its not timing. Pilot jet is plugged up from sitting. If you use gas with ethanol, that is your problem. Need to use an ethanol treatment to take care of the problem

Ok I finally had time to open it back up. I also took the bowl off the carb and cleaned it. The main jet was pretty dirty. 

So here are pictures of the timing. The exhaust side looks off to me. Intake is dead level but exhaust side is not.  But I have 15 links so I'm confused. 

Possibly a stretched chain??

 

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67C37F15-BBD8-4B3C-909F-D1FC542C8B53.jpeg.1c4d1df0afa1ed062266548940fa56c0.jpeg

 

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Edited by Doc_Possum

Looks fine.  Keep in mind "out of time" is a tooth or more and you are certainly on the right tooth.  Small differences in the timing marks are unimportant.  Yes the chain is probably a little warn.

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