1986 Honda 250sx cam chain timing/tensioning question

[Heavymand]

Hey guys, I'm new here and I have a question for you. I put a new head on my 1986 Honda 250sx and timed the cam chain according to the manual. With the T lined up with it's mark and the two notches lined up for the cam sprocket and all that good stuff per the service manual. When I put my chain tensioner back in next it moved my cam sprocket timing marks off just a bit. Looks like maybe a tooth worth off but the manual doesn't mention that happening. I put the valve cover back on and adjusted the valves and I can feel it suck on the intake stroke when I turn it with a ratchet. My question is the timing marks. Is that normal for them to be off after the tensioner is installed or did I do something wrong. I went by the manual but just want to be sure. Thanks for any help

[shortline10]

Your timing chain is probably worn out / stretched . Also always time the cam with a little pressure on the guide , can use your finger threw the tensioner hole . This will insure the timing is correct with tension .

[Heavymand]

I bought the machine disassembled so before I get too far into putting it back together I should probably revisit the timing.

[ATC200X4716]

The tensioner only takes slack out on one side, so as the chain stretches the cam timing moves. If you are unsure consider backing it up 1 tooth to see what it looks like to convince yourself where you had it was right. A stretched chain won't line up perfect, but make sure to push on the guide to take slack out like was said above.

[Heavymand]

Ok so I'm assuming that the manual is written as if I wasn't using a worn/stretched chain and the issue I have wouldn't be an issue if I was using a new chain. So when I timed it without tension on the chain, when I installed the tensioner next with my worn/stretched chain I essentially put it a bit out of time? That actually makes sense because it never crossed my mind that my chain would be worn/stretched. Am I understanding you guys correctly?

[shortline10]

Not that the manual if off , even if the chain was new you have to put a little pressure on the guide to insure the slack is out to set the timing correctly , having a stretched chain just makes it a little harder to get lined up exactly , which it might not .



Ok so I'm assuming that the manual is written as if I wasn't using a worn/stretched chain and the issue I have wouldn't be an issue if I was using a new chain. So when I timed it without tension on the chain, when I installed the tensioner next with my worn/stretched chain I essentially put it a bit out of time? That actually makes sense because it never crossed my mind that my chain would be worn/stretched. Am I understanding you guys correctly?

[Heavymand]

Oh... OK I'm pickin up what you're puttin down. Any way I look at it I need to re-time it with a little tension on the chain to get it as close as possible.