Loss of power after head gasket swap

[Guest]

I am not new to this forum - I had an account previously and haven't been around for a while. Here is my problem...

I have a 79 GS850 on which I just replaced the head gasket. Prior to replacing the head gasket, it was running fine. I had recently (within <2000 miles) adjusted valve shims, replaced crab O-rings and sealed the airbox.

I took it for a rip right before replacing the head gasket and it ran great. After getting it back together, it gives me a hard time starting and is way down on power. No strange noises and seems to rev ok, but just no guts, especially down low--maintaining 50mph uphill is difficult.

I replaced spark plugs and adjusted ignition timing - no help. The plugs look like it might be running a little lean but not too bad.

What could I have screwed up? Fairly certain all the shims went back in the right places... could I have screwed up cam chain timing? Or maybe just needs to be re-shimmed? I didn't recheck clearances because I assumed they were fine having been done so recently.

OR could it be an air/fuel problem?

I really don't want to take off valve cover again but guessing that's in my future...

[tkent02]

Cam timing is the most likely.

[brendangs850]

Cam timing is the most likely.

Yup. Just pulled the cover off and that is definitely what is happening... way off. No idea how I managed to do that.

Is there an easy (easier) way to fix this, without taking cams all the way back out?

I thought I could remove the tensioner and move chain but I can't seem to get enough slack in chain to get it off the sprockets.

[Flyboy]

Just have to remove one cam to get enough slack.
Remove the intake cam, position the exhaust cam correctly and reinstall the intake cam as required to line the marks up.

[brendangs850]

Before I button things up again, would appreciate if you guys could please give me a second set of eyes on this... do these pictures look right? They are taken at same time. I am not sure if arrow should be pointing more directly at head or if parallel is what you are looking for.

I am not sure how I screwed up the first time and really don't want to take this apart again.

[brendangs850]

Well, just for the record - cam timing must have been it. No idea how I messed it up to begin with, but after triple checking everything I got it back together and she runs great!

Thanks for the help.

[Big T]

Don't worry, it happens to the best of us

Glad you found the problem