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Discussion Starter #1
I'm so very close to completing the rebuild of this engine! I was hoping to finish today but I've thrown in the towel because I can't get the tach side cam bearing to slide into place. As soon as it touches the cam, it stops. It's like the two parts don't go with one another. Any advice? Common things people screw up on these? Thanks!
 

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You may want to consider taking the sprocket off the cam and installing the cam bearings and then putting the sprocket on.
What steps are you following for assembly?
You using assembly lube? I can't tell from the photos but everything looks dry?
 

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Discussion Starter #3
Ok, next time I'm out there I will give it a go with the sprocket off. That seems like a reasonable fix. I assume the logic is that the chain is putting enough downward pressure on the cam that it isn't hitting the bearing at the proper angle?

My assembly guide has primarily been Saturdays Wrench, I've watched the episode where they assemble the top end about 200 times and taken copious notes.

Yes, everything is coated in assembly lube.
 

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Sensei
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No need to remove the sprocket........
Proper steps to follow......
 

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Sensei
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#1 Position cam to put all four lobes down-ish which is approximately 90 degrees past the LT index (and where it should have been when installing the rockers)
#2 It's easier for me to put the tach drive side on first, noting that you MAY have to rotate the driven shaft (I use the cable inner or needle nose pliers) as/to cause the drive gears to mesh...
#3 install the point-base (left) side head cover (you can use light finger lift or pressure on the "spout" to hold it level and centered)
#4 then install the cam chain tensioner......

Phone if necessary....540-525-5199
 

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Discussion Starter #6
Thanks Steve. A couple of questions:

1) Why does the cam lobe positioning matter? If you say it does I believe you, I'm just curious as to how it affects things. Downward pressure from the rockers?

2) How much force should this require? In Saturdays Wrench, the guy uses a rubber mallet or dead blow hammer to tap it home. This seems like a bad idea when dealing with 2 machined surfaces, but he's a professional motorcycle mechanic and I'm...not.
 

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I always put a couple nuts on the studs to compress the 3 parts together and give a little bit more slack to the chain. I use two in the center, diagonal from each other, couple large nuts as spacers then a washer and a nut. Pull it down gently.

Having had to pull the tach side once I was able to get the speedo gears to mesh by twisting the cover back and forth while pushing it in.

I follow Steve's steps.

If you don't move the cam to the suggested position then as you fit the cover you are trying to compress a valve.
 

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Sensei
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#1 Yes, this positions the lobes so the rockers are NOT transferring any valve spring pressure to the camshaft.......
#2 He's forcing the gears to mesh.....hand pressure is ALL it should require.....Please try it following my suggestion, or phone....
 

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Discussion Starter #9
Boomer, the Saturdays Wrench mechanic had nuts on the way you described. He never explained them so I didn't think much of it. Makes sense.

Steve, thanks again. I'm done for the evening. With any luck I can get out there tomorrow after work and follow your steps. I will report back.
 

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Discussion Starter #12
Mission accomplished! With a couple nuts on the studs, cam lobes down, and rocker arms loose, I got it together! I went ahead and pulled the ignition side off and started fresh. Thank you all for your replies and tips. I'm one step closer to having a running engine.
 
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