Removing rocker arms while head is still assembled?

[ippytattoo]

I have a quick question for the more experienced out there. I have had a few of these heads apart but for the life of me I can't recall if there is any reason you can't remove the rocker arms with the head and motor assembled in the frame. Do any of you know right off the top of your head why there would be a problem with this? I have a head and rocker box at home that i will take apart tonight but thought I would throw out the question. Thanks for any input.

 

[XSLeo]

There are tubes that run up into the rocker box, these tubes block off part of the hole the rocker arm shafts go in. You have to remove these before the shafts come out. No way to remove without pulling the rocker box. This requires pulling the engine.
Leo

 

[alwaysmonday]

Leo - I am reinstalling the rocker arms into to rocker box and I know that the threaded portion of the shaft faces outward. The opposite side of each shaft has reliefs cut in it to allow the oil into the shaft and lubricate the rocker. My question is, when reinstalling the shafts, do I press them in until the relief side of the shaft bottoms out in the rocker box...or do I only press them in until I can install the sleeve and o-ring which you reference above? I don't want to press them in to far and block the oil passage feeding the shaft and I have no means of measuring the depth of the reliefs to confirm that I won't block the oil passage if the are pressed in until the shaft bottoms out in the rocker box. Thanks in advance!

Jon

 

[XSLeo]

I don't recall exactly, it was 3 or 4 years ago I had mine out. I think you have to push them all the way to get the sleeves in.
Leo

 

[ippytattoo]

I forgot about those. Thanks for reminding me Leo.

 

[retiredgentleman]

Leo - I am reinstalling the rocker arms into to rocker box and I know that the threaded portion of the shaft faces outward. The opposite side of each shaft has reliefs cut in it to allow the oil into the shaft and lubricate the rocker. My question is, when reinstalling the shafts, do I press them in until the relief side of the shaft bottoms out in the rocker box...or do I only press them in until I can install the sleeve and o-ring which you reference above? I don't want to press them in to far and block the oil passage feeding the shaft and I have no means of measuring the depth of the reliefs to confirm that I won't block the oil passage if the are pressed in until the shaft bottoms out in the rocker box. Thanks in advance!

Jon

You're worrying about nothing. Yamaha cleaverly designed the inner end of the rocker shafts, so that when they are pushed firmly inward, the relief cut-outs will allow the oil to freely flow. Just push them fully inward until they bottom out.