Are my pushrods on OK?

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Some one mentioned 4 rubber bands. I put the head on with the tappet adjusters fully backed off, with torch and implement seat the rocker to pushrod in turn and then use a rubber band as a spring substitute to hold rocker into pushrod. Do all four, torque up the head (plenty of give in the valve gear of the rubber kind) then adjust tappers one at a time.
 
Some one mentioned 4 rubber bands. I put the head on with the tappet adjusters fully backed off, with torch and implement seat the rocker to pushrod in turn and then use a rubber band as a spring substitute to hold rocker into pushrod. Do all four, torque up the head (plenty of give in the valve gear of the rubber kind) then adjust tappers one at a time.
This is what I did but with 2 bands to keep all the rocker ends in position to fit the pushrod tops.
 
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My pushrods are dicks. Tried the elastic trick, tried the dab off grease on the tips and they just won't stay in place as I out the top back on. Gonna take a few mins to relax cause I'm about to throw it across the room. Lol
 
Unless you've got 3 arms, it's very difficult to fit the head and pushrods by the book method, leading to a high risk of making mistakes.
I found it's much easier to suspend the head (with pushrods held into it by a rag) by an elastic cord over the frame top tube.
Remove the rag once the head is suspended.
That leaves both hands free to get the pushrods into proper position without worrying about losing your grip on the head.
As each pushrod is positioned in sequence, the head can be incrementally pushed downwards until the bolts can be started. Too easy.
You can even take a coffee break in the middle of the job if you want to.
I made a couple of pins to screw into rocker oil feed holes.
The elastic cord serves another purpose:- it also holds the back end of my petrol tank down.
Are my pushrods on OK?
Are my pushrods on OK?
 
My pushrods are dicks. Tried the elastic trick, tried the dab off grease on the tips and they just won't stay in place as I out the top back on. Gonna take a few mins to relax cause I'm about to throw it across the room. Lol

Are you pulling the head down using only the #1 bolt* as then you can concentrate on keeping the pushrods in position (with a hooked piece of wire, elastic bands, etc.)?

*(manual section C9,7)
 
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If ya ever get the rockers out in hand, grind the very extreme ends down close to the ball/cup end, w/o need to grind any the rest of the surrounds, to solve push rod puzzling, success each/every time. Rod slips right back in position if slips all the way down on head fumble. Rubber bands are handy 3rd hand till head clamped down.
 
I use the rubber bands between the exhaust/intake to keep tension on the ball and socket of the rocker and pushrod tops. Make sure the tappet adjusters are all the way up. I place all 4 pushrods into the tunnels of the barrel, get them seated, turn the engine over until all 4 p/rods are as even height as you can make them, then offer the head on and use a rear engine head nut from the 3 studs coming down from the head between the head and barrels as a spacer. this is to temporarily keep the head slightly raised so you can now manipulate the pushrods into their socket balls of the rockers. Use a good flashlight and with long tweezers or needle nose pliers guide the pushrods to their homes. Once the 4 pushrods are in place the tension of the rubber band should keep them there. Carefully remove the nut used as a spacer. Bring the center bolt down with care and carefully look again at the pushrod/rockers. Once you are sure they stayed put then tighten up the other nut and bolt head hardware. Once this is done bring it to tdc and one cylinder will have their rockers loose so you should be able to rattle them and the other will be on tension with the valve springs either opening or closing. torque everything down to spec and do a tappet adjustment on the loose side then turn engine over one rev and do other. Its all in the manual. If you have to do the head install in the bike then the pushrods need to be in the head as you offer the head over the barrels into the tunnel. Best to have a buddy to use as the third hand.;)
Cheers,
Thomas
 
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LAB, that is a great drawing of a cutaway Commando motor. Where did you find that?
 
André, everyone stuggled with the push rods the first time or two or three. Good to hear of your success. Perserverance precedes success.
 
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André, everyone stuggled with the push rods the first time or two or three. Good to hear of your success. Perserverance precedes success.

Thank you. Now I know. Until the next challenge. Hey, if it were easy everyone would do it. Lol.
 
I have always done my heads by the book just putting the PRs inbeween my fingers in the head then letting them drop down on the lifters with the head sitting on top of the cylinders raised I sit the rods on the rocker arms with a slim screw driver making sure each one is sitting right then slowly using number one bolt slowly tightening it in while keeping a eye on the rods to make sure they are still in position, has always worked this way without any problems, never used rubber bands or rages, find this way to be easy, a good bright torch helps and a good set of eyes

Ashley
 
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