valves, rocker assemblies - 1977 R100/7

[thdomo]

I'm replacing my push rod seals and some gaskets. Want to see if I'm creating any issues. Here's what I've done.

I got the left side back together torquing in the recommended cross pattern, at 15, 25, 35, then 39 Newton meters. And then I found the rocker arm assemblies were very tight. So tight they didn't move at all.

I had set it at OT for that side but thought maybe it moved while I was working on the bike.

So I did the whole procedure to get to (OT) top dead center for the side i was working on again (valve was coming out).

After that, when I loosened the nuts the assemblies moved OK and I was able to go through the procedure of adjusting them.

First question. See any issues so far?

They were still tight but moving a little, which is, according to my research, where they should be. I then adjusted valve clearance, put the cover back on and moved to work on the right side.

I started by taking the intake rocker arm assembly off and started to loosen one nut on the exhaust rocker assembly when I remembered, I had NOT put the bike OT for the right side. Quickly put the intake rocker assembly back on but I forgot to tighten the exhaust nut. Then I moved the wheel so the crank went through one 360 degree cycle to OT,

Now I didn't look to see if the exhaust valve was coming out. I just assumed if I started at OT on the left side, and went one revolution to OT again that would put the bike at OT for the right side.

Second question, is that correct? My understanding of it is if you're at OT on one side, then go through one revolution to OT you're good for the other side. Then, if you go ANOTHER 360 your back at OT on the initial side you started at. But am I right?

Third question. Did I mess something up by taking off the rocker assembly when the right side wasn't at OT?

 

[20774]

Welcome to the forum! It would be helpful if you would include the model and year of the bike you're working on.

It's important to specify the OT in relation to the compression stroke. You mention "valves coming out". Well, yes, if you're rotating the engine and you see the intake valve begin to close, then you are approaching OT on the compression stroke for that side. Watching the exhaust valve is not part of the picture. When you see the left intake valve begin to move towards being closed, then position yourself beside the left side of the bike and slowly turn until you see OT. Now you're ready to set the valves on the left side. Don't be fooled by the statement "the pushrods could be spun". They may or may not...if the clearance is so bad, the pushrods won't spin and you'll think you're on the wrong stroke. Watch the intake valve, then look for TDC.

Once you've done the left side, you're correct you can rotate the engine until you see the next TDC mark...that SHOULD be TDC for the right side. I never really trust that but actually watch the right intake valve and then go back to the timing window to watch for TDC.

IMO I think 39 newton-meters is too much...that's 29 ft-lbs. I'd suggest that you back it down to 25 ft-lbs or 34 newton-meters. And the head bolts are torqued in a criss-cross pattern.

I probably wouldn't have set all the torque and valve clearances on the left side until I had actually gotten the right side back together. I can't remember what Oak's manual suggested but I thought he said to put one side together with light torque on the bolts, then do the other side with light torque. Then begin the process of torqueing the first side.

Don't know about taking the side apart without being at OT...I think it's just harder that way, and the head bolts are under tension a little longer, but probably was OK.

 

[thdomo]

Welcome to the forum! It would be helpful if you would include the model and year of the bike you're working on.
Watching the exhaust valve is not part of the picture. When you see the left intake valve begin to move towards being closed, then position yourself beside the left side of the bike and slowly turn until you see OT. Now you're ready to set the valves on the left side. Don't be fooled by the statement "the pushrods could be spun". They may or may not...if the clearance is so bad, the pushrods won't spin and you'll think you're on the wrong stroke. Watch the intake valve, then look for TDC.

Sorry, I forgot make and model. 1977 R100/7

And yes, this is what I was doing, watching intake valve closing. I followed this Snowbum procedure:

Put the transmission in top gear (4th or 5th, depending if a 4 speed or 5 speed transmission), and rotate the rear wheel in the NORMAL direction, using the gears, etc., backlash ...in other words, jerk the rear wheel, as needed, back and forth, always trying to move the engine in normal direction, until the LEFT INTAKE valve, which is the left rear valve stem, is coming OUTwards ...that means that valve is closing.

Once you've done the left side, you're correct you can rotate the engine until you see the next TDC mark...that SHOULD be TDC for the right side. I never really trust that but actually watch the right intake valve and then go back to the timing window to watch for TDC.

Ya, I think it was good. I know what you mean about checking but going back and forth bugged me too. I thought, I can be sure I'm only doing one rotation if I look right at the OT mark.

IMO I think 39 newton-meters is too much...that's 29 ft-lbs. I'd suggest that you back it down to 25 ft-lbs or 34 newton-meters. And the head bolts are torqued in a criss-cross pattern.

I got that from Chris Harris' video on this and it seems to be reflected in the Clymer Manuel I bought.

I probably wouldn't have set all the torque and valve clearances on the left side until I had actually gotten the right side back together. I can't remember what Oak's manual suggested but I thought he said to put one side together with light torque on the bolts, then do the other side with light torque. Then begin the process of torqueing the first side.

Well, it's done at this point. I think once i get the right side together, I'm going to recheck rocker arm play and valve clearance on the left side and then the right side, so each will get multiple checks.

Don't know about taking the side apart without being at OT...I think it's just harder that way, and the head bolts are under tension a little longer, but probably was OK.

God I hope so. I recall reading something about how you don't have to do this or that if you have it at OT for the side you're working on.

What about valve lash? I keep hearing that from Facebook commenters (I posted there as well). I don't trust a lot of what is said there, it's all over the place and so often people answer questions you haven't asked.

 

[20774]

What about valve lash?

Not sure what you mean...valve lash is valve clearance. The settings should be 0.15mm intake and 0.20mm exhaust.

I'll include the bike model and year in the thread title for future reference.

 

[thdomo]

Thanks, I thought it was lash meant something else.