mustering the confidence to do my valve adjustment

[growler]

Eh, kind of. I'll just go back out there this week and take a video. It's the only way to make sure I'm doing this right. Thank you for your effort to explain it.

Ignore those metric APPROXIMATIONS, you have a set that goes down to 0.0015".

Just to help you with some reasoning behind the cam lobe positions: you obviously don't want a lobe pushing on a valve when you are trying to measure clearance. With the lobes in the specified positions, not only is that one not pushing on a valve, the one next to it isn't, either. That keeps the cam somewhat centered in the bearing on that side of the engine. You should note that the valve goes down in the head at about a 45 (or so) degree angle, and the two cam lobes are at about 45 degrees to the valves.

Does it make more sense now? :-k

.

 

[JTGS850GL]

Just do a quick dry run through and it will all make sense. Getting the lobes to be in the right location is the easy part. Getting the old shim out and the new one in, well.... That can be a little more challenging sometimes. I've had a couple engines that you could not rotate the shim bucket on one or more of the valves. Now that can be a little challenging if the slot in the bucket happens to be in just the wrong position. But that's another story.

Don't worry about doing the valves. There's not much you can screw up that can't be undone as long as you remember to not turn the engine over while a shim is out and re-measure each valve gap after you've replaced the shim.

I think the hardest part of doing the valves is getting that darn baked on, stuck on old valve cover gasket of for the first time. Not as bad as a base gasket but still a PITA.

 

[growler]

I am super lucky when it comes to the valve cover gasket coming off easily. Also the engine turns easily. I have a tendency to make things harder than they are. So we all can laugh together when I post a video.

 

[Wingsconsin]

I am super lucky when it comes to the valve cover gasket coming off easily. Also the engine turns easily. I have a tendency to make things harder than they are. So we all can laugh together when I post a video.

I am looking forward to the video - I am a visual learner and that would help me a lot.
But when I am ready to do it (later this spring) I am sure I can tackle it with all the resources we have here.

Question for the masses --
Do you order shims BEFORE you do the job or AFTER you take all the measurements ?
I know Steve sent me my very own copy of his spreadsheet with the current shims inventoried --
So I should be able to order the ones I think I need prior to opening the bike up..
As well as the needed gaskets ...

 

[eil]

I am looking forward to the video - I am a visual learner and that would help me a lot.
But when I am ready to do it (later this spring) I am sure I can tackle it with all the resources we have here.

Question for the masses --
Do you order shims BEFORE you do the job or AFTER you take all the measurements ?
I know Steve sent me my very own copy of his spreadsheet with the current shims inventoried --
So I should be able to order the ones I think I need prior to opening the bike up..
As well as the needed gaskets ...

Unless you have a bunch of extra shims laying around, an 8-valve shim job is at least a three-step process: 1) measure 2) order new shims and wait for them to arrive 3) install new shims and measure again to be sure. I personally think its better to wait on the gaskets until you have everything torn apart and are ready to order shims. That way you have the option of buying the gaskets from the same place you buy the shims. And anything else you might find you need upon giving the bike a good look-over at the same time.

I'm to the reassembly stage of my 850 top-end rebuild at this point. I hope to have to back together enough that I can check the valve clearances by tonight. If I get that far, I'll try take some video to illustrate the process.

 

[Allie]

Unfortunately, Steve's spreadsheet isn't my issue. The positioning of the lobes is what I need help with.

Yes I realize that. Just sayin' once you go through it it will all be pretty straightforward.

 

[Steve]

It also serves as a record of the last time my lazy asp last did the valves.

You have a snake do your valve adjustments? :-k

COOL!! :encouragement:

.

 

[Allie]

You have a snake do your valve adjustments? :-k

COOL!! :encouragement:

.

I guess my secret is out. Mr. Smart Aspertame.

 

[cowboyup3371]

Do you order shims BEFORE you do the job or AFTER you take all the measurements ?

You don't know what you need for sure until you measure what you have then you might be able to move some around so you won't need as much.

 

[growler]

Going to work on this tonight, and will definitely document the process. I think I finally understand.


My old half moons are stuck in there good with some sealer. How should I attack getting them out? I obviously don't want to mar any surfaces. Grab them with a needle nose? Pry them out?

 

[growler]

Replacing gaskets while I'm doing this, of course. This old valve cover breather gasket looks weird. I didn't expect to see anything covering up the wire mesh stuff. Is this normal?

 

[JTGS850GL]

Yes, that's normal. That's the path through the breather and the wire mesh is designed to trap any oil that's being puked out. There are wire pads above and below the gasket.

 

[Wingsconsin]

Once you get this finished you will qualify for advanced level tinkering ! (And feel good too!) :encouragement: :victorious:

 

[JTGS850GL]

Once you get this finished you will qualify for advanced level tinkering ! (And feel good too!) :encouragement: :victorious:

And if you ever have to split the cases then you qualify for MASTER TINKERER!

 

[Steve]

Your " '82" bike seems to have a black engine that looks rather "factory".

You sure it's not an '83? :-k

What was the production date? (found on the VIN plate on the steering stem)

.

 

[growler]

The PO said the bottom end was replaced at some point. Maybe he meant the whole engine was replaced. Wasn't the most mechanically inclined fellow, although he did have maintenance records. He took it in for services, ones that could have been easily completed on his own. The black paint bothered me, as it wasn't stock (as you note). I wanted to paint the engine at some point, probably next year. I'll check out the VIN plate on the steering stem, although I can't guarantee it matches the year of the engine.

Is it ok to just yank out the old half moons with a needlenose? Mine are stuck on there pretty good.

 

[eil]

Is it ok to just yank out the old half moons with a needlenose? Mine are stuck on there pretty good.

Sure. You'll likely have to deal with cleaning the sealant off the head too.

I might catch some flak for this, but if it were my bike and the half moons weren't leaking before, I would be tempted to just leave them. If they do end up leaking, they're pretty easy to change.

 

[cowboyup3371]

Yes, use a pair of needle nose pliers on the rubber or even your fingers and give them a good yank. Use some hondabond on the bottoms when putting the new ones on to seal them properly; the gasket only needs a spray of Wd-40 to help removal later.

 

[Allie]

Going to work on this tonight, and will definitely document the process. I think I finally understand.


My old half moons are stuck in there good with some sealer. How should I attack getting them out? I obviously don't want to mar any surfaces. Grab them with a needle nose? Pry them out?

I I'd consider leaving the half moons alone if they are still soft and pliable, with no apparent shrinkage below the gasket surface level since they're all sealed in. When you yank them out though they are much sturdier than you'd think because it's a rubber coating on a metal form. At least, I seem to remember it that way.

And I ended up making my own breather gasket during my first valve adjustment. Speaking of my first valve adjustment, it was quite a debacle, as documented here:

http://www.thegsresources.com/_foru...&highlight=valve+shim+adjustment+exhaust+stud

I sincerely hope yours goes better though I am pleased that, like The Princess Bride, it had a happy ending. And it's a testament to the kindness and patience of these folks.

Hahah, I never did get around to removing that broken exhaust stud... guess I'm a slacker.

 

[growler]

I'm happy to report that the light bulb was hovering above my head last night as I finally completed checking the clearances. Not only that, I actually understand what the heck I was doing. Who knew? Once everything clicked and I mastered the shim tool, life was good. Thanks everyone for your patience and help!

I made a few short videos that I'm going to edit this evening. Will post as soon as it's complete. Nothing special, but it may help someone.

I'm going to plug this information into Steve's spreadsheet, but here are my results in simple text. It's worth noting that my smallest feeler gauge is 0.04mm. Also when I say <0.04mm (maybe 0.03mm) it means that the 0.04mm gauge is pretty close to sliding under the lobe and across the shim, but doesn't. I'm guesstimating the 0.03 possibility because the gauges feel similar to when I was checking and a 0.06mm didn't fit, but the 0.05mm did. Hope that makes sense.




Intake 1: <0.04mm (maybe 0.03mm) Bucket with shim rotates easily by hand.
Current shim size: 2.55
Exhaust 1: <0.04mm (maybe 0.03mm) Bucket with shim rotates easily by hand.
Current shim size: 2.60
---------------------------------------------------
Intake 2: 0.05mm
Current shim size: 2.55
Exhaust 2: 0.05mm
Current shim size: 2.55
----------------------------------------------------
Intake 3: 0.05mm
Current shim size: 2.55
Exhaust 3: 0.05mm
Current shim size: 2.60
---------------------------------------------------
Intake 4: <0.04 (maybe 0.03mm) Bucket with shim rotates easily by hand.
Current shim size: 2.50
Exhaust 4: 0.05mm
Current shim size: 2.55



Also, my half moons were hard and brittle. Yanked them out and have replacements. Where do I get the correct bond to put on the bottom of them when replacing? Regular auto parts place?