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Old 01-29-2013, 05:17 PM   #31
khale OP
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Originally Posted by khale View Post

Left side, looks off?

When I was putting the head back on last night after inspection of the valves, I put the rocker arm/shaft in place and from what memory serves me, I had room left on the exhaust rocker adjuster screw. I wish I had taken a picture so I could verify it 100%.
If my adjuster screw does now in fact have room left, could it have meant that I just didn't align my rocker shaft correctly, or anything else? Sorry, I know this is a tricky issue to diagnose.
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Old 01-29-2013, 06:08 PM   #32
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With the adjuster screwed in that far, the exhaust valve has to be sinking into the seat. You can't determine that without disassembling the head.
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Old 01-29-2013, 06:17 PM   #33
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Originally Posted by khale View Post
Appreciate the thoroughness. This all helps me a lot. I guess I should have stated I'm not entirely a novice when it comes to mechanics, but I'm absolutely not on the level of Click/Clack. I own many tools, including a torque wrench.
[deep south southern draw]Don't tell them boys from the UK about a torque wrench. Evidently they have a genetic mutation that enables them to torque by feel. We 'Merican's are the only ones that need torque wrenches.[/deep south southern draw]

IMHO, I'd say button it back up and watch your valve adjustments every 500-1000 miles. From the pictures I've seen, I don't think you need head work.It looks like your valves and seats look good. If there's no wiggle of the valve in the guide with the spring removed and no exhaust blow by, I'd say you're good. If you want another opinion and you're an ABC member, I'd bet you could email Oak for another opinion: that might be helpful. It might be worth running the adjustment issue by him as well.
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Old 01-29-2013, 09:43 PM   #34
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I'm guessing this pic was taken with the valve spring in place and somehow compressed... and that no measurement of the valve stem and guide bore was taken...
I'd like to be wrong in that assumption.

If my guess is right, then it would be difficult to feel the slop in the clearance, etc.
It would be a drag to carry on with a worn valve stem & guide till the valve head separates, noisily beating the piston to death, AMHIK.

but then again it may be fine till the next inspection.

in the pic, that little bit of valve seat looks sort of recessed... but maybe the image is misleading.
my best guess is bmwrench has it right.

The cylinders on my old /5 were so tapered we went from standard to 2nd over, though that engine was running pretty well before I tore it down for head work.
(not the same engine that swallowed a valve).

Originally Posted by khale View Post
Exhaust valve open.
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Old 01-30-2013, 03:19 AM   #35
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If you haven't put it back together yet can you take a few more pics? You have the valve out from the looks of the first photo. Take pic of seat with out valve and valve out of head. Please.
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Old 01-30-2013, 05:20 AM   #36
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My head with the same valve adjuster issue looked surprisingly "good" upon disassembly, valve guide wear aside.

I expected serious seat recession, or heavy valve tuliping but could only see some heavy burning.

Not an easy thing to measure either, e.g., compared to the other head. I guess it's a sum of a number of small faults, rather than one glaring one--best left to a real machinist, not an amateur like me.
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Old 01-30-2013, 05:54 AM   #37
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I guess Khale has put it back together now so the answer will have to wait.

I often leave out the story of some of the nonsense I'm capable of. I have mentioned that I have two sets of heads for my bike. I had the original ones off and was trying to replace the rings. I ended up with new 2nd over sized pistons, rings, honed cylinders. And my old worn out set of heads. The main problem with my heads seemed to be the guides were a little too worn.

I found another set with better guides but worn out exhaust valves, I thought. So I bought a new pair of exhaust valves and lapped them into the seats. That's what I've been running for the past 20K. Runs fine.

One of these days I will try putting guides in. I need the proper type reamer. I have the other stuff. But I figure both sets of heads now need new seats or that's what I think I want and I know we can't do valve seats. We might do valve guides but it seems few riders do this any more.

Going to set the valves later today but the main project is to paint the inside of my fairing. Temp will be almost 70* I think. Then it's going to turn Winter again tomorrow.
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Old 01-30-2013, 06:12 AM   #38
Bill Harris
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Originally Posted by Disston
You let the machinist provide valves, guides and seats...
Originally Posted by Chollo
If Bud is doing your heads, I'd let him provide anything head related...
+1 on Disston and Chollo. Unless you are planning to buy expensive valve tools and add decades of experience, you'll want the shop to do the entire job and not simply press new seats in.

Too bad we didn't get to see the valves and seats...

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Old 01-30-2013, 05:17 PM   #39
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Seat recession, valve tuliping, or valve stem stretching (even breaking) is a known problem on older airheads.

But another problem is that the posts the rockers sit on creep inwards.
They are a press/fit steel bushing in the alloy heads and over time they tend to do so.

So check the height of those posts on the affected side, and compare with the other, which look ok.

I had similar problems with the heads from my old /5, should have taken a few pic's for posterity, but they ended up in the bin before I thought of that.

Geht net, gibbet net.
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