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Discussion Starter #43
I'm guessing the solution is to loosen all the adjusters on the left head as far as they'll go and turn the engine slowly to TL watching the push rods. What should I be looking for? My "educated guess" is that if there's any movement as it approaches TL I have it wrong?
 

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Rotate it until you find a huge flapping clearance.

If all you find is a normal clearance on one stroke and open valves on the other they've been set on the correct stroke.
 

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'84 CX650E that is evolving into a GL500
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I've checked the timing by bringing the rotor around to TL and the rockers wiggle as they should.
Did you check at TR as well? You keep referring to the TL mark but the right cylinder's valves need to open at the right point too.

I fear something mechanical is amiss. I don't think there's adequate compression for whatever reason. Can I re-use the head gaskets if I need to remove the pistons again? It's never ran and only been torqued the once with Copper Gasket sealer spray.
We normally frown on asking the same question in more than one thread because it can lead do confusion but I think in this case it won't as long as the threads are cross referenced
 

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Discussion Starter #46
Did you check at TR as well? You keep referring to the TL mark but the right cylinder's valves need to open at the right point too.


We normally frown on asking the same question in more than one thread because it can lead do confusion but I think in this case it won't as long as the threads are cross referenced
You can merge the two if you like,Bob.
 

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Discussion Starter #47
Did you check at TR as well? You keep referring to the TL mark but the right cylinder's valves need to open at the right point too.


We normally frown on asking the same question in more than one thread because it can lead do confusion but I think in this case it won't as long as the threads are cross referenced
To be fair though, I was just asking if I can re-use certain parts but it ended up a cross reference. Merge or delete as you see necessary, Bob. No worries.
 

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'84 CX650E that is evolving into a GL500
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Yeah, I figured this was a case where it might be better to leave them separate as long as they had links to each other.

So did you check that the valve clearances were set at TR compression?
 

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Discussion Starter #49
Yeah, I figured this was a case where it might be better to leave them separate as long as they had links to each other.

So did you check that the valve clearances were set at TR compression?
Not yet, Bob. I have one those lives where my time to do things like that is sparse at best. I'll be posting any results I get from that and compression test as soon as I can get the time. Thanks for lookin' out, Bob.
 

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Discussion Starter #50
I got my cheap compression tester today and gave it a go just to see what happens. I got 125 psi in each cylinder, but that's as far as I got tonight.
 

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Discussion Starter #52
I would think so, but no. Shouldn't it be higher with new rings and lapped valves?
 

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New rings that aren't bedded leak. Compression before first start will usually be low, particularly if the bores aren't absolutely round. A hone can't fix dimensional issues like minor ovality.

They will bed in and your compression will improve once it's running.

One thought I've just had on your non start.

As you've had this completely apart and presumably assembled with copious quantities of oil are you certain it has not oiled the plugs and saturated the insulator?

Trying another set of plugs might be worthwhile.
 

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Discussion Starter #54
New rings that aren't bedded leak. Compression before first start will usually be low, particularly if the bores aren't absolutely round. A hone can't fix dimensional issues like minor ovality.

They will bed in and your compression will improve once it's running.

One thought I've just had on your non start.

As you've had this completely apart and presumably assembled with copious quantities of oil are you certain it has not oiled the plugs and saturated the insulator?

Trying another set of plugs might be worthwhile.
I used moly on alot of the parts that rub. Oiled the pistons/rings on install. Maybe plugs. It blew a feeble flame out the exhaust port when I put petrol in the balance ports. Nothing off the carbs. I can smell the petrol when I did the compression test. Reckon plugs couldn't hurt but it seems to me I should have more happening than there is. I'll give the current plugs a good cleaning for now to see if I get any better results.
 

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New plugs are worth a try. Cleaning oil soaked plugs isn't always successful but also worth a try.

Carb or brake cleaner is good. And running a butane torch over the electrodes wouldn't hurt.
 

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I'll offer something that's probably a long shot and starts with a question - did you paint the frame before re-assembly? I've put a bike together after painting and the the earth / ground was not as good of a connection. It was not noticeable on gauges, lights, switches, but the spark wasn't there and wouldn't start. i pulled all the ignition stuff and someone else said "hey try the ground". Boom! it ran perfect after that. I really coated the frame heavy in a few of the hard to spray places that are not visible to ensure no rust and corrosion. The paint was not a great conductor. Since this started as a potential electrical issue it may be worth just 2 min of sandpaper and reconnecting the ground on the bike. Good luck.
 

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That can quickly be tested with a jumper lead from the battery ground terminal to a clean point on the motor like a valve cover bolt.

But if it cranks it's likely grounded.
 

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Discussion Starter #58
I'll offer something that's probably a long shot and starts with a question - did you paint the frame before re-assembly? I've put a bike together after painting and the the earth / ground was not as good of a connection. It was not noticeable on gauges, lights, switches, but the spark wasn't there and wouldn't start. i pulled all the ignition stuff and someone else said "hey try the ground". Boom! it ran perfect after that. I really coated the frame heavy in a few of the hard to spray places that are not visible to ensure no rust and corrosion. The paint was not a great conductor. Since this started as a potential electrical issue it may be worth just 2 min of sandpaper and reconnecting the ground on the bike. Good luck.
Nope. No paint has been applied. I rebuilt the engine over lockdown and just put it in. Once I get some time I'll have a look but all the ancillaries were taken off an engine that has a knock when hot and put onto the rebuild. Knock aside, the bike ran great. Good carbs, good coils, all sorted with the knocking engine in it. It's just one of those "what did I miss?" things. All things being equal, it should at least start.
 

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It’s been mentioned earlier but I’ll bring it up again, are you sure you had the crankshaft and camshaft lined up properly when you installed the timing chain? You symptoms definitely point to you being off a tooth or more.
 

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Discussion Starter #60
It’s been mentioned earlier but I’ll bring it up again, are you sure you had the crankshaft and camshaft lined up properly when you installed the timing chain? You symptoms definitely point to you being off a tooth or more.
I've been thinking about a tooth off. Do you think I have the symptoms?
 
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