Author Topic: What order do you check timing carb sync and idle adjustment... (Read 3613 times)

juntjoo · « **Reply #25 on:** April 01, 2018, 08:20:33 PM »

I was never able to do anything with rubber bands and never saw nor read about them being used on my model so maybe doesn't apply.

I've no clue about the rest of what you said as I've barely inspected valves ever so tonight I'll read up and start digging in tomorrow. Thanks

goldarrow · « **Reply #26 on:** April 01, 2018, 08:47:28 PM »

Check the plug wire is good along the length?

One of the previous bikes I had, spark plug wire broke internally and obviously that cylinder didn’t fire.

juntjoo · « **Reply #27 on:** April 01, 2018, 10:19:15 PM »

Quote from: goldarrow on April 01, 2018, 08:47:28 PM

Check the plug wire is good along the length?

One of the previous bikes I had, spark plug wire broke internally and obviously that cylinder didn’t fire.

I put the one from #4 on it for no difference so I think that rules that out, thanks

Paintedseat · « **Reply #28 on:** April 02, 2018, 08:24:52 AM »

Have you tested to make sure the floats are working and the needles are sealing?

juntjoo · « **Reply #29 on:** April 02, 2018, 09:10:36 AM »

Quote from: Paintedseat on April 02, 2018, 08:24:52 AM

Have you tested to make sure the floats are working and the needles are sealing?

Yes, checked that on #1, and I checked 4 only cuz I had it open. Should I check 2 & 3 even only 1 isn't firing? Off to do compression...

Here's results from a month ago:

compression 1,2,3 & 4 https://imgur.com/a/MXrkx

compression after oil added 1,2,3 & 4 https://imgur.com/a/9uezu

Paintedseat · « **Reply #30 on:** April 02, 2018, 09:33:16 AM »

Are you slides installed correctly. You can turn the 180 degrees the wrong way.

juntjoo · « **Reply #31 on:** April 02, 2018, 10:03:30 AM »

Quote from: Paintedseat on April 02, 2018, 09:33:16 AM

Are you slides installed correctly. You can turn the 180 degrees the wrong way.

Yes, as mentioned I swapped those parts and cleaned with those of #4, thanks.

But how do I get this out??

https://imgur.com/a/N3L5q

Why did they make them like this so you could lose the adapters in there?? I should make a harbor freight employee come out here and take it out. Unless I'm doing something wrong. Totally possible lol.

Anyway, once I get it out I'll report back on compression. So far looks BAD

juntjoo · « **Reply #32 on:** April 02, 2018, 10:11:27 AM »

And how do you make sure they're snug enough so they're air tight(to give accurate readings) yet not so tight I lose the adapter?

juntjoo · « **Reply #33 on:** April 02, 2018, 12:15:32 PM »

https://imgur.com/a/U5EHj

Thank God for these. Barely could fit tho

juntjoo · « **Reply #34 on:** April 02, 2018, 02:32:18 PM »

https://imgur.com/a/xNOIU

After adding oil:

https://imgur.com/a/A4rLt

I didn't include #1 as it produces ZERO compression. Explains the cold pipe.

So I guess I'll be quadruple check the clearances. I'll be back...

juntjoo · « **Reply #35 on:** April 02, 2018, 03:05:42 PM »

So what am I looking for? Clearances for #1 are perfect. How do I suddenly have zero compression? What's the manual check I can do rotating the shaft? From my view things look like they're moving up and down as they're supposed to. What broke where when and how?

Paintedseat · « **Reply #36 on:** April 02, 2018, 03:27:30 PM »

That sucks. You're going to have to pull the cover.

crazypj · « **Reply #37 on:** April 02, 2018, 03:31:00 PM »

Clearances don't mean anything as you've adjusted things multiple times.
Valve on number one is probably stuck open.
Look at the retainers as see if one is in slightly different position compared to the others. It won't be much, probably less than 1mm. About the only other thing I can think of (except a carb screw fallen out and jamming valve open) is burned exhaust valve, I kinda remember the Stellite on 'later' Honda valves (1978 on)being a bit thin
Oh, are any of the adjuster screw obviously down further? They should all be at about same level to about 1/4 turn, one way further down or up will tell a tale

juntjoo · « **Reply #38 on:** April 02, 2018, 04:03:36 PM »

Quote from: crazypj on April 02, 2018, 03:31:00 PM

Clearances don't mean anything as you've adjusted things multiple times.
Valve on number one is probably stuck open.
Look at the retainers as see if one is in slightly different position compared to the others. It won't be much, probably less than 1mm. About the only other thing I can think of (except a carb screw fallen out and jamming valve open) is burned exhaust valve, I kinda remember the Stellite on 'later' Honda valves (1978 on)being a bit thin
Oh, are any of the adjuster screw obviously down further? They should all be at about same level to about 1/4 turn, one way further down or up will tell a tale

Screws look the same. How does a carb screw get in the valves? Okay, I'll do a measurement comparison between # 1 & 4 of how far the valve returns up.

juntjoo · « **Reply #39 on:** April 02, 2018, 04:09:36 PM »

And when you say burnt valve, that's something I've time no? This bike was running hot on all fours just a couple days ago. So I'm thinking I've got bent valves I had somehow managed to tune the bike to compensate for to make it work. If anyone has a clue pls share. Looks like I'm going in though

crazypj · « **Reply #40 on:** April 02, 2018, 04:13:02 PM »

Quote from: juntjoo on April 02, 2018, 12:15:32 PM

https://imgur.com/a/U5EHj

Thank God for these. Barely could fit tho

Those things are evil, wait til you snap one. If it worked, you didn't really need it as part was 'loose'

Quote from: juntjoo on April 02, 2018, 04:03:36 PM

Screws look the same. How does a carb screw get in the valves? Okay, I'll do a measurement comparison between # 1 & 4 of how far the valve returns up.

Usually a choke flap screw fallen out but could be anything if bike was left without carbs and someone 'helped'

juntjoo · « **Reply #41 on:** April 02, 2018, 04:26:52 PM »

So I compared #1&4 valve distances from where the rockers connect to the top of the valve cover and for both intake and exhaust they were identical.

crazypj · « **Reply #42 on:** April 02, 2018, 05:44:03 PM »

Well, that's good, changing valve guides isn't too much fun even if it is relatively easy.
Looks like your 'going inside' soon. At least it's easier than CB750 where engine has to come out to get head off

juntjoo · « **Reply #43 on:** April 02, 2018, 05:54:05 PM »

Quote from: crazypj on April 02, 2018, 05:44:03 PM

Well, that's good, changing valve guides isn't too much fun even if it is relatively easy.
Looks like your 'going inside' soon. At least it's easier than CB750 where engine has to come out to get head off

Did you suggest valve guides to be the problem because my last finding? Excuse me as I'm just learning about valves

crazypj · « **Reply #44 on:** April 02, 2018, 06:13:45 PM »

If valve is bent and sticks in guide it usually damages guide. If everything looks straight and is moving, guides are probably OK

juntjoo · « **Reply #45 on:** April 02, 2018, 06:54:40 PM »

K thanks. I'll just take a lot of pictures.

juntjoo · « **Reply #46 on:** April 10, 2018, 01:34:40 PM »

I haven't done anything so far. No time atm but I'm wondering how this could have happened.

Remember that before I went in to redo the clearances it was running great then upon opening it up I find the clearances were too much at least on #1 and another or two cylinders. Adjusted then torqued to spec this time now no compression on #1.

So my question is how does excessive clearance(before I "fixed" clearance on #1) result in GOOD compression?

My guess as I've mentioned previously is that the valve had been bent or something(you tell me, IDK valves) to where somehow less(more clearance =less?) rocker movement not fully opening valve, but adjusted correctly(with bent valve) opens valve too much causing compression loss. Does that make sense? And how much a gap in there is needed to go from adequate compression to suddenly none?

Paintedseat · « **Reply #47 on:** April 10, 2018, 02:54:27 PM »

You may have adjusted too tight.

juntjoo · « **Reply #48 on:** April 10, 2018, 03:16:48 PM »

Quote from: Paintedseat on April 10, 2018, 02:54:27 PM

You may have adjusted too tight.

I doubt that but really thats possible? You mean like from the last turn to tighten it then maybe I got frustrated re-checking in it and just said 'now THAT'S DONE!'? Cuz that is possible come to think of it. But I was turning the screw like a pinch at most a time and tightening the. So this could cause it to bend JUST enough completely lose compression? How things work never cease to amaze me

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Author Topic: What order do you check timing carb sync and idle adjustment... (Read 3613 times)