Author Topic: Slight hang in idle after carbs rebuilt?  (Read 8570 times)

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Offline BomberMann650

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Re: Slight hang in idle after carbs rebuilt?
« Reply #25 on: June 14, 2017, 07:45:54 PM »
When in doubt, upgrade!  8)
Lol oh man... I know but then I have to do valve springs and possibly hard weld rockers... ugh I'm broke dude. I can't be doing this right now.

We already learnt here that stiffer valve springs are not a necessity.
If you can't find a 650 cam I have some useable 550 spares.

Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #26 on: June 15, 2017, 02:42:15 AM »
When in doubt, upgrade!  8)
Lol oh man... I know but then I have to do valve springs and possibly hard weld rockers... ugh I'm broke dude. I can't be doing this right now.

We already learnt here that stiffer valve springs are not a necessity.
If you can't find a 650 cam I have some useable 550 spares.

How can you tell if you're getting a real 650 cam? My current cam is marked r9 and some guy is trying to sell a "r9 650 cam" on eBay.


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Offline DaveBarbier

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Slight hang in idle after carbs rebuilt?
« Reply #27 on: June 15, 2017, 04:54:51 AM »
It's hard to tell, but from what I can see it's functioning normally. When you squeeze the bow the screw turns.

Are you certain the tensioner is seated in it's little pocket in the lower case? It has a lot of movement, possibly more than normal.

Also, I didn't see the little M6 bolts attaching the head to the jugs on the intake side, using those? Won't cause your problem but if you're leaving out bolts it could be hinting at other things not being up to snuff. Not knocking you, just trying to point out possible issues.

Drop the pan and look up by the crank. You should not see the tensioner end.

Read dave500's posts in this thread for proper tensioner location. http://forums.sohc4.net/index.php?topic=113772.0

There was a member recently that removed and I believe reinstalled the tensioner without raising the jugs as is normally required. I forget who and where the link is, but he said he made a little fixture or something. I can do a little searching if you need to remove the tensioner.

All that being said, when I've been putting cams in and the tensioner is relaxed against the chain, my cam chain is still tight. I wouldn't be able to rotate the cam back and forth like in your video. Maybe your chain is too stretched. I have heard of people using a heavy duty split chain so they don't have to split the cases. Could be an option for you.

Offline Lostboy Steve

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Slight hang in idle after carbs rebuilt?
« Reply #28 on: June 15, 2017, 06:04:32 AM »
It's hard to tell, but from what I can see it's functioning normally. When you squeeze the bow the screw turns.

Are you certain the tensioner is seated in it's little pocket in the lower case? It has a lot of movement, possibly more than normal.

Also, I didn't see the little M6 bolts attaching the head to the jugs on the intake side, using those? Won't cause your problem but if you're leaving out bolts it could be hinting at other things not being up to snuff. Not knocking you, just trying to point out possible issues.

Drop the pan and look up by the crank. You should not see the tensioner end.

Read dave500's posts in this thread for proper tensioner location. http://forums.sohc4.net/index.php?topic=113772.0

There was a member recently that removed and I believe reinstalled the tensioner without raising the jugs as is normally required. I forget who and where the link is, but he said he made a little fixture or something. I can do a little searching if you need to remove the tensioner.

All that being said, when I've been putting cams in and the tensioner is relaxed against the chain, my cam chain is still tight. I wouldn't be able to rotate the cam back and forth like in your video. Maybe your chain is too stretched. I have heard of people using a heavy duty split chain so they don't have to split the cases. Could be an option for you.
Are you talking about the little one in between the intake manifolds? It's there. I try to make it a point to always put every bolt back.

I pulled the tensioner out a bit to try to get a better view of its condition. I was worried about all the slop in the adjuster shaft.

You know Dave, when I first put this thing together the bottom of my tensioner was pretty messed up and I straightened it all out and put it back in. That's probably why it was like that. I have to pull the head anyway because the #$%*ty vesrah headgasket is leaking.


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« Last Edit: June 15, 2017, 06:10:19 AM by Lostboy Steve »
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Offline DaveBarbier

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Re: Slight hang in idle after carbs rebuilt?
« Reply #29 on: June 15, 2017, 08:03:16 AM »
Yeah I was talking about that small bolt. Ok, I just didn't see it, my mistake.

Gasket leaking where? On the sides where the oil galleries are? If so, do yourself a favor and get OEM o-rings for those. The ones in the vesrah kit are often too thin to seal.


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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #30 on: June 15, 2017, 08:22:06 AM »
Yeah I was talking about that small bolt. Ok, I just didn't see it, my mistake.

Gasket leaking where? On the sides where the oil galleries are? If so, do yourself a favor and get OEM o-rings for those. The ones in the vesrah kit are often too thin to seal.


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I've had a very small weep around cylinder 1 or 2 for a while now. I used the recommended torque with ape studs and have been advised by cal and other guys to retorque but now it looks like part of the headgasket is squishing out inside the timing chain galley. Idk if it's just a tab that hangs off the gasket or what but at this point I may as well. I'll get a mls job for the reassembly.


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Offline BomberMann650

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Re: Slight hang in idle after carbs rebuilt?
« Reply #31 on: June 15, 2017, 09:12:00 AM »
When in doubt, upgrade!  8)
Lol oh man... I know but then I have to do valve springs and possibly hard weld rockers... ugh I'm broke dude. I can't be doing this right now.

We already learnt here that stiffer valve springs are not a necessity.
If you can't find a 650 cam I have some useable 550 spares.

How can you tell if you're getting a real 650 cam? My current cam is marked r9 and some guy is trying to sell a "r9 650 cam" on eBay.

Lobe sizes.
They aren't much bigger, but they are bigger.

I hope people arent trying to pull a con 😑

Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #32 on: June 15, 2017, 09:46:13 AM »
When in doubt, upgrade!  8)
Lol oh man... I know but then I have to do valve springs and possibly hard weld rockers... ugh I'm broke dude. I can't be doing this right now.

We already learnt here that stiffer valve springs are not a necessity.
If you can't find a 650 cam I have some useable 550 spares.

How can you tell if you're getting a real 650 cam? My current cam is marked r9 and some guy is trying to sell a "r9 650 cam" on eBay.

Lobe sizes.
They aren't much bigger, but they are bigger.

I hope people arent trying to pull a con
That's what it seems like....


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Offline DaveBarbier

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Re: Slight hang in idle after carbs rebuilt?
« Reply #33 on: June 15, 2017, 10:00:26 AM »
Yeah I was talking about that small bolt. Ok, I just didn't see it, my mistake.

Gasket leaking where? On the sides where the oil galleries are? If so, do yourself a favor and get OEM o-rings for those. The ones in the vesrah kit are often too thin to seal.


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I've had a very small weep around cylinder 1 or 2 for a while now. I used the recommended torque with ape studs and have been advised by cal and other guys to retorque but now it looks like part of the headgasket is squishing out inside the timing chain galley. Idk if it's just a tab that hangs off the gasket or what but at this point I may as well. I'll get a mls job for the reassembly.


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For MLS you'll have to remove the head and cylinders and get them decked. Surface has to be pretty much perfect.

You could easily do OEM. OEM Honda gaskets have a heat activated adhesive so don't use any spray or coating on it.

Offline BomberMann650

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Re: Slight hang in idle after carbs rebuilt?
« Reply #34 on: June 15, 2017, 10:25:44 AM »
When in doubt, upgrade!  8)
Lol oh man... I know but then I have to do valve springs and possibly hard weld rockers... ugh I'm broke dude. I can't be doing this right now.
We already learnt here that stiffer valve springs are not a necessity.
If you can't find a 650 cam I have some useable 550 spares.
How can you tell if you're getting a real 650 cam? My current cam is marked r9 and some guy is trying to sell a "r9 650 cam" on eBay.
Lobe sizes.
They aren't much bigger, but they are bigger.
I hope people arent trying to pull a con
That's what it seems like....

The casting marks are confusing.  They're all r9 or r10.

Mine came from a knowledgeable salvage op.  Had the engine serial in the ad.

Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #35 on: June 16, 2017, 05:58:54 PM »




A ton of fuel inside my air box, and the pistons are black with hard soot. The orings for the oil passages are hard as a rock. All of this stuff is only 6000 or so miles old. The cylinders still look good but are a dark gold color. Overheating? Very weird. Anyway, tensioner is ok it seems but was not adjusting correctly. The gear wasn't making full contact. A bigger worry at this point is the amount of slop in the primary chain. Of I look down into the engine the chain says a bit and if I put it in gear an rotate the back tire it probably has at least 1/2" of slop in it.

Where do I go from here? All that soot didn't build up just since I redid the carbs, but it's been running great with awesome power for what it is.


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Offline BomberMann650

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Re: Slight hang in idle after carbs rebuilt?
« Reply #36 on: June 16, 2017, 10:55:43 PM »
What fuel have you been feeding it?

My test for the primary chain (since there is no spec for them) was to push it towards the case.  Reaching up from the oil pan.  If it makes contact, worn out.  If it goes tight before touching the case -> Ok

Unfortunately for me, my ok primary chain is in a not okay lower assembly  :o

Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #37 on: June 17, 2017, 01:52:50 AM »
What fuel have you been feeding it?

My test for the primary chain (since there is no spec for them) was to push it towards the case.  Reaching up from the oil pan.  If it makes contact, worn out.  If it goes tight before touching the case -> Ok

Unfortunately for me, my ok primary chain is in a not okay lower assembly  :o

Just plain old regular.


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Offline TwoTired

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Re: Slight hang in idle after carbs rebuilt?
« Reply #38 on: June 17, 2017, 09:06:18 AM »
The air plenum has a drain hose.  Is that blocked?  Or not routed to the bike's low point?

Sucking in extra raw gas will certainly soot up the chambers.

Carbs overflowing can fill either the air plenum or the piston chambers.

You have carb issues to deal with, I'd say.  Float setting, float valve leakage, and perhaps fuel tank valve leakage.


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Offline Lostboy Steve

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Slight hang in idle after carbs rebuilt?
« Reply #39 on: June 17, 2017, 05:14:02 PM »
The air plenum has a drain hose.  Is that blocked?  Or not routed to the bike's low point?

Sucking in extra raw gas will certainly soot up the chambers.

Carbs overflowing can fill either the air plenum or the piston chambers.

You have carb issues to deal with, I'd say.  Float setting, float valve leakage, and perhaps fuel tank valve leakage.


Cheers,

Thank you for the reply. I really appreciate it. The plenum drain is clear it's not soaked, but just damp with fuel. I shouldn't have said a "ton of fuel". I used the 4 into 1 carb kits, which are obviously cheaper, I wonder if the float valves are junk? Could explain my hanging idle and all the soot. Now that they're off I will again check the float height with the clear tube method and see what's happening. Any insight as to why those oil passage orings are hard as a rock after just a couple of years?


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« Last Edit: June 17, 2017, 05:17:37 PM by Lostboy Steve »
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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #40 on: June 18, 2017, 05:49:34 AM »
My tensioner is broken. As I had mentioned when I initially took it out years ago the bottom looked a bit mangled. I just tried to straighten it out more and one of the little fingers broke. Also, the slipper is discolored where the chain rides. I'm worried it ate trough too far. Does this look salvageable?





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Offline DaveBarbier

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Re: Slight hang in idle after carbs rebuilt?
« Reply #41 on: June 18, 2017, 06:14:45 AM »
This an option? It's got 3 watchers already. For like $40 I'd grab it. Aren't these tensioners hard to come by?

https://www.ebay.com/itm/182621578749

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Re: Slight hang in idle after carbs rebuilt?
« Reply #42 on: June 18, 2017, 06:18:24 AM »
But yeah, looks like someone didn't have it in the pocket in the case and then cranked it down or something. I bet it could be straightened out and work ok. It's just a locator and doesn't see much stress. The tensioner slipper part seems pretty warn. But if you fix it and put it in place properly then I might still last a while.


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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #43 on: June 18, 2017, 07:16:26 AM »
This an option? It's got 3 watchers already. For like $40 I'd grab it. Aren't these tensioners hard to come by?

https://www.ebay.com/itm/182621578749
Yeah I saw that one last night. Maybe I will.


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Offline BomberMann650

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Re: Slight hang in idle after carbs rebuilt?
« Reply #44 on: June 18, 2017, 11:14:30 AM »
This an option? It's got 3 watchers already. For like $40 I'd grab it. Aren't these tensioners hard to come by?

https://www.ebay.com/itm/182621578749

Yeah that was a damn good deal on a tensioner mechanism.
It has ended unfortunately.

Offline DaveBarbier

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Re: Slight hang in idle after carbs rebuilt?
« Reply #45 on: June 18, 2017, 11:34:15 AM »
Steve, was that you that bought it?


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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #46 on: June 18, 2017, 04:40:39 PM »
This an option? It's got 3 watchers already. For like $40 I'd grab it. Aren't these tensioners hard to come by?

https://www.ebay.com/itm/182621578749

Yeah that was a damn good deal on a tensioner mechanism.
It has ended unfortunately.

lol that's because I bought it. ;)


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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #47 on: June 18, 2017, 04:41:03 PM »
Steve, was that you that bought it?


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Yes sir.


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Offline Lostboy Steve

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Re: Slight hang in idle after carbs rebuilt?
« Reply #48 on: June 18, 2017, 04:43:04 PM »
Steve, was that you that bought it?


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Yes sir.


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I'm going to replace the bow on it with the 4 into 1 bow and keep the other one on display with my other personal collection of broken stuff.


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Offline jonda500

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Re: Slight hang in idle after carbs rebuilt?
« Reply #49 on: June 18, 2017, 07:23:56 PM »
Ha ha - personal collection of useless broken sohc parts - I have an extensive collection of these too, I'm not sure why, but you just never know right?
John
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