1100 Carbs enrichener circuit flaw

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Finally got around to looking for my "hard start when cold" problem. I was suspecting plugged enrichener circuits (not really a "choke" on the 1100.)

(Pulled the carbs to also check for a suspected coolant link and found the loose clamp on the right bank coolant elbow.)

Turns out, the link between the left bank (where the cable connects) and the right side is too "limp" to fully open #1 and #3 circuits. The link is a small diameter rod with two kinks in it;when it gets pulled, the kinks straighten just a bit rather than pulling the circuits open fully. I checked my shelf set and it does the same. Maybe Ma Honda didn't think bikes get started at temps below freezing.

Usually not a problem above 45? but when it's lower than that, the right bank won't fire 'til there's some heat in the system. Runs fine once warmed up.

I'm thinking a second cable from the right enrichener activator rod to an accessible location, just for those hard start occasions. Other (more involved) fix would be a more stiff link between the two sides.

Any other thoughts?
 

bdalameda

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I have noticed that the enrichener plungers become somewhat stiff to operate due to corrosion and lack of lubrication. This is common on all carbs using this type of enrichener. If you remove the plunger and lubricate the shaft and threaded bushing you may find that it will then work more freely and require much less to pull. This may fix the problem.

Dan
 

sirepair

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Ether injection? (a lil dab will do ya!)

Remake of the rod would be the best, I guess. Billet aluminum!!
 

Ross Smith

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Started mine at -5 C the other day to flush some old gas out of the carbs after sitting idle since November. The bike fired up almost immediately. Don't think there's anything wrong with Honda's enrichener design, but I do think yours may either be worn or is badly out of adjustment.

As John O has asked, got any pix?

Ross
 
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George,
My '91 will start at well below freezing. Open the enricheners, don't touch the throttle, hit the starter button and the engine starts immediately. At 45 degrees F I don't even need the choke to start (idle, yes), throttle 1/8 open hit the button, immediate start. One other thing, mine doesn't get 50mpg either.
 

The Cheese

When I did my carbs I noticed something very similar. The right side would not fully engauge because of the same issue as above. When the linkage was gently forced out, it would hang up. The solution was to clean the enrich valves as much as possible. Very, very lightly sand the brass looking shaft to remove burrs. A small drop of 3n1 oil was added to each brass looking shaft. That helped alot. Did not completly get rid of the binding. It was then found that the linkage for the right side was put on ever so slightly different. Fixed the POs "fixing", and it went back to normal. Have not had another issue since then.
 
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George
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I'll take some pix. There's a lot of slop between #2 & #4, a lot of slop left to right, and more slop between #1 & #3. By the end of the chain, #3 barely moves at all.

The easiest to remove is #3 (?? upside down and left to right, uh)... yes, #3 , so pulled that circuit out. All looks good in there, no corrosion or obvious problem.

I'll go ahead and remove all 4, burnish the rod and add a drop of oil on reassembly. But just the slop in the system deletes a lot of potential movement. Maybe some tiny washers to tighten things up little.

Also, does it need all the possible movement. Seems should only be necessary to pull the plunger off it's seat and all four do that. Hmmmmm, still thinking.

Thanks for the input, guys. Watch this space.
 
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As I recall, there is a rod with "Z" bends that ties the left bank to the right bank at #3 (right rear). There is a larger diameter rod that then ties #3 to #1 that has and adjustment screw where you can set the travel for #1 (right front)

If you loosen this screw - you should be able to get #3 working properly by straightening out the bends in the Z rod. Once that is done, you can then set the travel for #1. There is also the same adjustment on the left bank

not the best pic, but all I could find at the moment
 

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George
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What you say is correct, John, except the bends in the rod are stock, and the adjustment screws are set to tightest tolerance. The adjustment is for #3 as #1 is driven directly by the cross rod. Also, the adjustment screw on the left side is for #1 as #4 is is driven directly by the lever.

Your lower/left arrow shows part of the problem, note the tiny gap between the end of the "brass" rod and the adjustable bracket. Farther to the left is the lever to push those two pieces. Between the lever, the bracket, and the end of the rod there's enuff play to take up a lot of the potential movement. Looks to be a similar gap at the right arrow, #1 enrichener circuit plunger.

Behind the screw driver is the throttle link for the left to right sides. Note there is a "Z" bend in that link too but it's made from much sturdier bar stock. The rod between the side for the enricheners is about 8 gauge steel wire.

Thanks for the pic, John, I'll take a couple more as I fiddle with it.

More to come.

Folks, John's foto is the left side carbs, as ID'ed by the single carb synch screw.
 
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George
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BTW, in the book it's called a Starter Enrichment (SE) Circuit.

In the fuel system troubleshooting guide (pg 5-2), a clogged SE is one of the possibilities but nothing about fixing it.
 
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The first pic is what I found when I pulled out one of the "plungers" for cleaning. After seeing that, I decided I needed to pull all 4 plungers, but the only way to do that is to actually separate the carbs :(

I ended up stripping everything down and gave each carb a good soak in carb cleaner - I was surprised that NAPA and some other stores still sell it by the gallon can with the little parts tray

the other pic is how they turned out and all the parts
 

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George
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The port pictured by John is the air cutoff valve, contains a diaphragm and spring with a cover. The SE is not pictured but the parts are in the third pic.

I found most of my problem. The SE valve lever (part #30, pg 5-8 in the service manual) is the problem. The mount hole is wobbled out just a little adding to the "slop" in the system.

IMG_6235 (1200x674).jpg

I peened the hole to close it up a littlebut still wobbly. So, I ground off the indicated corner to allow more travel. Seems to have taken care of problem.

Checked all 4 SE circuits, no problems found in there. Didn't take anything else apart.

I mentioned this morning I needed to fab a new lever for the Audiovox CC, this is the old one. Just too thin to stand up to constant use. new one is heavier and a little longer.

IMG_6236 (1200x674).jpg
 

Bigmak96

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I mentioned this morning I needed to fab a new lever for the Audiovox CC, this is the old one. Just too thin to stand up to constant use. new one is heavier and a little longer.
Glad you mentioned this George. I was not real happy with the original lever, but didn't think I had seen any post re: failures or concerns. I will pull mine off and fab a new one.
 

Bigmak96

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Are you sure about the"wobbled out" hole? It looks manufactured to me given the straightness of the features.
 
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George
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Just a little too much slop in it, Mark. The threaded post onto which it fits has flats on both sides, but either the diameter is too small or the metal of the lever is too soft for the long term. With a little more travel, the rods on all 4 carbs now extend as they should. I'll try it this afternoon once she's back together.

On the CC lever, it was twisting at the top instead of pulling left under accel. Was still working but weak. the new one is plenty sturdy, made it from an old Honda tool. Pics later.
 

Bigmak96

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I have not looked at that part yet but I wonder if a little thread lock would help with the slop. Or does it need to be a non-rigid attachment?
I am going to make a new CC arm tonight !
 
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George
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I have not looked at that part yet but I wonder if a little thread lock would help with the slop. Or does it need to be a non-rigid attachment?
I am going to make a new CC arm tonight !
I'm sure yours will be a lot more elegent than mine, Mark. :D

On the SE lever, even a perfect fit over the stud probably won't make it real sturdy. Needs more beef.
 
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