Venturer Adventure

[Radioguylogs]

I'm curious to hear Mike, what sort of fuel economy does your venturer normally get? I just did a decent jaunt on my '79 with a windshield and soft saddlebags mounted up and could never get more than 36mpg even when keeping speeds closer to 65.

I didn't pay exact attention, but I think it ranged between 33 and 40MPG depending on how much I stopped and how fast I rode.

[Radioguylogs]

Drawing #2 is not good, there is a good chance it will cause the carb to flood.

Maybe try turning that clip around 180 deg, I believe they fit better one way than the other. Also maybe adjust the drop-down tang so the float cannot drop low enough for that clip to get cocked into that position.

I was wondering when I put the needles on the tab if the orientation mattered. I did them all them in all the direction.

I ordered new floats and float pins. When I put them in, I'll try rotaing the needles 180 degrees and see if they avoid the NG position.

I didn't pay attention to the drop down tangs, so that may be an important suggestion.

Thanks for he help.

[Ranger_xs1100]

Radioguylogs, Thanks for an enjoyable thread. The writing and the scenic pictures are great. Sounds like a fun adventure. (Except for the unfortunate mechanical distractions!)

[bikerphil]

I didn't pay attention to the drop down tangs, so that may be an important suggestion

Very important. The floats really don't need to drop down very far, just enough to dislodge the needle from the seat. Plenty of fuel will get by with just a slight drop. Then there will be no chance of that clip getting cocked.

[Radioguylogs]

Today I did some of my homework.

* I ran the bike and pulled on the pickup coil wires again. No problem there

* I check the centrifugal ("lazy susan") spark advance...and it wasn't there. I had forgotten the spark box replaced that function in later models. So, no problem there either. I confimed the vacuum advance was working correctly.

Now I can pull the carbs and note the drop down position of the floats, and evaluate the propensity for the needle valves to become cocked on the float tab.

[Radioguylogs]

I pulled the carbs and studied the movement of the floats and the relationship with the drop down tangs.

None of the tangs appears to been adjusted. They are all perpendicular to the surface of the sheet metal. The floats all hang such that the top of the float is even with the gasket surface:




I tried moving the wires around the end of the tabs, like the bottom sketch in my previous post. Even when the wire is cocked over the end of the tab, the floats are able close the needle valve normally.

I discovered that #3 float is bent such that one of the two bulbs can rub the carb body if it is biased to one side. I think this is probably why #3 has been the problem child:




I studied the orientation of the needle valve wire on the float tab. I found that the way I oriented them was less desirable and more likely to have the wire get off the end of the tab. The float on the left is preferred, and the float on the right is the way I had them:




By horsing around with the action of the floats, I discovered every float can wedge stuck if it is pushed up beyond the closed position. It wedges in the area in the picture below.



I wonder if #3 stuck open, could it flood the other bowls and jamb the floats shut? I don't think so, because gas would have to flow through the air box while the bike is running; it seems improbable to me.

The bowl gaskets did squish 1/32 out into the float chamber. I'll reuse the same gaskets and trim them flush.

I had already ordered new floats, new float pins, and new needles when I got back from the trip,... berfore I had collected thoughts from you guys. I would have accidentally fixed the #3 float without understanding the root cause. I may or may not have installed the needle valve wires in the right direction, but now I know the preferred direction.

I am hopeful that fixing the floats and the needles will solve the stuck float problem, and maybe the "died while cruising steady" problem.

However, I am skeptical the floats were causing the problem at lower RPM. The problem happened consistently every time I accelerated briskly, and it was in the consistent range of RPM. We ruled out the pickip wires. The mechainical spark advance is OK, so I think I will make sure I buy another Igntion Control Module and have it on the next trip. I had a 2H7 on this trip, but I really need to have a 4RO. I also wondered if a battery problem could behave like this. On the other hand, maybe was a small piece of crud in the pilot circuit. This problem seems to be a mystery for now.

[DEEBS11]

Interesting. I'm not sure if the float could jam up in there (which is in the "gas shut-off position") with all the heat and vibration but it's possible. After parts, a good pilot circuit cleaning and sync, you should be greatly improved. If not, it has to be electrical.

Make sure the vent system is clear. A bug or dirt can get trapped in a vent hose and it will act like vapor lock.

[DEEBS11]

You never had just one cylinder die. It was the entire engine. That points to supply. Might still be a petcock problem. They might need cleaning or a rebuild. Are yours stock?

[DEEBS11]

They look stock. I would work in here also after testing the carb rebuild. However, if one side was hanging up it would only block fuel to two carbs unless you have a crossover.

[Radioguylogs]

Deebs:

Thank you for your suggestions.

Petcocks are aftermrket manual type. They are relativley new.

When I first put the bike back on the road 5 years ago, I had that incident where #3 float stuck open while I was riding and it caused the engine to die. It makes me ponder how one or two cylinders can kill the others.

PS: What are you doing up so early? I try to get to bed by then!

[Radioguylogs]

Some history with this bike (if you have lots of extra tme

https://xs11.club/forum/idle-talk-forum/xs11-xj11-discussion/863938-fluke-failure

https://xs11.club/forum/idle-talk-forum/xs11-xj11-discussion/49009-detroit-venturer-project/page8

[DEEBS11]

Mike, I go to bed at 8:00PM and get up between 3:00AM-4:00AM every day for the last 25 years. I get more done that way. I guess I remember you mentioning the manual petcocks in the past. I run those too and love em. I hope you find the issue with your bike. I will be here every morning 7 days a week if you need me.