CX500 GL500 650 Global

I am going to re-post these pictures somehow in the constant velocity carbs section and do a proper write up for LRCXed but I have now a chronic issue that I cannot figure out. I have a 1980 CX500 custom.

The symptom is the bike bogs down when i give it gas.

From the pictures,it is evident that the carb just went through a thorough overhaul.The bike will idle until the cows come home, carbs are balanced.The lines from the tank are new. The filter is new. The tube in the tank is now of the right size.

This symptom is old. But my bike will run like new whenever she feels like it. this is an intermittent problem, as it was running just fine before i ranthe tank empty a month or so ago trying to see how far my new reserve would get me after cutting the petcock tank tube to it's proper size.

A variable in this puzzle I haven't been able to test is the function of the blasted FUEL PETCOCK. I have tested the basic function by blowing air through it while turning the the valve from on to off to reserve: IT WORKS. WHO THE **** KNOWS?

So my next step is to buy a new FUEL PETCOCK ASSEMBLY as a last disparate resort.

Unless this is somehow some evil electrical problem I have NO IDEA where to go with this.

Does anyone have any ideas?

My 1st suspicion is float heights,

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=110

They can go out even after being set and might need re-checking.

Then there's this,

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=10&t=335

vdotmatrix
Sorry to hear your having issues. It is possible there is an electrical issue. But first eliminate the carbs. Have you drained and flushed out the bowls since the problem started. Leave the petcock on and let it flow into a clean container so you can see if anything is flushed out. It is possible there could be debris in there that got by when you drained the tank and messed with the overflow tube. Are you running a filter in the fuel line? It has happened several times after guys have pulled and reinstalled fuel lines too. It can dislodge small pieces of rubber fuel line if your pulling it off of a filter with sharp barbs on the edges of the nipple.
I don't suspect float height as an issue because I don't adjust them by using heat to reposition them. I replace floats if they are needed with one that is the proper setting and has been stable for years. If you want to check it anyway, put a piece of clear tubing on the bowl drain and open the drain screw. With the tubing held up over the top you should have a level that is near the split between the bowl and the body of the carb nearest to the front of the carbs.

If this fails to get good results I would check the electrical system as Shep has mentioned. You can also check the plug caps for intermittent connections due to corrosion.

You can always email me direct if you want to send them back to me and have me re test and check them out.

Larry

This is not a new issue but the same issue with my bike.

This cannot be an issue with the carbs I assume because it has been overhauled. I have the tank strainer and a NEW inline filter and new lines. It feels like the same fuel starvation sensation.

Retracing the fuel brings me to the subject of this post: The fuel petcock (valve).

I guess it either works or it doesn't work. (The bike ran so well before I ran the tank dry but that could be just coincidence.)

I will have to by pass the float concern until I troubleshoot the electrical possibilities; it does seem to be an intermittent issue

You might try checking the gas cap to see if the breather vent is plugged up. That would cause starvation too but in all ranges.

I have to find that vent on the gas cap.

I pulled the carbs, and thanks to LRCXed instructions on how to do this effortlessly, I came across something: The fuel line.

I blow in the direction of flow and there is, to me, a lot of resistance. I blew from the other end and not so much but there is enough to make this a serious consideration.
This is the cheap fuel filter I have by the picture;http://store.knfilters.com/search/product.aspx?Prod=81-0221

I had 2, broke the other one the other night so this too is brand new on the bike.

So, if this is a really cheap crappy fuel filter, if I spent more for the really GREAT filter will the flow characteristics be any different.

Sheppola wrote:My 1st suspicion is float heights,

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=110

They can go out even after being set and might need re-checking.

Then there's this,

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=10&t=335

The bowl on the right side is SPOT ON; i don't think it is a carb problem but I will buy a more expensive fuel filter that may have better flow characteristics.
The tank vent which I guess are the 2 holes in the gas cap are clear.

The next thing I guess will have to be trouble shooting the electrical. It bogs at all speeds.

I go from ZERO TO SIXTY in about 5 miles!!! LOLOLOLOL

well Honda doesn't even list a fuel filter for this bike and all they list is the tank strainer. I hate to do this but I am going to just run a line from petcock to carb and see if this drastically improves performance.

I ran a straight fuel hose sans fuel filter and made no difference...i did have some backfire so i may have to checkvalves and stuff. I drained some fuel into a glass from the tank and the fuel flowed like wine!
there is another issue.