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Discussion Starter #1
So my carbs were completely cleaned. accelerates perfectly. Just pops on deceleration. I pull the choke slightly and it goes away when riding. Although at idle. Rpms are high. If I open up the mixture I’m afraid I will loose power accelerating. I’m open 2.5 turns. 120/90 and pods. I’m thinking it’s my exhaust or leak there
200942
 

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Exhaust leak is one possibility, the ACVs in your carbs are another.
 

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Discussion Starter #3
The acv's looked to be in good shape when I rebuilt the carb. It is running a bit on the lean side based on plug color. I can't seem to richen it up with the mixture screws. I wonder if going to 95 jets instead of 90's will help it and keep the 120's. It accelerates great. I will see if I have a leak at the boot intake.
 

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Discussion Starter #4
I have two sets of carbs. One is slightly different. It has an ACV and needle exiting off the float bow. My other set doesn't have that. Not sure what it does. Looks like it needles down to the throttle area.
 

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Discussion Starter #5
Exhaust leak is one possibility, the ACVs in your carbs are another.
Here’s the results of the spray test. Slight rise in rpm at the carb to rubber left side. When I spray at the intake gasket to header, I can choke it out with the spray. All good on the other side.
200947
 

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I have two sets of carbs. One is slightly different. It has an ACV and needle exiting off the float bow. My other set doesn't have that. Not sure what it does. Looks like it needles down to the throttle area.
None of the carbs that came with these bikes have air cuts on the float bowls. I suspect what you are seeing is actually an accelerator pump on the float bowl of the left carb and what you called a needle is its actuator rod. The set of carbs with the accelerator pump will also have one more tube between the carbs.
The accelerator pump is designed to be operated when you apply more throttle suddenly. It basically squirts a bit of raw fuel into the carb throat to help make more power sooner.

The air cuts are on the left sides of both carb bodies. If you have any doubts about them I recommend bypassing them. This article by Mike Nixon explains why you should bypass the air cuts anyway and how to do it
 

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Discussion Starter #7
I wonder if plugging those holes will help with the popping. When I pull the choke slightly the popping goes away above 2000rpm on deceleration. Running a bit on the lean side. Also I wonder if I should up my jets a bit more. Have 90/120 in it now. I haven’t been able to get it to run more rich. Does accelerate really nice with no hesitation.
 

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Here’s the results of the spray test. Slight rise in rpm at the carb to rubber left side. When I spray at the intake gasket to header, I can choke it out with the spray. All good on the other side. View attachment 200947
Somehow I didn't catch that the first time. If spraying something flammable in that area makes any difference you should definitely deal with that leak before doing anything else. Make sure that the crush washer under the screw is sealing properly and that the o-ring is not damaged and hasn't flattened out (replace them if you didn't already).
 

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Discussion Starter #9
Fixed the leak. Oring had a chunk missing. Grab one from my doner bike. All good now.
 

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Discussion Starter #12
The person that had the bike before me had swapped out the insulators not long ago. It looked new and wasn’t flattened
 

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Discussion Starter #13
Going for a ride?
Yes took it for a ride. Before I got it the bike sat garaged for about 5 years. Put about 100 miles on it over the past few days. Doesn’t smoke much anymore on a cold start.
 

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Yes took it for a ride. Before I got it the bike sat garaged for about 5 years. Put about 100 miles on it over the past few days. Doesn’t smoke much anymore on a cold start.
Did the replacement get rid of the "popping"? I inquired about "popping" right after my first ride of the season. I have a new to me GL650 that has all the vitals redone is is extremely smooth, so it was a contrast. But it was gone the next day.
 

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Discussion Starter #15
Still pops on deceleration.
 

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Does spraying something flammable near the intake manifold still have any effect? If so keep working on that area. If not look to the other suggestions.

BTW: As I told Lee a week or so ago, popping from the exhaust during deceleration (a mild form of afterfire) is usually caused by oxygen from a small air leak allowing unburned fuel to ignite in the exhaust system. It should not happen if everything is working as it should but it rarely does anything more than annoy people because they know something on the vehicle isn't working perfectly.
 

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Discussion Starter #17
Seal has been replaced, no more intake leaks that I can find. When I pull the choke slightly the popping goes away but when I come to a stop the idle is too high.
 

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The ACV covers have tiny drillings to transfer vacuum through the area where the O ring under the cover sits. These are tiny and can block having the same effect as defeating the ACV - they don't work.

Might be worth a look and a spray through with carb cleaner to check.
 

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