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So, a year and a half ago. I had my carbs rebuilt, by my regular mech. Yesterday, I start the bike, and there's gas pouring out of the right side carb. I just got the new Bridgstones put on her, I was going to ride to work today. So this weekend, I get to take off the carbs and find the problem, and fix it myself. I'll assume it's a bad float. If so, I'll scavenge one out of my spare carbs.......
 

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Since Larry's not currently on line I'll just chime in here and tell you to also check the float bowl vent tube for splits.



Info courtesy of Larry's book on CX/GL carbs.
 

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I like the rough up and solder method but Larry did learn how to press in a new piece. Took a few try if I remember right.







Here's a cracked one.



 

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I have never seen this particular fault in any carb in Oz. Could this be caused by sub zero temps freezing fuel and expanding it in these tubes?



I've heard of water pipes doing this in colder climates.
 

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So, a year and a half ago. I had my carbs rebuilt, by my regular mech. Yesterday, I start the bike, and there's gas pouring out of the right side carb. I just got the new Bridgstones put on her, I was going to ride to work today. So this weekend, I get to take off the carbs and find the problem, and fix it myself. I'll assume it's a bad float. If so, I'll scavenge one out of my spare carbs.......
are you using an external inline fuel filter,to protect your carbs...........

if not,you could well have tank dirt holding the fvn open.

I'll assume it's a bad float. If so,...that would be my last assumption.

if your fvn does not close properly,then there is nothing left to turn off the fuel.even when your parked up
 

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Has anyone had any issues with the alchohol in the new fuel supply? Lots of rubber parts in the CX carbs and alchohol eats some types of rubber. The new fuel formulation will be 15% so if there is an issue it will get worse.
 

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If you had the fuel turned off for some time, all you probably need to do is tap on the side of the offending carb with a screwdriver handle. After setting for awhile, they sometimes just stick a bit until the floats free up a bit.



I doubt that the tube is cracked, but it is certainly possible. I have had two cracked ones in the last couple of years. I think the reason for this is that big temperature changes stresses the tube and causes it to split. These tubes are extruded, and already have internal stress from that. It doesn't take much more to cause a split. The splitting is very common on exterior brass lamp lamp parts. Most of them over a couple of years old have splits on some of the extruded parts.
 

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From time to time even my Carbs,which are well serviced,may exhibit overflow problems if the bikes have the petccock off and are not run for a while.



1st course of action is as posted to tap the side of the carbs lightly with a small hammer or similar and rev the engine and go for a good run.



Next trick is to place a receptacle under the rear wheel area where the overflow pipes are to catch fuel.

With Petcock closed and using a long necked flat blade screwdriver release the Drain plug/screws at the bottom of the carbs.The left hand side one is easily accessible,you need the long screwdriver for the right hand side one.

If these screws were not serviced and released when the carbs were off you may have to soak them in penetrating oil and leave overnight.

This will allow the floats to fully drop and hopefully the FNVs.Then switch on the petcock and let some fuel run through and out to help clear.

The small brass inserts get a patina on them with stale fuel or lack of use.This can cause them to become sticky.Fuel treatments like Seafoam/RedX or any petrol treatment from the supermarket can help prevent this occurring if the bikes are left for more than a week or so unused.

It's very rare that the actual floats are the problem and the seat of the FNV base can be re-ground using the FNV and Toothpaste but then must be fully flushed with Brake/Carb cleaner.Even after this there may be a bedding in period.



Also click here,



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



 

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You may wanna try turning off your petcock and draining the right carb. This will or should drop the float. Tapping on the carb body when empty won't hurt either, unless you use a very large hammer.....Lol



Then turn the fuel on, this MAY rinse out whatever may be in the needle valve seat that keeps the fuel running after the correct level is reached.

 

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Probably the E10 gasoline. Original Honda gaskets were not made for alcohol. I purchased a set from Randakks and so far so good. Another thing,,,, Add Star Tron additive (Wally World, Boater section). This does not eliminate the water but does keep the water mixed. Just pulled my carbs, after one year for inspection, and they looked good. A lot of people are going to be upset this spring when they go to run their mowers and stuff...
 
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