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`94 FXDS has an Issue, Your Help; Appreciated

Your carb is icing up sit for a fem mins and bike runs ok because the heat rose from the engine and melted the ice blocking the idle and transfer ports
The backfiring and stuttering is caused by the idle and transfer ports being blocked causing a very weak mixture
As the air is drawn through the carburettor the shape of the throat compresses the air this causes the air to chill vaporisation of the fuel coming from the ports causes further chilling of the air cold enough that the moisture in the air will freeze causing ice to form on the fuel ports in the carburettor main is kept partially clear of ice due to the action of the slide needle
Ambient air temperature is not really of consideration at this point however I have not seen it happen more than once over 18 degrees centigrade ( 64.5 degrease Fahrenheit)
As this is a common occurrence here in Uk more especially here in Scotland due to a wet climate I replaced the carb on my softail with a mikuni hsr 42 it now works much better during the course of time I came to realise the wife was having the same issue on her dyna in mid summer replaced her carb also problem gone
In cold weather I would get less than a mile before icing occurred but in warmer weather about 5 or 6 miles once the engine is fully warmed up 10 miles + there is sufficient heat being generated by the engine to keep the carb clear of ice

Brian
 
i also had this icing up problem on my 92 fatboy with standard cv carb but only in frosty weather-would be quite embarrassing sitting in traffic at the lights after only 4 miles having to keep the revs up by fanning the throttle till the lights went green! Only ever happened in winter and after about 15 miles ,prob disappeared,doesnt happen on my 95 nostalgia with mikuni hsr 42,cheers
Nick
 
I`m fairly certain the problem is solved. Joel nailed it, all I had to do was loosen the gas cap. I rode it a few miles this morning and it was all good, after work I`ll put some more miles on it just to be sure.

I can`t thank everyone enough for all your help. If your ever in Santa Barbara hit me up, the beer is on me!
Rod Walsh
 
It`s back! I have had it happen three times last week. The last two times I didn`t even stop, I pulled the clutch in. , turn the key to off, turned the key back on, released the clutch and rode on. It`s not too big of an inconvenience, much better than it was. What bothers me the most is that I believe what`s causing the problem is something simple and I don`t know what it is..
I`ll continue to post here when I have any new information. to share.
 
I have a '92 Dyna. I had to replace the stock ignition switch because it sometimes would not start. It would turn over, but not fire. If I turned the key off and back on, it would start. I guess there was a contact inside the switch that would lose contact.
 
Today the issue went off the rails, it`s worse than ever. I used a bungee cord to tether my phone to my rear view mirror and recorded a couple instances of my problem that I have been trying to describe. The recording is about three minutes long and I know it will tell you more about what`s happening with my bike than I ever could.
youtube URL:
 
To me watching to video almost made me sick, but I can't ride in the back seat either.
It does sound like it is running out of gas.
If replacing the fill cap and making sure ths vent is clear. And the fuel level doesn't make any difference.
If fuel level changes the effect than maybe the hose between the pick up screan and pump has a split in it.
With level close to reserve use a flashlight to look inside, turn ignition to run and look at the hoses for a spray pattern.
I would look in to the tank for anything that may floating that may wrap the pick up screan and restict fuel.
Also see if you can change the pump relay, could be as it gets hot it doesn't allow full 12 volts to the pump.
We use a wire pinch clamp that puts a pin hole into the wire, a way to check for supply voltage after relay to pump. If you were to put this between relay and pump, have the end with the clip exposed so you could connect a volt meter to it when the symptom happens, you would be able to confirm proper voltage to operate the fuel pump. After your done put a dot of silicone on the hole to keep out moisture.
 
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