No such thing with me.
But I've been thinking..since the two gallon fillup is more or less the exact
capacity of the right tank..and filling it up cures the probs..it might be
possible the left tank is blocked by a wrong position of the gas switch.
I have it in the ON position..but maybe I should set it to reserve to get gas
flowing properly?
I just don't know ( yet ) since I'm still learning about the bike.
Can anyone shine some light on that?

 

you may have stumbled on to a clue.
if the lower part of the petcock screen is clogged, switching to reserve may show this because reserve feeds from the lower part of the petcock. the normal position feeds from a tube that sticks up higher.
it would be easy to pull the petcock and clean the screen. you either fix the problem or rule it out as a possibility.

keep in mind, it doesn't empty one tank and then go to the other. they both equalize as the fuel level is dropping.

 

The only way you can drain one tank without draining the other is if the crossover tube is clogged. In that case you will drain the left hand tank and not the right hand one. The problem is most likely on the drain side of the right side tank.

As for being new to harleys don't worry about it. I have only owned mine for 2 years and am learning all the time. The best mod I have done is take out the stock cam and install an EV-27 cam. it did wonders for the performance.

 

Quote : keep in mind, it doesn't empty one tank and then go to the other. they both equalize as the fuel level is dropping.

Good info...this double tank is very confusing with two go juice outlets.
So..after all..it's the same as the rest of the world.
One valve controlling the flow..right?
Then what's the point in having two gas outlets?
I just don't get it.

 

you should have only one gas outlet (petcock), on the left side. the gas flows from the right tank into the left tank via the crossover hose at the front of the tanks. both the right and left empty at the same time. the petcock has a short tube sticking up, inside the tank. it normally feeds gas thru this tube. when the fuel level drops below the top of this tube you can switch to reserve, which feeds from the lower portion of the petcock.

drain the tank, pull the petcock, clean the pickup screen, and it will become obvious to you how it works. even if cleaning the screen doesn't resolve your problem, its good maintenance.

 

Well, just got back from out of state and took my bike for an immediate ride. 12 miles in, same problem. I've kind of ruled my problem to when I take off quickly from a stop. Hit the gas, run through a couple hears quickly, then spit and sputters. Did it twice to me. Im bringing it in to a nearby old school stop here in Denver, not a dealer. It sucks but I just dont have the time or Evo knowledge to get this worked out. I tried removing the gas cap while it was doing it and it did not improve at all, also checked my vent line and did not find any kinks. Im guessing my is fuel delivery but Im not really sure. Both times it ran like crap for a mile or so then snapped out of it.

 

Check you haven't got a chafed wire between the ign pick up and the module.....happens a fair bit on older bikes.

 

i agree with johnnyc. is sounds to me like a problem i had with a guys bike i did some work on. he had put aftermarket caps on it but he didn't buy a vented one so it built up a vaccuum in the tank after driving a while and would starve the engine.

also, i worked on a metric for a guy once. needless to say i took apart, cleaned and re assembled and installed the carb about 5 times. couldnt figure out for the life of me what was going on. was doing the same thing yours is except all the time. turned out it was the sea foam he had put in the gas a few days earlier. i have no idea why it ran like it did but as soon as i drained the tank washed it out and put fresh gas in it, it smoothed out. never had a problem again. not sure if this helps, but just my 2 cents....

 

I had it again yesterday..this time when passing some trucks with 75 mph.
Hesitating..slowing down..no more throttle response..coughing few times.
Don't really know how I managed to stop the bike on the roadside.
One last big cough and stone dead.
Waiting for couple minutes..cranck it up..good idle..off I go.
Was thinking about seafoam if that does'nt work..new ****.
If that does'nt work another carb..if that does'nt work maybe another bike..ha.ha..
Seriously folks..this thing is getting dangerous..must find a cure.
And it seems I'm not the only one.

 

if you run it hard, and then it starts spitting and coughing, it may not be refilling the carb bowl fast enough to keep up.

AGAIN - clean the petcock screen.

drop the float bowl and check for debris. clean it out and check float level adjustment.
after all this time, if you still haven't checked the petcock screen you are wasting our time.