[DaveFxst]

I could use some suggestions. I have a carbureted 2001 Softtail, 22,000 miles, has never missed a lick. Rode a couple hundred miles yesterday, bike worked flawlessly. Pulled into a gas station, filled up, lit her up and completely lost the idle. Sounded like it was running on one cylinder briefly, had to keep it cranked up all the way home, popping and backfiring. Checked all the usual suspects, ie battery cables, plug connections, etc. Started it, had same symptoms.

I have the factory manual and will get into it this weekend. I was just hoping to get a place to start if someone else had the same problems. Any help appreciated. Thanks in advance.

[duke76]

Sounds very much like a vacuum leak, does it run a little better with the choke on, spray ether or wd 40 or run a hose from your propane torch around the fittings between the carb and intake and head and if the motor speeds up you found your leak, I would almost guarantee that is your problem. Todd

[hotroadking]

Unless you got something in the fuel like water or crap sounds like it might be a coil or breaker

It actually sounds more like an ignition module, if you had an intake leak that would manifest itself over time, this sounds like it just "happened"



Check the fuel line see that it flows properly and clean out the carb, clean the jets out with some pressurized air, you can get a can of compressed air at any store for cleaning computers etc.

If that isn't it you eliminate fuel

The intake leak check with wd-40 or carb cleaner is good. Not sure about propane but that's your call

I would check the plugs, wires and coil to see that they really are firing.

Look for a loose ground wire on the battery, check all connections.

[HarleysLR]

did you let the ECM light go out, you know the little engine light in the speedometer. I fired mine up once without letting this light go out and it sounds like the same thing you are talking about.

[Lucifer]

Sounds like you got a tankful of crap for gas. try draining the tank and put fresh fuel in..if it's still acting up, check out what the guy's above said.

[DaveFxst]

First of all thanks a ton for the ideas. I love this forum.

It did indeed just happen, no warning at all. This was a whole lot more abrupt than a developing condition. I was considering the fuel idea, but the tank was half-full when I went into the station. It is a high-volume station, which is why I go there. I've read threads here before about bad gas when the station is an out of the way location that buys spot market gas.

The ecm light was out when I hit the button - made that a habit years ago, though I'm sure I miss it sometimes. Anyway, when I restarted it at home, it did the identical thing.

I will take each suggestion, one at a time. I will start with the vacuum test using WD 40. If that doesn't work, I will pull and check the plugs and wires, et al. I will also clean the gas filter and check for fuel flow.

I am not sure how I would check the functioning of the ignition module - would that not cause an error code on the speedo? Ditto the coil, DO they go out that fast?

Again, thanks for all the help. Will keep you posted.

[duke76]

Another thing I just thought of, I had a guy fill up his 4 wheeler with E 85, did about the same thing would barely run, there is a lot of stations that have this now, not saying that is what you did but a possibility, also somethimes vacuum leaks dont happen over time, a cough sputter or backfire can blow a seal immediatley normally when a bike has a vacuum leak it will run better with the choke on as it is adjusting the abnormally lean condition, Todd

[DaveFxst]

Got time to check a few things last night. Fuel on, enrichener out, 10 seconds of starter, nothing. Turned the throttle a quarter turn, it lit up really ragged. Died as soon as throttle rolled off. Indicates I have a)fuel and
b)spark. Duke76, I am pretty much covinced the vacuum leak is the culprit. It did backpop when I fired it up at the gas station, which may very well have blown a seal.

Will do the WD40 test this weekend, pull it down and see if I can find the little b#$tard.

[hotroadking]

Turn off the fuel,

Remove the air cleaner and backing plate

Remove the float bowl, clean out with compressed air and clean out the pilot and main jet.

Sounds to me like a blocked pilot, won't run at idle so it's not getting fuel down low but crank open the throttle and the main jet comes on and it runs,

As to the ignition it should set a code, however had an ultra that was doing that, very similar, would run just fine then blam, pop pow

Checked everything and the guy said it did it in the rain more than dry....

So fired it up and started hitting the bike with a water hose, easy, down low and worked up, when the water hit the front wire it arc'd to the motor.
POP BAM POW!
Turned it off and really checked the wire, what felt fine wasn't it had cracked and when water got to it went nuts.

Never set a code.

[DaveFxst]

Resolved the problem on Saturday with the WD-40 test. It was indeed an intake manifold leak. Removed air cleaner assembly, replaced the manifold gaskets, took bowl off, cleaned jets, replaced air cleaner gasket, runs like a champ again. Thank God for maintenance manuals. I was surprised how clean the carb was inside, given that it was never opened up in 8 years. Float, springs, etc. look fine.

Since it is now a typical northwest Pennsylvania autumn, ie 29 degrees at night and 60 degrees during the day, I'm adding Stabil to the tank at fillups. I've never had a fuel problem with fall riding or winter storage, and I use the stuff in my heavy tractor as well.

[duke76]

glad you got it going, I thought when you were explaining the problem, that it alsmost had to be a vacuum leak, Todd