1990 F-L. Idle a bit up and down lately, neutral light flickers when stationary, fan speeds up when headlights off. Was also cutting out so I upped the idle speed to about 1400. This stopped the engine cutting out, but still lumpy so I took out the stock air filter and fitted my K&N, which I had cleaned and oiled a few months ago. First time out, cut out again today.
Also strong smell of petrol when I shut the engine down at the end of my commute.

Does this all point to carbs? They were sync'd a month or two ago but as far as I know have never been checked (now over 58,000 miles). Local mechanic says carbs possibly have fuel stuck above the floats. If I'm going to strip the carbs, what parts do I need to buy?

Thanks all.

 

Wow, I just posted the same thing!

Hope you find out what it is, mine is acting the same way to a T. I've been running the K&N since last Summer.

 

You get the strong smell of fuel too?

I forgot to mention that today in the UK it was warmer than usual, not sure if this has anything to do with it?

 

Ah, that's the only thing I'm missing. How's your economy doing? Mine's surprisingly good, think I was 37 mpg last fill up.

How many turn out on your air/fuel idle screws? I think I'm at 2 last I messed w/ them.

 

Could be two problems, the smell of fuel may not be the same problem as running issues. Perhaps lifting the tank and looking for leaks.

I advise everyone to up the jetting to get rid of the factory lean condition. It raises hell now that ethanol is in the fuel. When rejetting spray the carbs out well with carb cleaner and the 'possible' float sticking may also go away.

Up the jetting and it will run cooler. It use to sound like marbles in a blender on take off before I rejetted, now its silky smooth.

 

I get 32mpg. Heavy London traffic and I don't ride soft.
I wish I knew what rejetting was and I've no clue about idle screws. It's me who's idle! I've never looked at a carburettor in my life. May have to now! Can't be harder than replacing the starter clutch and CCT... can it?

 

32 is a bit closer to my norm, that 37 had some highway miles on it.
The carbs are easy, just keep track of the little parts. Hopefully they just need a little blow-out with carb spray.

 

Cleaning the carbs is simple enough, but do them one at a time so you don't interchange the parts and cleanliness is next to Godliness!

 

Leaky T's and no not the Tetley type , the fuel T orings , while you are at it clean the
screens above the float valves and check and make sure the fuel bowls are sealing tight.

also inspect the tank mount up near the triple where the two bolt fasten it down.

That mount stresses and cracks leaking fuel back down the inside of the tank too.

Pull your jets and in particular the idle jets , with the pilots all the side holes need to be
clean and looking into the end of the pilot a microscopic hole should be visible at the
opposite end - clean the pilot jet needes with a soft cloth and spirits or parraffin etc.
Memorize how the spring then washer then oring goes on each air needle in that order.
If the pilot jet needle orings have shrunk replace them too as they'll leak air past the
needle exhibiting erratic idle.

Air needles are set this way
gently screw all the way in to a gentle stop
Back out 2 +1/2 full turns

When you pull the carbs it pays to do it all

Hope this helps ....last thing .....if you separate the carbs to do the Fuel T orings
watch for "flying tension springs" do not loose them they're an absolute necessity
and a pain in the neck to find when they fly