89 Sporty Sputtering Help Please (Video Inside)

[Tattooo]

Changed the plugs , added some sea foam in the tank (did wonders for my old ford)... seems to be running smoother now, still gonna add a fuel filter and give the carb a clean... cheers

Glad it's running better...... The plugs looked a little fouled to me....... And since it's your ole lady I figured she had been riding it easy and it's been loading up......

[farmall]

The tiny cute inlines better suited to lawn mowers are a restriction and the glass bodied car filter aftermarket junk are restrictions that beg for leaks. Their problem is small holes and often the length since there's little room for a straight filter without kinking the fuel hose. Most are designed for 1/4" hose which makes their inlet and outlet holes much smaller in diameter.

The inlines that don't restrict are 90-degree plastic 8mm (5/16") "Toyota style" (from when 'Yotas had carbs) auto filters. I've run them since the '80s (they were popular when Harleys were still considered transportation instead of art bikes) but don't care how they look. They stop far more trash than petcock screens and last indefinitely.

It gets obnoxiously hot in SC but I've never had vapor lock or insufficient feed.Customers have which I corrected. IMO while old cars with diaphragm suction fuel pumps could of course vapor lock (heated fuel expands halting flow a suction pump cannot restart) because suction is feeble compared to pressure from an in-tank pump what happens with too small a filter on a gravity system is restriction prevents refill of filters fast enough to keep up with carb demand. Imagine trying to breath through a straw while running...

Jap bikes with dual tiny inline filters don't have that problem because two lines feed much more fuel than one. I've installed many on rice rockets with rusty tanks and cheap customers.

On HDs we used to wrap the fuel hose in a piece of beer can where it passes between cylinders to drop temps and reduce chafing. Modern fire sleeve or wrap is tidier but either reduces heat to the fuel line.

[Skjoll]

When it comes to fuel filters I definitely go against the grain because I use them and have for decades. I prefer the glass ones with the replaceable nylon(?) mesh filters (safety wire a protective sleeve of rubber tubing for the glass body leaving 1/4 of the filter exposed for viewing fuel flow) but have used large and small disposable filters with paper elements. The pressed bronze/brass bead type elements are the ones I stay away from because they don't seem to flow too well due to the element's small surface area and the nooks and crannies clog easily. Before installing a filter I will flow test it and most will usually flow 1 gallon of fuel in less than 3 minutes, more than any of my bikes could consume and if the filter flows dramatically less then I don't use it. Also, when routed properly there is no danger of vapor lock. I lived in Georgia for 17 years and rode all over the south, raced on tracks throughout the south during brutally hot summers with ambient track temps over 105°F yet never had vapor lock issues even during painfully long delays at the starting line or when stuck in gridlock traffic.

...On HDs we used to wrap the fuel hose in a piece of beer can where it passes between cylinders to drop temps and reduce chafing. Modern fire sleeve or wrap is tidier but either reduces heat to the fuel line.

I use a length of exhaust pipe wrap (because I still have a bunch of it), fold it lengthwise, sew the long edges together to form a sleeve and run the fuel line through it.

[ProfessorSquidbeard]

sounds like mine did when it had a big ole intake leak.

[Tattooo]

sounds like mine did when it had a big ole intake leak.

Yea that was my first thought too....... That's why I wanted to see the plugs.............

[metalheart28]

When it comes to fuel filters I definitely go against the grain because I use them and have for decades. I prefer the glass ones with the replaceable nylon(?) mesh filters (safety wire a protective sleeve of rubber tubing for the glass body leaving 1/4 of the filter exposed for viewing fuel flow) but have used large and small disposable filters with paper elements. The pressed bronze/brass bead type elements are the ones I stay away from because they don't seem to flow too well due to the element's small surface area and the nooks and crannies clog easily. Before installing a filter I will flow test it and most will usually flow 1 gallon of fuel in less than 3 minutes, more than any of my bikes could consume and if the filter flows dramatically less then I don't use it. Also, when routed properly there is no danger of vapor lock. I lived in Georgia for 17 years and rode all over the south, raced on tracks throughout the south during brutally hot summers with ambient track temps over 105°F yet never had vapor lock issues even during painfully long delays at the starting line or when stuck in gridlock traffic.




I use a length of exhaust pipe wrap (because I still have a bunch of it), fold it lengthwise, sew the long edges together to form a sleeve and run the fuel line through it.

I like your Idea of sewing the wrap together! I'm gonna use it next time I change my filter.