fuel filters

[tom clisham]

First I dumped the octy

My SG has early carbs. In fact all 3 of my specials do, as 2 are 79s.
I got rid of the octy & really liked the simplicity of the system. Last month i dumped the airbox. It runs better than ever. i ran filters by criss crossing the lines as stated earlier, gives you lots of room. Since dumping the airbox, I ran short fuel lines to nowhere with filters in them to hopefully keep dirt out. This for the carb vent lines.

I've got K&N pods on the barhopper, & did the same thing there.

Now, I pop the carbs on & off just for the heck of it when bored.
My all original 79 SF I wanted that way, for originality. Worked out. It's going to France as I write this. Another happy new XSr. He paid well & got a trouble free bike.

[Aches n Pains]

Fuel Setup

After removing the Octy, this is how I route the fuel lines on my '79 Special.



Left side to carburetors.

"X" fitting so both carbs are fed by both petcocks - brass fitting from ebay (aquarium item)

Inline filter as mentioned in several posts above

Briggs and Stratton shutoff valve so gas can't flow regardless of condition of petcock. Inexpensive though not elegant.

Right side to petcocks

Of course, all joints are clamped with clamps like shown in picture. Note that I just put this together for demonstration purposes. Individual hose pieces need to be cut to fit your preferences.

May not be the prettiest solution but it really works well.

[cywelchjr]

'79 doesn't have octy...it started in '80s... like Bug said, run longer loops down under and back or cross them over(seen it both ways)

All years of the special had the octy, your's may have had it removed before you got it, but it had it from the factory and it shows on the fiche from Yamaha. Just like all years of the standard had vacuum petcocks, as that was a standard feature of ALL Yamaha street bikes during those years.

[jjz28]

Thanks aches n pains, that looks pretty good. I like the x, i never thought of that. I was going to use t's but had to use 2 of them to get it to work so this is much better. Like it.

[Cyclechrist]

Like your x design

Hi there,

Just a thought... by putting an x in there you deleting the (Fuel is low and one side of carbs starving scenario). but are you also creating a fuel dame so to speak?

Have you noticed if the fuel flow changed when running wide open on highway? are you getting enough flow. Fuel Volume,The original had 2 line to 2 carbs giving adamant fuel to both.

It is possible that I'm thinking like a Drag racer!!!!!

I like it though... my try is my self.

[TopCatGr58]

Hey there Cyclechrist,

None of the XS11's had 2 fuel lines to each pair of carbs. The early model carbs have a "T" fitting up high because it's a VENT hose connection. The lower "T" fittings are the only fuel lines, and each line feeds 2 carbs, so the above "X" design feeds the carbs the same as the OEM setup. The other front fitting/spigot on the petcocks are just for the PRIME function for Specials to bypass the Octopus vac. controlled valve, otherwise it only flows from the rear spigot during RUN mode.

BTW, this was a 4 year old post, and so not sure if you'll get a reply from Aches/pains.

T.C.