Fuel System Refresh

The fuel lines looked original or at least very old.

  My experience with the cloth covered fuel lines is that the outside can look ok but the rubber hose is actual cracked. Plus the fuel filters were looking a little done.

 This was proven when I pulled the lines.

 There is a lot of lines on one of these bikes. Especially since the rear carb is at the rear of the engine.

I like to use Tygon fuel lines. Sure it's bright yellow, but it's translucent so you can see the fuel. Also Tygon stays flexible despite the crap they call gas these days. I've had Tygon fuel lines on one of my Bultacos for probably 7 years and it's still good. That's not bad. I buy it at a lawnmower parts store for $.19/in, for the Cagiva I bought 50 inches thinking I'd have a bit leftover for spares. But in the end I only had about 8 inches left.

Here's how I routed the back carb. It's similar to how the "museum bike" (see earlier post) was routed, at least the part I could see. The line on my bike originally came outside the frame rail and then over the intake manifold to the carb. I didn't like this so I came around the back of the carb. I tucked the line under the fuel line to keep it away from the back cylinder. I also tied it off so it didn't rub on the K&N filter. A very long route for sure.

View from above with the fuel line entering from below the carb. 

Route around the air filter. 

Here's the filters I used. Apparently made for NAPA by Wix. They are for both 1/4 and 5/16 lines. I cut off the 1/4 parts to shorten them up. Although the Tygon is 1/4in ID you shove it onto the 5/16 parts and they don't come loose.

Here's the routing for the front carb. A lot simpler. Plus the crossover. There doesn't appear to be any reserve on the taps so I'm curious what people do, just wait for the light on the dash?

With the lines on I turned on the taps and... nothing. With the clear filters and lines I only see a dribble. Ok, so I knew the old filters were a bit gunky so I suspected clogged filters at the taps.

So off the tank came. Just the two bolts at the back of the tank and disconnect all the fittings. Pretty neat.

The tank opening was completely clogged. I dug out the bad stuff and then flushed it some more with the gas remaining in the tank.

Not a great picture but the tap was completely full of rust and debris. There aren't any filters on the taps which mean I don't think on a stock bike there are any filters at all. I cleaned the taps throughly and reassembled. I have the bike back on the battery charger as it drained while it was just sitting there. Needless to say a new battery is also on the shopping list. At least the fuel system is a little better. I'll have to deal with the rusty tank at some point. I'll keep an eye on the filters to monitor it's status.