One petcock feeding two BS38's

[5twins]

I gave up on the clear plastic lines years ago. They shrink and get hard as a rock from the heat. Look cool though, lol.

 

[xjwmx]

You dont think it will get hard to fast.

Nah. I used two different types of clear, one kind that was really transparent, like water, and another kind that was more translucent, like wax paper. The first kind got hard pretty quick but the second kind stayed flexible. But either one would work fine. I usually replace it all when I change my gas filter every year, anyway because it's so cheap and easy to get. Instead of a clamp I just put a little zip tie around it. Home Depot has a black kind of zip tie that they call UV resistant on the package, but any kind would probably last at least a year. Most people here that I know of use clear line of some kind or another. gggGary thinks black sheds particles inside.

 

[xsfreak]

you could also use tygon. its made for fuel also its translucent yellow

 

[xjwmx]

^They have something that looks like that at the auto parts stores but only in the smaller size; 3/16? I would use it just out of curiosity, if it was 1/4". Not into it enough to special order

 

[jayel]

actual yamaha line was 7 mm hard to find, use the 1/4" yellow tygon it will stay flexible get it at a lawn mower shop.... I cut a small section about 5/16ths long and slide it over the hose end it acts like a clamp no leaks but you can pull the hose off the barb if needed

 

[DogBunny]

x2 on Tygon.

 

[xjwmx]

If that sheeit don't leak it works for me.

 

[timbeck]

Tygon is the best--- tim

 

[dirtymike]

Well i sure wished would have checked the forum before i picked this clear. Glad it wasn't but 6 bucks. Where do you get the Tygon at. Here is a pic of the stuff i got. It leaves plenty of room for a straight run to the tank, almost vertical. Thanks Dirty

 

[xjwmx]

Well i sure wished would have checked the forum before i picked this clear. Glad it wasn't but 6 bucks.

What you have is exactly what I have and it will all be fine. One unfortunate thing about all of the xs650 sites is how influential some anal retentive authorities are...

 

[dirtymike]

Ive caught on to that, vendors run the site or pay most of the bill. But its always nice to have more than one insight. Thanks Dirty

 

[xjwmx]

Well, I was a little harsh as is my bad habit. It would have been better like this:

Well i sure wished would have checked the forum before i picked this clear. Glad it wasn't but 6 bucks.

How come? Rather spend 12 bucks instead?

 

[5twins]

He will be spending 12, then 18, then 24, etc. as he replaces it every year, lol.

 

[xjwmx]

Personally I think of it as a $6 yearly inspection fee of the whole fuel system vs the cost of a tow truck. But I do think it would probably last longer than a year...

 

[jayel]

one thing I have noticed is your carb atmospheric vents are tied together... no big deal except that long hose (red) the regular hoses (two) are usually only about 4 / 5 inches long to small brackets on the float bowl screws, a long hose can screw up the carb breathing properly, I put long hoses on my vents once and it ran like crap until I shortened them

 

[gggGary]

I think know really old rubber lines shed from the inside. Fuel and brake. I think tygon comes in solid colors like gray maybe black too? I got some egay tygon that is not much good, ethanol swells it. (a bunch). I bought some of the blue Tygon fuel line, that seems to be working fine even with ethanol. So the other may have been counterfeit tygon??? I like these "Mikalor wire spring clips" fuel line clamps they are easy on off and hold very well.

While working on madness I had those clamps off and on dozens of times. No problem

 

[DogBunny]

There are perhaps a dozen different types of yellow Tygon, each with a different coefficient of ethanol-induced swelling, but all are pretty low. I buy the cheapest yellow Tygon on eBay. Yes, it swells a little, so I put a small tie wrap at each connection, and I am very happy. It lasts forever, stays flexible, and it is transparent which is very useful.
Will have to look into blue Tygon...

one thing I have noticed is your carb atmospheric vents are tied together... no big deal except that long hose (red) the regular hoses (two) are usually only about 4 / 5 inches long to small brackets on the float bowl screws, a long hose can screw up the carb breathing properly, I put long hoses on my vents once and it ran like crap until I shortened them

Interesting observation. I always thought that the purpose of the downward-pointed vent tubes was merely to keep dust and dirt out of the system, and I have always just eliminated them. But, yes, a few inches of tube are also going to create some resistance. Maybe this is an engineered-in resistance? I think some comparative testing, with and without the original vent tube set-up is in order...

 

[dirtymike]

Ill use this till i see deterioration and go to the tygon. Want to make sure i get the real Tygon. Did some research and it seems to be some pretty tough stuff. I didn't know what the two lines were when i got the bike. They were hard and cracked. Thought it was over flow and plumed it downward so it hit the ground instead of the bike. Haven't had any issues yet with them being long. Ill divide them and make them short(4to5")to see if i have any change. Looking for some jets now. Running pods and open headers seem to loose pulling power at higher RPM's. I'v read here to use 127 for the main jet and 27.5 for the pilot. Seems that all the 650 sites are out. Thanks Dirty

 

[jayel]

Ill use this till i see deterioration and go to the tygon. Want to make sure i get the real Tygon. Did some research and it seems to be some pretty tough stuff. I didn't know what the two lines were when i got the bike. They were hard and cracked. Thought it was over flow and plumed it downward so it hit the ground instead of the bike. Haven't had any issues yet with them being long. Ill divide them and make them short(4to5")to see if i have any change. Looking for some jets now. Running pods and open headers seem to loose pulling power at higher RPM's. I'v read here to use 127 for the main jet and 27.5 for the pilot. Seems that all the 650 sites are out. Thanks Dirty

Yes, I used long small tubing (3/16ths?) your tubing may be large enough to allow the fuel level to be at normal atmos. pressure instead of trying to draw the fuel level against a vacuum like mine did

 

[5twins]

Your '77 carbs may require mains in the low 130s for your mods. These are just common small round Mikuni main jets, available just about anywhere. No need to buy them special from a 650 place. Most of us prefer to use the genuine Mikuni jets as well, not the knock-offs.