removing octy

[DGXSER]

I believe the routing that 81XSProject was suggesting is to cap/plug/tie together the PRIME outlets, they no longer feed fuel to the carbs.

Then take one line from each sides ON outlet to a T in the middle of the bike and run the third outlet of that T to one single fuel filter. Take the outlet of that filter to another T fitting. Take the other two outlets of that T to each of the fuel feeds to the carbs. This way both petcocks feed the engine, but if one gets buggered up, you CAN run on one only if needed.

[John]

Hi Phil,
Yeah, you are not alone in finding that out. Vacuum caps are fine for sealing off vacuum ports but show them some gasolene by just turning to "prime" one single time to check they work and they'll shrivel up and die in a week or so.
After the vacuum caps I'd used to seal off my unused "prime" ports failed in service I shoved on short lengths of fuel hose but you are right, bunging a bolt up 'em looks kinda amateurish. I sealed each of mine by shoving a one size larger ball bearing up them.

I gotta disagree with some of you on this one. I have had the same vacuum caps on the prime ports of my petcocks for a few years now, and I have had no problem with fuel dissolving them. I have selected prime a few times by mistake, with no damage to the caps. It may be the material that your caps are made of that caused them to deteriorate. Running a hose between the prime nipples will work, but that's another line to have to remove when removing the tank, and it is possible for fuel to collect in the hose if the petcock has a slight leak, or prime is selected, and it can spill all over when the hose is removed. Running on one petcock is easily accomplished, and there are no fuel starvation problems at high speed. I ran this way for years, with no problem. You should have both petcocks plumbed in, and you can just select the other petcock when you detect you're running out of fuel on one side. I used the left petcock as my primary side and would switch to the right when the time came, as that way I still had use of the fuel light.

[gk45241]

Petcock

Ok so If I have this correctly. Pluging the prime on both percocks is good and not an issue. Then by running the right feed to the left and the down to split and connect with both sets of carbs i would be able to toggle just one petcock for MOST normal use.

What was the situation with the fuel light? which side of the tank does the low fuel light read from? Will it still come on and key you to get fuel (ir idiot light) or to turn on second petcock?

Gary

[John]

I made a mistake in my last post concerning the petcocks. It should have said I run on the right side petcock, and then switch to the left.
The fuel sender is on the right side, so when the light comes on, just open the left side petcock, and leave the right side open as well. This will allow the fuel to balance out on both sides of the tank, as liquid will seek it's own level. You don't need prime because fuel will flow with the petcock in run or reserve.

[DGXSER]

Ok so If I have this correctly. Pluging the prime on both percocks is good and not an issue. Then by running the right feed to the left and the down to split and connect with both sets of carbs i would be able to toggle just one petcock for MOST normal use.

Try this diagram if it comes in legible

What was the situation with the fuel light? which side of the tank does the low fuel light read from? Will it still come on and key you to get fuel (ir idiot light) or to turn on second petcock?

Fuel light sending unit (my term anyway) is in the right side of the tank. It will read when that side is low. I feel that on the specials at least the back end of the tank is low enough that fuel is still being distributed between sides when the fuel light comes on. JMHO. Yep, it would still light, especially if you run the right side petcock normally.

Don

[81xsproject]

For anyone worried about using just the right vs. just the left and the FUEL light; it doesn't matter. The reserve/main fuel separation height on the filters is near equal to the fuel level that triggers the fuel light. I run on just the left petcock, and typically the fuel light comes on 1-5 minutes before the bike will start to stutter and I have the reach down and switch to reserve. This I also do with JUST my left petcock, also. This way, I have TWO reserve tanks.

[fredintoon]

getting the last spoonfuls

Ok so If I have this correctly. Plugging the prime on both petcocks is good and not an issue. Then by running the right feed to the left and then down to split and connect with both sets of carbs i would be able to toggle just one petcock for MOST normal use.
What was the situation with the fuel light? which side of the tank does the low fuel light read from? Will it still come on and key you to get fuel (if idiot light) or to turn on second petcock?
Gary

Hi Gary,
if you note how fast the fuel comes out of one petcock when you drain the tank, if the bike drank fuel that fast it'd be getting about 3 mpg. I'd say that one petcock will serve, no matter what. When I had my Special tank plumbed in an H-pattern I habitually ran on just one tap just fine.
The Special's thermistor style tank sender is on the right side of the tank. The Standard's float & rheostatstyle tank sender is on the left side of the tank.
The rear of the tank tunnel on either model bike is barely an inch above the bottom of the tank so the red light should be on or the gauge should read Empty way before switching the other tap on gives you those last few spoonfuls of gas.

[fredintoon]

For anyone worried about using just the right vs. just the left and the FUEL light; it doesn't matter. The reserve/main fuel separation height on the filters is near equal to the fuel level that triggers the fuel light. I run on just the left petcock, and typically the fuel light comes on 1-5 minutes before the bike will start to stutter and I have the reach down and switch to reserve. This I also do with JUST my left petcock, also. This way, I have TWO reserve tanks.

Hi 81XS,
to go further between fill-ups I use a Standard tank on my Special. This means installing the Special's thermistor sender in the Standard tank. The Standard tank's sender cut out is identical to the Special's but it's on the other side of the tank. So you mount the thermistor with it's wires pointing forwards or it'll be upside down and only turn the red light on when the reserve has been switched to long ago and you are perhaps 100 yards from totally empty. Done properly the red light comes on just when you have to switch to reserve. The Standard tank reserve is about one gallon so I have ~25 miles until the tank is dry. I don't have the single tap option with my Standard tank fuel hook-up. The leftside tap serves the two rightside carbs & vice-versa to let the in-line fuel filters fit easier. So I only have the one warning. My second reserve is a 2 gallon jerrycan in a special rack on the sidecar.

[81xsproject]

I have a standard tank and am planning a swap after I paint. On the subject of one-petcock-fuel-starvation. It is possible to starve the bike but you have to REALLY be trying. I was able to accomplish it doing 0-100 1/4 mile practice. Even then, however, the bike was just starting to starve. The issue only came up while running on one petcock. So, the long and the short of it is that unless you're at the track or riding that way, one is more than sufficient.

[gk45241]

Pods

[QUOTE=renegade_xs11g;198955]The tank has the reserve,

You want to clean up the look, I'll bet you've put on pod filters, right?


NO pod filters yet but i sense your sarcasim.. Probably will due to the ease of removing the carbs for cleaning and the abilty to have some room to work around the engine. Also because the stock airbox is a royal pain in the ass. I am not the purest that some are on this site so Not all of the stock parts are there( or came with the bike) for that matter. ALthough I love and appreciate the pure look of the bike, I am starting from a slightly less than perfect place to rebuild the perfect retro. Gonna end up being more of a bobber style.

Thanks for clarifying on runnng the lines.

Gary

[gk45241]

Diagram

Thanks for the input guys. Just read the other opinions on the routings. And saw the diagram.

Gary

[DGXSER]

No problem Gary! Sorry we did not get to discussing it last night, I know you started down that path but my pea brain was focused on the rear brake.

Your gonna have a very cool lookin ride when you get done. If I was starting from where you are, I would not focus on restoring it either. To many pieces missing that are to hard to find, and a mixture of bikes anyway with the standard forks on the special. Your doing a great job with it!

[gk45241]

Love hate relationship with these things already

Thanks appreciate the vote of confidence. With you Doug and so many others wiling to help out It may not look like the classics but damn she should scream.

Gary

[robert_hollis]

Not to beat a dead horse, but...

I recently took the tank off my 79 Special to clean and repaint it, and I've been thinking about simply replacing the petcocks with aftermarket ones. I don't have an octy, and I'm not trying to keep my bike stock. Any recommendations on simple and reliable petcocks for these bikes? Preferably something under $50.

Thanks,

-Rob

[renegade_xs11g]

NO pod filters yet but i sense your sarcasim..

No sarcasm here, I just kinda figured that with you wanting to clean up the look, you had, or are going to, put pods on....

You can't really see the fuel lines with an air-box....

One thing with pods, make sure you get the ones that don't restrict air flow, if ou get the wrong one's you'll lose the top-endDAHIK