What have I done????

[Toolmaker Tim]

Got the bike out to ride in to work this morning. Pulled the bike out of the garage, gave it 1/2 choke, and it started right up. Pulled on the sweatshirt and wind breaker and grabbed the helmet. By this time the RPM's have gone up and it's time the push the choke in. I turn around and the #1 cylinder pipe is glowing bright orange right at the bend. It is the color that you look for in oil harding steel right before you drop it in the oil bath. I shut the bike down and tried not to think too much about it till I got home. I haven't pulled the plugs yet, but my first guess is a carb problem, the second is a bad header gasket. The only thing I've changed is the fuel lines. I had the two lines off the petcock going into a tee and then going to the pair of carbs opposite the petcock. I now have only one line off the petcock to the carbs. I have understood that the front petcock nipple is for the vacuum to open the petcock to let fuel into the carbs. Was I right the first time with the lines routed to tee? One other thing. I ran a fuel line between the two vacuum connections thinking that would prevent a fuel leak. Maybe that was a BAD idea and one petcock is closing off the other and the other bank of carbs fuel supply. I'd like to get it right so my winter projects for the bike don't include an engine rebuild Any and all ideas are appreciated. Thanks in advance.

[bikerphil]

Re: What have I done????

[QUOTE][ I have understood that the front petcock nipple is for the vacuum

This applies to Standard petcocks only. You have a Special?

[Toolmaker Tim]

Yes, at least the tank is. I am starting to find some XJ parts the deeper I dig. LOL

[bikerphil]

petcocks

With Special petcocks, cap off the forward ones when not using the octopus. The Standard petcocks are a totally different animal and won't bolt up to a special tank. Special petcocks have no vacuum line.

[Toolmaker Tim]

That's what I have. The bike was a basket case when I got it. Now the owner is becoming one

[Toolmaker Tim]

The Special petcocks that is.

[bikerphil]

fuel lines

Okay, after capping off the front fuel outlets, run line from left petcock to right carbs 3+4. Run line from right petcock to left carbs 1+2. should be good to go. Cap all 4 carb boot vac. ports. I recommend using inline fuel filters but thats up to you. HTH

[Toolmaker Tim]

Ok. Inlet ports are blocked, got inline filters, righthand petcock goes to the left pair of carbs and the left goes to the right pair of carbs. Disconnect the jumper I put between the vacuum connections on the petcocks and plug them so they are seperate. Start it up and hope like heck I haven't wrecked the top end.

[bikerphil]

front petcocks outlets

Just to clarify better... the Special petcocks use no vacuum. The front outlets are for the prime position when using the octopus. If octopus has been eliminated, there is no need for the prime position anymore. On the fuel selector, off, on, and reserve will work normally. Turn petcocks to off position for parking the bike overnight. Also might want to check your oil for possible fuel contamination.

[Toolmaker Tim]

Thank you

Just went out and disconnected the jumper I had between the prime outlets and plugged them off with a couple of 5/16 SHCS. Started it up on 1/2 choke and let it warm up. As soon as the rev's rose the header pipe started glowing. I pushed the choke in and the glow went away. I guess I haven't noticed it before and all it took was it happening at 5:20am with it getting dark and I finally noticed it. My next question is has anybody else noticed this? Do I have a problem in my choke circuit? Things haven't been going very well for me and mine lately, and getting out on the bike, even if it's to work and home, has been helpful. In perspective they aren't serious issues compared to other peoples diffculties, so I can't complain. When they pile on it gets hard to take and a ride sure helps!

[ridinghard]

I'm starting mine up at 4:30 a.m tomorrow to head to work. I'll check to see if I can see mine glowing too. Since it will be 40 degrees outside it may not be able to get hot enough to glow, but I'll keep an eye out and see what mine does.

[Toolmaker Tim]

Outside Temp

It was 53 degrees this morning. I think the header pipes make their own weather. I will be interested to hear what you find out.

[trbig]

I notice that you're using a Jardine pipe. I am going to assume that this is just s single walled pipe. If this is true, then I would imagine it would glow in low light conditions. It would have to get that hot to make the chrome blue on the MAC and JArdines like it does. Imagine how hot it gets when it is bluing/yellowing a double walled stock pipe! Check your plugs though to make sure you aren't running lean. You shouldn't have one getting hotter than the rest.

Tod

[oldyam80sg]

My friend played around with his carbs and idle screws on his XS400.The pipes glowed bright orange and then the bike died.I wouldn't run it like that until you find out what is happening.My SG has never got that hot!And i rode it to work today because the Jeep was getting a few things done to it.Weather was perfect.

[planedick]

Could be

Maybe the synch isn't right and #1 is working harder than the rest.