Yes it vents through the cap - couple screws on the bottom lets you
take it apart - The calif bikes with the extra air can'ster might be
a different animal

after you fill it up just shake bike back and forth a little with the cap off and you can watch it burp a bubble or two from the sides of the tank.

Boofer wrote on 05/09/11 at 21:10:55:

Thanks for the feedback on the cleaning.  

It's an old Savage.  It's an 88 which I bought in 89 when I was living in California.  Road it out in CA for 8 years or so, and put about 25K miles on it.  Never had a single repair on it over that time; just replaced brake pads, filters, tires, etc.  Loved the bike.  Late 90's I went to work overseas, so I put it in my mother's garage. Ended up staying 12 years abroad.  Came back last year and decided to get the bike running as a summer project (job searching, so I had time - no money). Had to replace the petcock (bought used one on Ebay), clean the carburetor (I never spell that right), and redo the front brakes.  It had also developed that famous leaky engine-head plug, so I replaced that, in addition to replacing spark plug, battery, oil, filters, etc.  I know zilch about motorcycle repair, but - lo and behold - it ran.  I was able to get it out on the road in September, and I'm in Minnesota, so I was only able to ride it for a couple of months before it went back in the garage for winter, but it ran really well at first.  Then I noticed that it started intermittently lurching and stalling.  Felt like the engine wasn't getting enough gas, and it would be jerking and die if I let up on the gas.  Then later it would run perfectly.  Before I put it in the garage, I thought that it seemed to happen after filling the tank, but I really didn't have enough time to establish a reliable "when I do A, B happens" relationship.

So I pull it out this spring and start it up, expecting to experience this jerking and stalling, and ... the thing runs perfectly.  I'd filled the tank when I put it in storage, so I'm able to run around town for a couple weeks, putting 100+ miles on it, starting and stopping multiple times, without a problem.  Then Sunday, I pull in to fill it up for the first time, fill the tank to the top, and ride away. I get about half a mile aways and sure enough it starts jerking badly.  At stop signs, I'd have to rev the engine to stop it from stalling.  When I did get home, I let off the gas and it died right away.  Yesterday, I took off the gas cap and started it up and it idled nicely for several minutes.

So ... I freely admit that I don't know that much about bikes.  I did some reading on this and other forums, and it seemed that two possible causes were mentioned.  One was that there might be sludge in the tank, and when you fill it up, it mixes it into the gas, which clogs the carburetor.  A lot of people seemed to mention poor gas tank venting as a cause, so I thought I'd give that a try.  I did have to remove all those venting hoses when I cleaned the carburetor, and I'm not sure that I put them all back correctly (like those two that seem to just run back behind the seat), but when the bike is running well, it's running really well.  I would think that if I'd screwed up those hoses somehow, the bike would run poorly all the time.

Anyway, if anyone has any ideas, I'm all ears.  I'm going to try cleaning the gas cap first.  Based on  Boofer's input, I guess I'm going to just try to break it down as far as I can and spray WD40 on all the pieces (while wearing my safety glasses and steel toe shoes   )

Thanks in advance for your input.