Hello, everyone!  I was recently given an '87 Savage that had been sitting for 4 years in a garage.  The bike's chain tension adjuster had worn out.  I fixed that with a new one and cam chain, had the valves set and carb cleaned.  I also swapped the stock petcock for the raptor.  Everything should be good to go.

When I put the gas tank back on the bike, I installed an in-line fuel filter and connected the fuel line to the carb.  NO FUEL FLOW.  Okay, I took the fuel line off the carb, and gas started flowing.  So, I know there's no blockage in the fuel line.  I reconnected the gas line and loosened the bolt on the carb bowl, and gas started coming through the line.  As soon as I tightened the bolt back, fuel stopped flowing.

The bike sounds like it wants to start, but it's just not getting enough fuel.  The fact that fuel is in the bowl makes me think there's no blockage in the carb, but I don't know what else would keep the fuel from flowing into the carb.

Any advice?

Sounds like your vent tubes are blocked... ...
...(when you open the bowl drain, it's releasing the vacuum and letting the fuel flow into the bowl)...

My first trial would be to remove the fuel filter and replace it with some sort of tubing, or replace the whole fuel line minus the filter. If the bike then starts and runs (your original post said the carburetor was cleaned) you know the filter is the problem. From the experimenting I did with filters, I would try to mount the filter in such a way that fuel enters it from the bottom and the air in it can escape from the top toward the carburetor. Personally, I doubt the air in the filter can "backflow" back toward the tank, and I think it has to go out via the carburetor. Remember this is a gravity flow system, and the pressure is only about half a psi, less if the tank is low.

Okay, so I got the bike started, but it doesn't want to idle without giving it a little throttle.  Fuel doesn't seem to be flowing very well.

I got all the rust out of the tank last week, so there shouldn't be anything big clogging up the raptor petcock screen.  And the fuel filter looks clean.  I had to completely block off the carburetor vents to get it started.

Any ideas?

It isn't a matter of the fuel filter being clean. The filter is full of air, which is blocking the fuel flow. As I said before, remove the filter and try it. If it runs, you will have to do something else with the filter.

In my earlier experimenting I used a small fuel tank (from a Toro SnoPup, if you care) with a few inches of clear fuel line and a filter. The line and filter hung straight down from the tank, with the outlet of the filter dumping into a catch funnel and gas can. I blocked the outlet of the filter with my finger, poured the tank full of gas, unblocked the filter outlet, and NO FUEL FLOWED. When I bent the fuel line so the filter pointed up, fuel flowed into the bottom and displaced the air, and then fuel flowed as it should.

You may take the results of the experiment for what they are worth. I point out that the reason for the experiment in the first place involved an attempt to install a fuel filter in a Honda Elite 80 scooter. It ran until its fuel tank was half empty, then quit. Filling the tank made it run again. Removing the filter solved the problem.

You have a filter on the raptor.

My savage started for the first time in 4 years today!  That's awesome!

What's not awesome- it will only start if the carburetor vents are plugged.  I have swapped fuel lines (one w/ a filter and one w/o a filter) and that didn't change anything.  Even with the vents plugged, the bike would not run if I wasn't giving it some throttle.

Like I said, this bike has been torn apart and sitting for the last 4 years.  I just de-rusted the fuel tank, put a raptor on it and installed a new cam chain and adjuster.  

Do you think the carb just needs adjusting?  I had it looked at about 4 weeks ago.  It came back clean, so I don't think it's a clogged carb issue, but I could be wrong.

There is definitely something wrong. I'll try to post some pics when I get home from work. When the bike was running, I had to keep giving it throttle or it would immediately die. I'll grab some tubing for the vent lines today, too.