It seems that there is a little debate over the reliability of the pumpless mod. Here is what I do with at least 5 pumpless bikes under my belt without issue...

Purchase Grizzly Needle Valve and replace the stock one with it

Remove the carb inlet filter

Set float level to 2004 and up specs

Either trim the "on" tube from the petcock, keep the petcock on reserve, or buy a Pingel High Flow valve. If keeping the stock valve make sure it flows well. Remove it, whether you are modifying it or not, and check the screen/filter to make sure it is clean and clear. It's a good time to pick up a rebuild kit and replace the gaskets and o-ring.

Run 5/16" fuel line from the petcock to the carb going over the top of the intake. An inline filter is optional and if you choose to use one make sure it is a high flow (I have had good luck with Russel brand filters - plus they are serviceable). If there is doubt about the filter just don't use one. Make sure the fuel line doesn't have a lot of slack in it - you want the straightest line to the carb as possible.

Vent the gas cap AND make sure the vent line going to the tank is clear (both going into the tank and the rubber line that goes to the roll over valve). I blow compressed air in both directions just to be certain.

Make sure the roll over valve is functioning properly or just get rid of it - Personally I just remove it.

IMO - most people get into trouble with the tank not venting properly so the last 2 steps are just as important as the rest of them.

Please treat each step as important as the next. All too many times when people have issues they, for some reason, have skipped a step somewhere.

Thanks for that. A larger number of people around here lately are complaining of problems with it, and when you get down to it, they are not following the tried and true formula to get it done right. Half or 2/3 of a mod seldom works well.

Is this something to do because it's better or something you do after your pump fails?

Stevie wrote:
Is this something to do because it's better or something you do after your pump fails?

A lot of us do it because it cleans up the looks of the bike, and allows more airflow around the jugs. It works very well, for stopping carb puke. Some have had the pump fail at a bad time, and decided just to leave the pump off. Some do it because it's just extra stuff,

My only question's in doing this is running the fuel line over the intake vs. under it??? Its a little cleaner install over the top, however I found it to be really tight when trying to get the fuel line onto the inlet of the carb and was concerned about pinching the line, also with the heat in AZ in the summer, was concerned about vapor lock with the line on top of the intake.

I never cut the main tube on the petcock either, but with a non working fuel gauge it really doesnt bother me when I switch to reserve, I know how far I can go before I run out of reserve

Is there another reason for cutting it down???

Rod

HotRodRStar wrote:
My only question's in doing this is running the fuel line over the intake vs. under it??? Its a little cleaner install over the top, however I found it to be really tight when trying to get the fuel line onto the inlet of the carb and was concerned about pinching the line, also with the heat in AZ in the summer, was concerned about vapor lock with the line on top of the intake.

I never cut the main tube on the petcock either, but with a non working fuel gauge it really doesnt bother me when I switch to reserve, I know how far I can go before I run out of reserve Is there another reason for cutting it down???

Rod

I'm in the under the manifold camp, also. It does look a lot cleaner, with it run over the manifold, but all the heat is at the top where the heads are. Under seemed to me, to be the better choice.

I run over the manifold, for the even cleaner look, but by cutting down the main feed tube of the petcock, and now, I always run on the reserve setting of the petcock... I'm tickled with the look and performance. No issues ever! (and nothing else done either)

that makes sense.. Quest.. Weve got a gas gauge anyway...

HotRodRStar wrote:
My only question's in doing this is running the fuel line over the intake vs. under it??? Its a little cleaner install over the top, however I found it to be really tight when trying to get the fuel line onto the inlet of the carb and was concerned about pinching the line, also with the heat in AZ in the summer, was concerned about vapor lock with the line on top of the intake.

I never cut the main tube on the petcock either, but with a non working fuel gauge it really doesnt bother me when I switch to reserve, I know how far I can go before I run out of reserve

Is there another reason for cutting it down???

Rod

Trim your "On" tube and you will still have reserve. It won't be as much of a reserve, but there will still be some miles left to get you to the station (hopefully). I guess for me the gauge is just a bonus since many of my bikes required the "open the cap and shake the bike method" = no gauge. On long trips I tend to go by mileage anyway. If you use a good fuel line (I use the line intended for higher pressure fuel injection) it won't pinch. It is available at any auto parts store. Honestly I think the fuel line over or under the manifold is the least important step, since the gas tank is higher it should work either way especially if your running no filter. Fiter's can get a little finicky if their angle is off by getting a bubble in them. I always hook the line up to the petcock and leave the carb end disconnected and put it over a drain pan and let gas run through it for a couple seconds to get the bubbles out. This is also a good test for flow. It should come out as good as if you were draining right from the petcock.

Mr_Shamrock wrote:
HotRodRStar wrote:
My only question's in doing this is running the fuel line over the intake vs. under it??? Its a little cleaner install over the top, however I found it to be really tight when trying to get the fuel line onto the inlet of the carb and was concerned about pinching the line, also with the heat in AZ in the summer, was concerned about vapor lock with the line on top of the intake.

I never cut the main tube on the petcock either, but with a non working fuel gauge it really doesnt bother me when I switch to reserve, I know how far I can go before I run out of reserve

Is there another reason for cutting it down???

Rod

Trim your "On" tube and you will still have reserve. It won't be as much of a reserve, but there will still be some miles left to get you to the station (hopefully). I guess for me the gauge is just a bonus since many of my bikes required the "open the cap and shake the bike method" = no gauge. On long trips I tend to go by mileage anyway. If you use a good fuel line (I use the line intended for higher pressure fuel injection) it won't pinch. It is available at any auto parts store. Honestly I think the fuel line over or under the manifold is the least important step, since the gas tank is higher it should work either way especially if your running no filter. Fiter's can get a little finicky if their angle is off by getting a bubble in them. I always hook the line up to the petcock and leave the carb end disconnected and put it over a drain pan and let gas run through it for a couple seconds to get the bubbles out. This is also a good test for flow. It should come out as good as if you were draining right from the petcock.

...and also a good way to flush any boogers out of the new set up, that may get snagged by the needle and seat.