Bowl vent tubes

[Brad]

From the back of the carb, is the bowl vent tube on the right or left side? Thanks Brad.:)

[4with4]

There should be one on each side of the carb.

Ian

[Brad]

Thanks Ian.

[racer7x]

Nice avatar Brad, I have 3 or 4 of those ..

[Brad]

Thanks racer7x Some dealer was handing them out at a swap meet
thats the only one I have left, should of grabbed more!!

[Aless750]

Where is the best place to put them? some guy told me under the bar pad? and is it both tubes on each carb that i have to do that with?

[hontri]

Good article on this in tech section.VENT TUBE ARTICLE (http://www.vmax4.com/tech1.htm)

[Aless750]

Thanks!!! Sometimes i forget to chek in the tech section...

[Brad]

I thought it was only one of the tubes, someone posted there vent tube pics a little while ago i forgot who! And the tubes were vented to the upper part of the air box. Not sure if there were 8 tubes vented or four.

[4with4]

There are 8 tubes off of 4 carbs. You can "T" them together if you wish. They don't really move any amount of air but they do keep the pressure outside and inside the bowls equalized so the jets can siphon off the right amount of fuel compared to how much air volume is passing through the carb. One thing you must be careful of is if you move them from their stock position below the carbs, make sure you don't have a low spot that hangs below the carb while the end of the tube is above the carb. This can create a situation like a plumbimg trap where fuel can sit and affect the balancing of the float bowl to the outside pressure. If you bring your tubes up to the airbox or handle bars, make sure where the tube enters the carb is the lowers point so any fuel that happens to get into the tube from the sled upsetting, gets drained back into the bowl. You can "T" down to 4 or 2 or even 1 tube before you vent to the final destination. When I put the Vari-Flo on mine, I went to 1 tube before I put it in the bars under the pad.

Ian

[Brad]

Thanks for the good tips on the vent tubes:)

[SRV540]

so it really does not make a difference weather, youvent to air box or handlebars....as long as there are no low spots bebore the carb?




There are 8 tubes off of 4 carbs. You can "T" them together if you wish. They don't really move any amount of air but they do keep the pressure outside and inside the bowls equalized so the jets can siphon off the right amount of fuel compared to how much air volume is passing through the carb. One thing you must be careful of is if you move them from their stock position below the carbs, make sure you don't have a low spot that hangs below the carb while the end of the tube is above the carb. This can create a situation like a plumbimg trap where fuel can sit and affect the balancing of the float bowl to the outside pressure. If you bring your tubes up to the airbox or handle bars, make sure where the tube enters the carb is the lowers point so any fuel that happens to get into the tube from the sled upsetting, gets drained back into the bowl. You can "T" down to 4 or 2 or even 1 tube before you vent to the final destination. When I put the Vari-Flo on mine, I went to 1 tube before I put it in the bars under the pad.

Ian

[4with4]

Probably more of a personal preference than anything else. If you go to the airbox, go to the top side (above the shelf) to avoid the carb pulses that exist in the bottom half. And yes, make sure there is no lower spot than the place where they enter the carb.

Ian

[VMAX535]

4with4 are you drilling int the box? or what? Any pics? I am heading into the garage now to pull carbs and do other maintenance and want to route the tubes as well.

/Dan

[4with4]

Mine are up to the bars hooked up with a vari-flo system. I beleive others just drill them into the side of the boxes and use rubber grommets or silicone to hold them in place. They don't have to be airtight.

Ian

[racer7x]

Mine are up to the bars aslo, but hook to the Tempa Flow..

[VMAX535]

Thanks 4with4, What is a vari-flow system.

[4with4]

A vari-flo is a little gizmo designed by Holtzman engineering that lets you lean out your jetting from what you have in your carbs by adjusting a knob.
They work well if you're going up or coming down a mountain and changing a lot of elevation. Thry also work well for temperature changes. I beleive the temp-a-flo is more automatic and I've heard a lot of good thing about them as well.

Ian