Has anybody ever had a carb "bored and rifled"?

[swampthang]

I seen a 86 R listed for sale that said the carb has been bored and rifled. Has anyone ever had this done to there carb? What kind of advantage or dissadvantage would this give the machine? This is new to me most of the time someone says there carb is bored out they usually just have a larger main jet in it but after searching the web for awhile I have seen pics of some wild rifling on some carbs. I'm guessing it would have something to do with fuel atomization? Kind of like a Tornado you put in your cars intake to spin the air.

[250rAL]

Sounds like snake oil to me. The less turbulance in the intake tract the better.

[Scootertrash]

Sounds like snake oil to me. The less turbulance in the intake tract the better.


Are you talking before the carb or after the carb?

[fabiodriven]

The less turbulance in the intake tract the better.

That's not always true. A certain amount of turbulence is desirable sometimes for atomization. I know this for a fact with car engines, but I'm not positive if it's the same with two strokes.

[El Camexican]

That's not always true. A certain amount of turbulence is desirable sometimes for atomization. I know this for a fact with car engines, but I'm not positive if it's the same with two strokes.

I would think that prior to the reeds you'd want as straight a shot of air as possible. After that I'm guessing the nature of a 2 stroke mixes the fuel and air up pretty good compaired to a naturaly aspirated 4 stroke. Anyway the whole idea sounds kind of silly unless you drive wide open at all times. Got to be better ways to spend cash.

[swampthang]

here's one of the pictures I've came acrossed of a carb thats been "bored and rifled" http://imageshack.us/photo/my-images/149/carb2.jpg/

[just ben]

here's one of the pictures I've came acrossed of a carb thats been "bored and rifled" http://imageshack.us/photo/my-images/149/carb2.jpg/ kind reminds me of the inserts that were sold in the 90's to promote better fuel atomization. I notice that you don't see this product anymore except for the rice burning cars and can only be found on ebay from chinese importers or chinese sellers. I have never tried one but I'm guessing there is a reason the concept never really caught on. I think it's probably like the "banjo minnow" good concept that makes sense but doesnt work

[muthey]

I have a wire mesh insert on my dodge w100 pickup, fitted into the carb gasket and it does make a differences, but that is a four stroke type motor. I don't see any gain by doing that to a two stroke, with the mesh as the oil would tend to get caught on the the mesh, however that is different from what they are doing. I guess the only way to find out what it does is to try one of those carbs out.

[El Camexican]

here's one of the pictures I've came acrossed of a carb thats been "bored and rifled" http://imageshack.us/photo/my-images/149/carb2.jpg/

Glad you posted that, photo I couldn't find one. Looks like someone with too much time on their hands and an obsession with fire arms came up with that idea.

[fabiodriven]

After that I'm guessing the nature of a 2 stroke mixes the fuel and air up pretty good compaired to a naturaly aspirated 4 stroke.

Very good point Camexican. I should have thought of that.

[badass350x]

glad you posted that, photo i couldn't find one. Looks like someone with too much time on their hands and an obsession with fire arms came up with that idea.

lmao!!!!!!!

[beets442]

As far as boring carbs, it can be done, but all your going to get is a mm or two. You can change the slide angles for different applications. IMO, I would just get a bigger carb.
The best thing you can do for the intake is to keep the reeds and carb as close to the cylinder as possible.......Beets

[RubberSalt]

About the only thing that works as far as inserts is the X wing from boyesen, and things like that. They are used to reduce turbulence going to the carb. You want velocity before turbulence. More velocity,=more air and fuel going in, turbulence will slow down the speed of air.

[jmax857]

Carbs are also just a big venturi, which speeds up the air by using the same volume of air, and squeezing it through a smaller orifice, and helping het better fuel atomization.
This was more common back in the day when larger aftermarket carbs wernt so readily available, or reasonable.
The larger bore on the carb would let more air through just like a bigger carb. You could also change the angle of the venturi aswell.

[El Camexican]

As far as boring carbs, it can be done, but all your going to get is a mm or two. You can change the slide angles for different applications. IMO, I would just get a bigger carb.
The best thing you can do for the intake is to keep the reeds and carb as close to the cylinder as possible.......Beets

Yea bigger carbs are cheap compaired to what it takes to mess with boring a small carb. The few guys I know that have done it ended up spending more time trying to get them working afterwards than it was worth in the end. Re your comment: "The best thing you can do for the intake is to keep the reeds and carb as close to the cylinder as possible" I assume you mean for best top end performance, right?