Question about boost bottle

[300EXer777]

Hey I have a question and i was wondering if you could answer it for me. I like to look through a lot of fourwheeling magazines and I always see something called a boost bottle. Could you explain to me what exactly it does.

[skemp]

It is supposed to equalize the pressure in the reed cages on twin cylinder two strokes. There usually isn't much of a problem with reed pressure to begin with though. I haven't ever seen a boost bottle make a noticeable difference on a sled, but some guys claim they get better gas mileage.

[Glow Plug]

a question for spemk if its sopst to work with a twin engine then why do the make em for a blaster?



but anyways for what I have heard/ read the don't really work

[nacs400ex]

I always thought a boost bottle held the fuel and air mixture, so that when the throttle is hammered it will react quick due to the extra mixture. I cant really explain it though. Oh well I dont have a need for one.

[D11NR]

They make for a good pen and pencil holder:blah:

[wilkin250r]

Here's how I understand it.

Air is rushing through the carb, reeds, and into the crankcase. Suddenly, the reeds snap shut. The air coming through the carb still has inertia, so it compresses a little against the reeds, and then decompresses BACK through the carb, causing a double-rich mixture for that small amount of air.

The boost bottle sits between the carb and the reeds. Instead of air compressing against the reeds, it goes through the bottle. This eliminates the "double rich" mixture. However, now your bottle is slightly pressurized. The other end of the bottle is connected to the other intake, which is just opening up, so the pressure goes there instead of going back through the carb.

So, by eliminating those small pockets of double-rich fuel/air mixture, you improve throttle response.

At high rpms, the reeds are opening and closing so fast, the air doesn't have time to compress against the reeds, so a boost bottle isn't needed.

So, that's the basic theory. How much does it actually help? I don't know, I've never tried one, but the general concensus seems to be that they are a waste of money. Who cares about low-end response on a banshee anyways? If you're not WOT, then why are you riding a banshee?

[Toadz400]

Originally posted by wilkin250r
Who cares about low-end response on a banshee anyways? If you're not WOT, then why are you riding a banshee?

lol...true

i need more low end on my banshee because of the trails i like to ride on, but other than when i'm on the little amount of trails...i'm all WOT:cool:

i have tried out a boost bottle, and it seemed like it didn't have as much hesitation on low end when putzing around, but the guy who rebuilt my banshee took it off when he rejetted it because he said it was causing problems?:confused:

[300exOH]

A friend of mine has a Shee that is set up for low end power for trails and when he tried the boost bottle he got a major low end hesitation. Not sure if he tried to rejet or not though. He said it was a waste of money and got rid of it. It seems like a gimmick item to me.:blah: