Boost Bottles

[2strokd]

What do you think about a boost bottle on a 70cc mild motor? They are so easy to make i just gotta give it a try. I made this one out of a protein shot container, it is 2.6 fluid oz you can pick them up at wal mart I use another one for extra pre-mix oil in case i need to fill up while out and about.
I used to put these on quads and the would help the midrange, and keep em in the power when in and out of corners, and shifting. Im not sure if they will help much on a scoot, but for free its worth a shot .

[90GTVert]

Can't hurt to try it. I thought of trying one myself, just never did it. I believe that you are supposed to match the volume of the boost bottle and plumbing to the volume of your cylinder. A 2.6oz bottle and tubing would put you around 80cc or just shy. The bottle itself should be 76.89cc. If it works and you decide you wanna play with different sizes, you can make your own custom sized boost bottle using PVC materials. Just use a section of pipe and glue on end caps then tap it for a fitting. Keep us posted.

[2strokd]

I put one together and installed it, i went ahead and ported my intake a little more while i had it off. Heres a pic of it on my scooter

I couldnt do any testing yet, when i opened my garage door it was of course raining . My scoot doesnt hook up very well at all on wet roads, plus open air filters dont like water so guess the glue has more time to dry

[Rebel]

hey, sit back have a cool drink and enjoy the smell of the rain. The sun will shine another day and riding in the rain is not smart in my opinion.

[2strokd]

I agree Rebel, riding in the wet can be fun sometimes but im not going to be testing for power in the rain thats for sure. Nope, im chilln and a cold drink sounds pretty good.

[felliott]

Food for thought, When Yamaha motorcross bikes came out with them years ago, The hose coming out of the boost bottle was much bigger hose to the intake. We were also told by the factory to keep the boost hose short as possible.

[2strokd]

Thanks for the info felliott, i am going to play around with hose sizes, lengths etc. The way it sits i am on the edge. I might need to fill some of the bottle, its a little to big. Im not going to change anything yet though, i havent even got to try it yet.

[2strokd]

Well this is what i ended up with yesterday, and let me tell ya they work.

I ended up matching the bottle and plumbing volume with the size of my motor, 70cc,s. I used model clay to fill my bottle to spec. I used water to make sure it was accurate. The first one pictured made a slight difference, but the theory stands correct that if you match you bottle plumbing and all to the motor size you will see great improvement in throttle response and acceleration, i also got allot better idle out of mine. I didnt see any improvement on top end but i wasnt expecting any. I would recommend a boost bottle to anyone with a two cycle. Heck im building one for my weed whacker right now! j/k, its a thought though. Here is about the perfect size bottle for a 50cc, little big but not much. 2fl. oz

[2strokd]

redhandmoto brought up a good point, heres a link to help better understand the theory of a boost bottle wikiscootia.wikidot.com/boost-bottle

[90GTVert]

Glad to hear it worked out for you. Thanks for giving me something else to work on! I wish I still had the old 49cc boost bottles I built a few year ago, coulda just hooked 'em both up.

[2strokd]

Oh well, now ya got sumthin else to fab

[90GTVert]

The good news is that I have 2 free ports on my Polini intake. The bad news is that a 99cc boost bottle will be hard to hide on a bare frame scooter. My coil sits where your bottle is mounted. The other free space in hidden locations is taken up by relocated electronics. Hmmm. I could try to make it look like a fire extinguisher and mount it to my frame brace lol... or a nitrous bottle. I'll prob be lazy and it will look like PVC.

[2strokd]

Just go shopping, there has got to be a 3+oz container of ?something you can use. You need about 3.8oz right? You could make it look interesting on your frame brace, it would make people wonder what the heck it is.

[90GTVert]

99cc would be roughly 3.35oz. I'll be using PVC for mine. Pretty sure it's gonna look just like a PVC boost bottle. Here's one of them I made for a 49cc cateye midbike. It will prob look like that but bigger... and possibly less beat up lol.

[2strokd]

I made this one for my uncles Cobra, turned out well. On this one i used a bottle with the material a flexible as possible and a flexible bigger hose to see if that helped. Im not sure if it did but the boost bottle does work . Here are some pics.

This is one of the inlet port

And here is one of the inside of the intake, i had to trim about 1/4inch off of the fitting so it wouldnt cause any eddies