can you explain this? boost bottle truths

im just trying to keep the performance improvements as low budget as possible. . . for myself, thats the fun in it

Amen! good for you!

Huffydavidson said:

Manic 57 is right they got me to back in the beginning.
It does so little to improve performance its not worth the money.
For the same amount of money you can have a nice RT carb
and you'll have noticeable increase performance.

Click to expand...

I agree, the RT carb makes a nice low end increase and very nice throttle response, I still get more top speed with the little NT carb, but low end power and response is really improved with the RT.

The boost bottle gives a higher manifold capacity of atomized fuel readily available for the motor and makes perfect sense in its claims to smooth idle and increase some low end slightly, of course on such a small engine the margin is small but it works... I suspect why they don't use boost on 2stroke motorcycles at this point is current engine designs and reed valves being introduced.

several very knowledgable engine builders on here say there is NO benefit to using a "Boost Bottle" on these little engines, they idle just fine without any contraption like that on them and since the little 2 strokes are very low on torque to begin with and the normal range of use is in the mid to upper RPM range I see very little if any benefit to using them in hopes of getting any noticeable torque increase.

A well tuned carb, and low restrictive exhaust, the right gearing for the riding condition and weight of rider and the engine will do all it can do which is a pretty good job, my bike will scoot me down the road plenty fast for me, two of them top my 215+lbs out at 43-46 MPH and pull me to speed at a good pace, look at all the racers bikes at the motorized bike races running these engines and you wont see one of the fastest and hardest pulling bikes running a "Boost Bottle"... reason being they add no performance, if they did they would all be using them.

It's a neat novelty but on these china girl engines that is all it is in mine and many others opinion, but I say if a person like it and thinks it helps something by all means run one, I know the people selling them will appreciate it.

Map

Ya you don't see them on race bikes anymore due to the aforementioned in my earlier post,,that's true, Yamaha did boost bottles for years. It can however help to some small degree if setup correctly to help improve on drivability on the street with the extra atomized fuel readily available with the manifold volume being increased with the bottle, it can help with engine/throttle response and so on, not in the mid and upper range like a race bike. Though like I mentioned the motors are small and so with that the percentage is small and obviously may help with some setups more so than others.. Race bikes have other mods designed for different conditions/applications than someone trying to make there low powered bike smoother and more responsive..it is not designed to miraculously boost power, but can help a relatively stock bike take off response wise, Of course with engine mods your overcoming that initial response hopefully and your probably not in need of this devise.

the theroy makes since .. catching the reversion of the fuel mix as it blast back before reaching the carb and refeedingvit properly.

however on a 66cc low tech motor like this would it make a differance .... no lol on a high comp yamaha blaster with the right carb and volume intake .... **** yes !

like map bike said it all depends on the motor in question . but if u think its gonna make your china girl fasteer its all in your head lol

i would like to see a china girl dynoed with and without one then we can talk .

Initial Throttle Response and making engine run smoother are the possible benefits, engine is too small to significantly do anything else dyno wise and will not make the bike faster, I actually mentioned different motors in question. Of course there are variables especially size of motor. For example a Bone stock Banshee it makes them more throttle responsive, so coming out of a turn and jumping on it can help but that's a different animal altogether. Like I mentioned it is not to make bike run faster but in some applications can make the bike run better...drivability wise..which in turn can be a faster transition on and off the throttle..

I had a yamaha blaster with a big bire kit fully ported for high rpms and wow an stainles steel boost bottle custom made from high preasure pipe fittings and hard colaps re$istant braided hose made a HUGE DIFFERANCE during initial take off and coming back on the tjrotle after a high rpm run and a quick drop off ... But on a china girl .... Dont make me laugh ... You get the best results useing a long intake or a powerplenum itake like freds design.

Then you know where I'm coming from Roger, and of course there are some alternatives for achieving similar responses....go ahead and let it out bro...you laugh if you want to.....

What's next, N.O.S. ?

Greg58 said:

What's next, N.O.S. ?

Click to expand...

Maybe a mini blower to go on it..?

What if we put NOS and a mini blower on it...

Davezilla said:

What if we put NOS and a mini blower on it...

Click to expand...

Oh My.............!

Think pf a boost botte like this ... A real well designed and tunned one can add throttle responce and hp to the bottem end and help out when comeing back on the throttle after being on it for a wile hard and xomeing of then back,on .... That is where it shines...

But then that is where it shimes on a 50hp high epm yamaha blaster thats 196 to 250cc

It can addd 10% hp to the low end rpm range and take off and 10% of 50hp is like an extra 2.5hp more at the crack of the wrist on a performamce atv it can be felt and the gain is measurable and noticable

But a china girl is only like 2hp to begn with .... Lol so what do u think you wil gain ? even if it could add 10% to the bottom end .... We dont use that rpm,range and even if we did it would only add about .2 hp tp it lol do you think you are going to notice a .3hp increse ? Noooo...
That is why we laigh and say it a waste of money for this type of mptor

If you were running an 80cc piston port demo saw capable of spinning 15,000 rpm i would say yeh go for it on a high rpm demo saw thats 80cc and tunned perfectly you will notice a small gain in throttle reaponce and off the lone torque.

Honestly though you will get better results by running a 16mm ID bore intake thats 6_7in long or running a shorty intake with a plenum port that has the same volume as a 16mm id 6in long intake

All joking aside, if anyone is getting better performance with a boost bottle good for them. Sometimes you get things just right, by luck or by using what you have on hand and it works great.

Personally I'd never recommend a boost bottle on a China girl but if someone already has one I won't tell them to take it off... most everyone I know that ran one didn't really notice a difference other than smoothing out the low range...

Extending the intake and port matching everything from the carb to the cylinder will net much better gains before any money is even spent... and adding a pipe with an expansion chamber will totally change the way it accelerates and sounds... best bang for the buck, even those banana pipes will do a considerably better gain for the same money than a boost bottle.