Honda Spree and Elite 50 Forums

Is a boost bottle worth it on a 50cc would u see any low end performance gains from this cheap mod if the bottle volume was correct

Depends on what kind of riding you will be doing.it won't do anything for wot riding. Its more for on/off/on throttle response traffic riding or circuit racing style riding on a canyon style road or mountain road.

It will b on the spree motor fitted 2 a go kart for my kids to thrash in the fields so lots of on off throttle and not a lot of wot runs .also these 44 bbks wat size in ccs does this make the spree does it add tourqe 2 push the kart with me in it its a tad gutless with me in it

Comes out to about 63cc. If its for than then don't waste your money on the boost bottle. Play with the sproket size.you could be stressing the trans and motor with to small of a rear sprocket and burning up the clutch.

Greetings;

I calculated 57ccs from the 44 working through the 37.4mm stock stroke.

Its geared good for the kids it tops out at about 20mph which is fast enough for them now was just wondering about the kit as its a pretty tired motor ive done the intake mod new k-n filter in a adjustable air box and made a new exhaust actuall a made 5 to get 1 that worked its only a little more for the bbk than buying a stock kit when i get something i intend on opening up the intake ports and wideing the exhaust port should help the tourqe i hope does this sound right

Yeah the kit should help in adding torque. Don't port it. Porting the exhaust looses the torque if you don't have to right pipe and transfer timing to match. Use that kit with a stock exhaust to get the lowend grunt your looking for. Just make sure the head is cut to the diameter of the bore and the squish band is cut to the correct degree angle.

I was going 2 widen the port not raise it and match it 2 the exhaust the exhaust ive build works for low end not high rev. Iv read that the 48 bbk is hard 2 tune why is this is the carb 2 small for it as it hav a range of carbs that i could use.is there a big jump in ponies when going 2 the 48

honestly dont know about these bbk's but a properly running/built non restricted single cylinder 2 stroke should have at least 9hp per 50cc up till about 250cc then the physics change and the increase starts dropping example 70cc should equal about 12hp(+) while 250cc be about 45hp(+), but a 500cc is only about 65hp(+), hope this helps the carb and pipe you decide to use will have a big effect on output but expect to double your power

Wat gas do u all run these on all my dirt bikes run on race fuel so thats wat the spree motor is runing on seems 2 like it (for now)

that guy wrote:Wat gas do u all run these on all my dirt bikes run on race fuel so thats wat the spree motor is runing on seems 2 like it (for now)

You are wasting your money and race gas. The Spree has a 7.2 to 1 compression will never need more than regular pump gas. Until you get to something like 9.5 to 1 you do not even need premium pump gas. You need at least 12 to 1 for the minimum octane race gas.

Ive got a 80L container of the stuff we use in the dirt bikes and drift car so not bothered bout the cost i get a deal on it

What would the advantages of running this on a dio motor with a 28mm carb and malossi cast iron? I've never heard of a boost bottle

i believe the theory behind it is that there is a sealed bottle/cavity exactly equal to your engines displacement that is connected to your intake manifold just like the petcock, and on your first initial intake stroke the air is sucked out of the bottle, then after the initial stroke there is negative pressure that sucks in an air/fuel mixture and physics over compensates and the mixture is actually under pressure for a second so on the next intake stroke there is an already mixed charge of fuel and air that is being pushed rather than sucked into the engine, this should be more of a throttle response thing and would only add power at lower rpm, you should look up a helmholtz exhaust resonator same concept but in reverse and i actually have one on my dirt bike look up fmf power bomb also

So i made a boost bottle 4 the nq powered go kart and the kids reakon its better my boy says he can do figure 8s now alot easier i had a go didnt really notice much difference a little like everyone said it only when punching the accelerator on and of it picks up the revs a bit faster