Motorized Bike Boost Bottle vs Fred Head 

The "idle screw" is a glorified mix screw

+ThunderHead289 ah, no its not.

thank you make it fit. there is only one mix adjustment on a NT carb. the needle inside the slide. there is NO OTHER MIX CONTROL except jet size,... but that's not an adjustable "control" accessible from outside the carb.

+DANIEL Q thats more of a low speed mix screw and should be used as such to set your carb up for best low end and top end performance

If my bike stalls on idle I then turn clockwise will open up the carb. If bike has high idle turn counterclockwise.

turning couterclockwise opens up the screw and richens it. while turning it in leans the carb down, resulting in a higher idle speed. same concept on a holley carburetor, where the mixture screws are adjusted for the highest idle speed then turned 1/4 turns richer. - but the curb idle screw is the actual idle adjustment, just like the slide adjustment on these carbs. some time i will put a vacuum gauge on my bike and demonstrate this.

+ThunderHead289 the idle screw has nothing to do with rich or lean. if you want to lean or richen the the engine, look inside the carburetor inside the sliding barrel there is a 1 1\2 brass needle that contains a c clip with a few notches. u move the clip up or down and that will give rich or lean

that is still not your mix. yes im aware, i run mine one notch richer to protect my engines. again, its not quite how you may perceive it to be. its just like a motorcycle carburetor.

Kurt Smolik definitly should not be. that is the idle air/fuel mix screw. not idle speed screw. experience - i drive a carbed car every day and i make many of the holley carb adjustment videos.

That is the idle screw. It controls how far the slide opens and closes. You adjusting the cable is doing the same exact thing. Turn the screw in and it raises the slide. Tighten cable also raises the slide and vise verse. Its not the same as your Holley or most other carbs. This carb only has 1 jet. A main jet. No pilot jet that most other carbs have thus having no af screw. The needle clip controlls your fuel mixture from idle to half throttle. The cable adjustment on top of the carb should only be used to take the slack out of the cable. Not to make carb adjustments.

hey, fair enough. good work. i just looked at mine and there is a good chance that i am in error.

i do believe this is a mixture screw of some sort after disassembling my spare carb.

I've been trying to decide on an expansion chamber for awhile now. Need one designed for max low en torque. I don't go over 25 though I can do 38 currently

Yeah, it’s because they all have reed valves - not an open intake port. On an open intake the boost bottle functions as an economizer to dissipated the reversion style intake pulses associated with an open intake port to the crankcase. Thunderhead289 - engineer

+nvrqit nope, sure wasnt outside of the air cleaner

oh really - go have yourself a look at the slide and turn the screw. tell me what you see.

+chfar072281 throttle cable adjustment is % throttle used. adjust it down, your using less of your throttle to idle and thus, less fuel. carb screw is more of a mix screw. as you lean the carb, the idle will rise, as you richen it, the idle will fall. strong misconception here it seems.

If your throttle cable is tightened to the 0 position of your carb slide, does adjusting your carb needle accomplish the same thing?

it still doesnt, your really adjusting a very primitive slow speed mix circuit. if thats how yours is set up, you have one of two things going on. you have an adjustment up by your throttle that does the same thing. but also you may have a vacuum leak that is sucking in air and you are having to compensate with the throttle opening being very low.

Should I loosen my throttle cable all the way, then adjust my carb, when I reach operating temp, then re-tighten my throttle cable?

im trying to remember how this all goes together ha, this vid was the last time i rode by bike. adjust your throttle cable so there is no play in your throttle itself, but dont keep tightening after the play is out. do all your actual adjustments at the carb. i personally always had a vacuum leak issues on my stock carb till i sealed if off by having one round of electrical tape around my intake. does that make sense? i show it in my main carb adjustment video.

hemi stands for HEMISPHERICAL COMBUSTION CHAMBER. so yes,.... these are in fact hemi's. LOL wait till I tell my buddies I got a hemi on my bike!

***** im sure it would, it would probably be even worse where the boost bottle might even work better. obviously a set of reeds would work best. but when you can make your own boost bottle for under 5, why not. i bought mine, but i wanted a reference.

Sparky Parkinson i have never tried, they run quite a bit of back pressure as is, but if you wanted, you could weld up holes in the exhaust baffling and drilll them out smaller. i dont recommend this.

I have my bike running finally and tbh it is quieter than I had expected. The two stroke 49cc stock exhaust does its job superbly.

nvrqit what's the name of the online store where I can buy this Fred head

nvrqit its an ebay engine..reguardless whos the vendor its all the same only diffrences maybe intergraded cdi and external..and maybe diffrence style carb and filther..

i believe so, they are all the same

@@heathgraham4911 thanks buddy

all good mate

What were your issues? I have run them on 3 different bikes and they have worked awesome

It just acted funny. It acted almost like it had an air leak with it on there. At idle when I'd rev it up, it would take way to long to come back down. I constantly had to adjust the idle back and forth even after running a while. When I took it off, my throttle response came back and it idled fine. One thing about running it that I noticed even with the boost bottle off is that when i get up to a certain higher rpm the engine kinda bogs for about 2 seconds then kicks back in and runs fine getting up there around top speed. I'm not sure whats up and I've tried everything I can think of. For some reason though in my case it just runs better with the bottle off but it's still not perfect. Is there anything you can think of that might be the problem? Right now I am not using the bottle and have the HP carb installed. With this carb the throttle response is awesome and it idles fine but still has some running issues. By the way. Do you know the torque setting for the head bolts? I have them at 12lbs right now.

I'm willing to bet money that somewhere along the boost bottle line you had an air leak. somewhere. that is THE classic air leak issue--slow idle return. a pinhole anywhere along the line will be enough to cause your problem,.... brotato chip.

Rimshot Recluse sounds like a dirty spark plug or clean connection from magneto to crank case. Seeing there's oil behind magneto. Clean oil off and sand paper any paint inside magneto compartment

+RundeKatze im assuming the vehicle has something like reed valves inside of it, so it is far better than anything a boost bottle could ever do! but do some research and see. whats your top speed btw!?

100kph (at full throttle around 110-115)

nice, so about 60-70mph.

Yes. I don't want a boost bottle for "boost" i just want to reduce the bumpy running of the engine when I am at around 1/8 or 1/4 throttle. And I want a better fuel economy. At the moment I am at around 6l per 100 Kilometers on the freeway. But in the rushour traffic you're at 10l per 100Kilometers. And maybe a boostbottle can help to make the engine running more smooth.

again, do some research on your engine to see if it has any sort of reed valve or anything. if there is nothing, then the boost bottle will work well for what you want it to do. boost bottle is a terrible name, it should be called an economizer bottle. as to the size you need for your engine, you will have to look up the math on that because to be honest, i just dont know. i know these are for the bikes, so i wasnt worried about the math. id imagine yours would be moreso the size of a peanut butter jar.

Boost bottle if your cruising under 25 like I usually do.

ThunderHead289 ] ur videos are great] thank you]

Dan smith Most likely he is running the stock 70 jet

+Noel Santos i never said they had anything to do with each other. both are just performance options. and honestly, they both compliment each other very nice in the low rpm range.

you run Reed valve? how good is this?

I'm pondering that. Thing rips pretty good the way it is. Carbs are my specialty.

+ThunderHead289 go to thatsdax.com and buy his 15 dollar clone

when this summer comes around and if i get back into it, i will give it a shot. a well tuned stock carb rips pretty good from my experience thus far. especially on the bottom end

a dialed in stock NT carb is the best option ive seen. the other carbs out there are one headache after another until you smash it against a wall,...... and put your stock NT back on. the dellorto,..however,..is superior. but these bikes are cheapo chinko. why put a expensive work of art on the wall of a wooden shithouse?

I'll have to look that up. Obviously I have the boost bottle. If it's a nitrous kit then don't use it. It's a fuel oxygenator and you have no way to inject fuel so you'll have an extremely lean condition. That equals a blown engine

Dean Klass he said it was a knock off Mr dumass