Bogging on takeoff  By  lain (Read 6,837 times)

Alley has a very good tutorial on how to tune your carb. What you describe is a classic tuning symptom, so before you pull a new carb apart I'd suggest you get your idle mixture set properly and your main jet sized properly.

And --- CONGRATS ON YOUR NEW BBK BEAST!

Here is the Step by Step tutorial on how to tune your carb that RCQ92130 is talking about. Even Shop owners have copied it to be used in their shop when working on scoots.
Alleyoop
itistheride.boards.net/thread/12/4ts-carb-tuning

Have to disagree with your simplified tuning. It is a step by step and what the results should be and if not what to do to correct the situation. You should read it and take some pointers your never to old to learn you know.

Like I said , mine is for tuning , yours covers more in depth if someone needs to learn the ins and outs , and problems that you may have. U can use mine if you have a carb that is 100% sound no problems such as leaks etc. Since I'm 100% carb inclined I have no need for to take a class on carb tunning. Thanks anyway

You ought to give it a rest bud, your jealously is really showing.
Alleyoop

I am really a very street smart guy been around the block more than I care to think about. So I will tell you this and chew on it ok, "I may have been born late but not yesterday". Your not as clever as you think you are..LOL
But do me a favor before I do you a favor:

I have a bunch of jets, but found the # to be best for me so far, but I will be experimenting after the blizzard. 

I've done a lot with my scoot, but even before I installed the BBK I had a higher top speed and pickup than most 50cc stock scoots. The top speed is even higher with the BBK, by I think 30%. 

Before I installed the BBK I had already installed a performance variator with slider weights which helped a lot with reaching top power faster. I then installed 1.5K RPM clutch pad and torque springs which really helped me with taking off faster and climbing hills.

I had also installed a Kevlar drive belt, a decision I made after trying to figure out why I was going through belts at the time I had a delivery job on the scoot and was going through belts each month. After installing the kevlar belts hills gave me a lot less resistance if I had some speed already, though starting from a stop going uphill was always horrible on 50cc. There are many very steep hills in Boston so this was a big plus for me. I stopped breaking belts even when I found my bendix at the time was rubbing the belt as it was running, but those belts are bullet proof! lol

I then installed the cone type air filter, you know the ones that look sort of like coffee filters? It didn't really make much of a difference in performance on 50cc, but changed the sound of the scoot. I am guessing it is good with the BBK, but I haven't used my air box in forever.

I messed around with slightly lighter and slightly heavier weights, giving me different results being faster pickup or higher top end speeds.

Ultimately I moved onto the BBK to get the higher torque to be able to quickly speed up to avoid crazy Boston drivers, and so I could coast at 30-40 instead of redlining to ride there constantly. I get top speed of around 60, and can get to about 30 in 1 second if I really need to from a stop.

This is the kit I got: www.ebay.com/itm/100cc-Big-Bore-Performance-Kit-GY6-50cc-139QMB-Chinese-Scooter-Parts-50mm-Bore-/161018154007?pt=Other_Vehicle_Parts&hash=item257d6e0c17&vxp=mtr

I used everything from it except the oil pump and gear for it. Mine works, why replace it? lol

The only different KEY COMPONENT I used as in this kit it came with thin metal head gaskets, I ended up ordering a thick head gasket because starting up the BBK was really hard with super high compression. the thicker gasket lowers the compression a little bit to allow easier starts. Might also have something to do with my different performance? But we also have different scooters we started with, even though the engine may be the same there may be small seemingly irrelevant differences that may change things so very slightly but in a tiny engine like this even a very slight difference can mean the world.

That ebay seller starrider02 is a very good seller. They have great customer service, if you need help they have good advice too. A couple times when I messed up they sent me small replacement parts like piston rings and gaskets for free! The parts they have are good quality too as far as I've seen. I have bought a great starter motor that has little issues pushing the 100cc kit over from them, the BBK kit, twice but only because I messed up the first time, a great KeiHin carburetor, fuel filters, main jet packs, speedo drive gear, fuel pump, intake manifold, stator, stator removal tool, and some other stuff and everything I have bought from them has had no issues except for my own ignorance when I first installed the first BBK the first time a few months ago.