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A ramjet? get real. a ramjet needs fuel for be ignited to the incoming air which increases the temperature between the inlet and outlet. and since PV=mRT if temperature goes up so must pressure if all other variables are the same. this pressure increase is our the back which produces thrust.
Without the gas being ignited it is simply a nozzle

Mass flow rate is density x velocity x area which gives you an amount in mass/time unit. usually lbm/s or kg/s. Assuming that the density and velocity aren't changingby any huge amount and the area is shrinking the mass flow rate must go down as well.

The only part that is throwing off my calculation is the "ram air" that the scoop provides. It is actually catching air at roughly the velocity the scooter it travelling. However at a stand still it is hindering the fans ability to suck in air from all angles.

The ram air might help if you had air holes drilled around the fan so the excess air can be blown around the fan. The fan is already blowing as much air as it can when operating at the engines rpm. Blowing ~45mph air into a scoop and around the bend will not provide enough force to increase the fan's rpms.

The scoop is a good idea, but i think it should be directing air into a stagnant spot though. Maybe direct the air onto the bottom where the oil drain plug is, but that would require a lot of modification to the scoop.

Yeah thats what i figured I would do. I am at college right now so i'm kind of limited on my tools right now.

I have done the variator thing before too. I found that I was about a quarter inch away from the edge of the variator when I was using the stock belt. I did some calculations and calculated that in order to get to the edge I would need to go from a 906 belt to something ~20mm longer if I remember correctly. I found a 918mm belt online somewhere and I installed it hoping it would still get to the bottom of the clutch and the edge of the variator. I again marked the variator and it is maybe a little bit closer to the edge but I figured out that the belt was not getting all the way to the shaft on the clutch. I had to go back to the 906 belt.

This motor uses something like an extra long case motor since 250s usually use 906 or 918mm belt so it's all sorts of goofy.

I also have a stock 123mm variator with a large belt. I think it's 906 mm. I will have to double check. The engine number is XY157QMJ-3 which has little to no info that I can find. I have talked to scrappy about BBKs before and he has had hardly any experience with this type of an engine...

Ok I tried a couple different "velocity stacks" and brought my needle up about one notch. Since my needle on this scooter isn't adjustable i just used some really really small washers haha. I used 2 to raise it...

First one I tried was a radiatior hose and it had a bend in it. It was a little more naroow than i would have liked. Got it all rigged up and sounded good on the center stand and when I thought it was in the ballbark of a/f mixtuer I went to ride it and you could tell the main jet was a bit too rich. It would bog after about 20MPH, but ran great up till then. I would let off the gas and it would stay around 20 MPH and not surge ahead, telling me rich. I fiddled around and finally said screw it i'll try the other pipe.

Pipe two was a rubber necking or whatever you call it. I think it's mean to connect two pvc pipes or something. I tested it's heat capacity by holding a lighter to it to see how easily it would melt, it didn't hardly give so i think it will work fine. The pipe is kind of an adapter going from about 2" to 1.5". The 1.5" matched up perfectly over the carb and made a really good seal and the 2" side went over the air filter and it was a tight squeeze. Since the adapter went over the air filter, I took the ring, used to tight the air filter usually, off and tightened the adapter to the filter. Once tightened I check inside to make sure there were no kinks or anything. I left the needle the same setting and adjust the a/f mixture till i thought it was good. My speed is back up to 62 indicated which is a touch more than I had before.

I took it on about a 10 mile run and have been checking the plug and it looks a lot better now. I took some picture but can't figure out how to post them haha. Before when it was hooked up right to the carb, the base of the plug where the threads start was kind of black now it is a more brownish color. Overall it is running pretty smooth throughout all throttle positions. I will try to post these picture on a photo bucket or something...

Thanks JR, so far so good. I think i'll leave good enough alone until this longer belt gets in

I'll run to the hardware store tomorrow and grab som radiator hosing that will fit and see if we can get more speed...