Wow Mr. President! Welcome to this humble website. I had no Idea you were fond of old BMX bikes! Or should I just say "Yes you are wrong" 100% wrong in fact. Ok where do I start? The Yamaha Moto-bike was made for three years 1974 to 1976. They were as follows:
1974 was the A model it came with a solo saddle three piece pin style cranks with rubber pedals and the lower body portion of the fork was painted to match the frame. The rear fender and chain guard were made of metal and chrome plated. The handlebars were chrome plated as well.
Then in 1975 came the B model these came with a banana seat and the top shock mounting point on the frame was lengthened to provide an anchor point for the new seat brace. Other than the banana seat and its mounting provisions it was essentially the same as the A model. Except the handle bars and the chain guard were painted flat black instead of being chromed.
And finally in 1976 came the C model. This last model had many more improvements mainly to save weight. The pin style three piece cranks were replaced by one piece cranks with an “American style” bottom bracket and rat trap pedals. The fender and chain guard were made of plastic. The lower body portion of the front forks were now made of aluminum instead of steel and not painted but left bare. The C models were also shod with a true BMX knobby tire instead of the older diamond tread “Tractor grip” tires like the A & B models.
Now as far as your frame is concerned Mr. President though similar to a Yamaha Moto-Bike to the untrained eye, to the trained eye it is as clear as the rapidly graying hair on your nappy head that your bike is not a genuine Yamaha Moto-Bike.
1. The fender hoop at the rear of the frame does not have the very distinctive “kick up” bend like a Moto-Bike All three model years came this way
2. The brace/gusset that incorporates the top rear shock mounts is friggin’ huge and the wrong shape compared to the B & C models that came stock with a banana seat.
3. The tubing size shape and overall configuration of the rear trailing arms construction is all wrong.
4. The front fork is also incorrect as well. I’m willing to bet that if you measure from the center of one fork stanchion to the center of the other fork stanchion it will measure narrower than 5 ½ inches
5. That wide flat brace welded to the front of the seat tube between the two smaller tubes running more or less parallel to the top tube is NOT found on all three model years of the Yamaha Moto-Bike.
6. The serial number (located on the bottom bracket) on all model years of the Yamaha Moto-Bike start with J60 (That's jay six zero.) no matter what! I'm also willing to bet your bike does not.
7. The down tube on your frame is not strait it has a curve to it. do I really need to continue?
If you had your bike and a genuine Moto-Bike sitting side by side Mr. President the difference between the two would be plain to see. As plain as the flat nose on your face!!
By the way Mr. Obama except for the grips and tires the yellow example is all original unrestored and one of the first 1000 ever made.
Also I gave it full over haul befor it up on bay 
