Today I'm a very happy boy (53) thanks to alleyoop and new2scootn. I have a 2013 MC_D150TKB. I say 2013 because the build date is Dec. 2012, which answers the question as to if they are making them any more, and if you look at it as cars are manufactured, it's a 2013. But who cares.
I Had the wobbles at 45 to 50 MPH. I read this board for two weeks and this is how i cured my problem
1- i put 5 Oz's of Ride On in each of the front tires.
2- i filled both tires with air exactly to 80% of the max pressure, cold
3- i put 6 Oz's of Ride On in the rear tire, as per Ride On tire size tables
4- filled the rear tire with air as above
5- i squared the wheels and bike up very, very similar to the drawing that alleyoop has posted many many times on the two forums.
6- i checked all the measurements i could to determine weather the front wheels were toed in, toed out, sideways, you get it. I had determined when my bike came assembled and the PDI was done by Scooter Depot, and then did my own PDI, that my wheels were toed in 1/4". By using the drawings alleyoop posted this was definitely confirmed. The trick is to determine which front tire is out of alignment, BECAUSE as new2scootin said the tires need to be parallel, and just as important, parallel with the rear wheel, So you use alleyoops drawings to determine which wheel is parallel with the REAR wheel, and then adjust the other.
7- once you determine which wheel needs adjustment, turn the adjustment arm to remove, or increase, half of the distance that the wheels are not parallel. For me i needed to make that bar 1/8" shorter, which is 4 turns of a flat side. Now my right wheel was 1/4" out. I loosened the nuts and from behind the bike i made 4 flat side turns DOWN, shortening the rod 1/8". I'm being specific because weather it's your right wheel or left wheel or toed in or toed out, it's probably different. Also it depends if your working from the front or back of the bike.
8- Because of this forum and the good people on it, I NAILED IT, (yes like i said I'm a happy boy) the first time.
So for me that is how you get the wobble out of a 150TKB. Make the front wheels Parallel to the rear wheel and your golden.