How do I fix keeway matrix/150 when throttle is given it bogs down and won't allow me to accelerate up to speed

The carburetor needs to be removed and cleaned, water must be in it or some rust from the old can must have got into some of the injectors.

CHECK VOLTAGE WITH VOLT METER AND GAS/OIL MIX COULD BE RUNNING ROUGH

All you have to do is spray some starting fluid in the opening of the air box then try and crack it with the throttle wide open

Here is most of the specifications on your Moped ! You could go through them all, and find out what's relevant !
http://www.scooterpartsplace.com/keeway-matrix-150-gas-scooter-moped.aspx
Links are provide for you to find the :

Specifications

Manufacturers Info

Accessories

Warranty Info

Setup Information

Hope that answers your querry !

=)

Hanyes Chinese tyinese scooter moped repare manual is a good one

buy 2 fuel filters. buy can of SEAFOAM at parts store. use 1 f filter to replace old one(you'll probably see old looking gas, with an odor).Pour SEAFOAM into tank. fill up with PREMIUM gas. after about 100 miles change out fuel filter 1 last time..add SEAFOAM every 3-5000 miles and you should be fine. the ethanol in the gas turns to goop and adds water to your fuel, and puts carbon on your valves and through out your emission and fuel system. The ethanol will be alright as long as you follow these instructions. and the SEAFOAM will keep you from having line freeze up in the cold months ahead, and will give you better gas mileage. good luck.

I found that if I run 87 octane gasoline the engine accelerates up to full speed without the skipping and bogging down at any point it is running. It is worth trying. also try putting some "Sta-bil" fuel stabilizer in the gasoline - it has the ability to keep the carbureator cleaner. Not just during the time you are storing it, but rather all the time.