2008 velocity 150cc scooter manuel - 2008 Diamo Velocity 50

you can make your own with gasket paper its not real paper but thats what some company call this. there is a number of thicknesses, or just use some gum exhaust gum take the exhaust off clean the area with wire brush and put back together using the gum run engine for 10 15 min and leave to cool down and its then sealed.

yes I am trying to find a maual

heres a 150cc manual ,, maybe this will help you, I'll keep looking for the exact match http://www.familygokarts.com/manuals/ace/arrow150_engine_service_manual.pdf and heres another http://www.jmstar.com/vendee/UserManuals/JSD125T-12%20and%20JSD150T-19%20-use.pdf its a velocity what ? I think that first one I am sending will do the trick for basic needs

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 !

=)