[Kreation]

#include < amxmodx >
#include < hamsandwich >
#include < fakemeta >

const Float:g_fSpeed = 999.0;

new Ham:Ham_Player_ResetMaxSpeed = Ham_Item_PreFrame;

public plugin_init( )
{
    register_plugin( "Set Speed", "0.0.1", "kreationn" );
    RegisterHam( Ham_Player_ResetMaxSpeed, "player", "FwdPlayerResetMaxSpeed_Post", 1 );
}

public FwdPlayerResetMaxSpeed_Post( id )
{
    if( is_user_alive( id ) && pev( id, pev_maxspeed ) != 1.0 )
    {
        set_pev( id, pev_maxspeed, g_fSpeed );
    }
}

You need to compile it for it to work..