I am using projectors for shadows...When I use particles for bike speed up i.e., nitro speed the particles get cutout by those shadows....

Here is screenshot of it,

Here is my shader code of projectors ,

Shader "Projector/Projector Multiply Black"
{
    Properties
    {
        _ShadowTex("Cookie", 2D) = "gray" { TexGen ObjectLinear }
    _ShadowStrength("Strength",float) = 1
    }

        Subshader
    {
        Tags{ "RenderType" = "Transparent"  "Queue" = "Transparent+100" }
        Pass
    {
        ZWrite Off

        //Fog { Mode Off }

        Blend DstColor Zero

        CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#pragma fragmentoption ARB_fog_exp2
#pragma fragmentoption ARB_precision_hint_fastest
#include "UnityCG.cginc"


        struct v2f
    {
        float4 pos : SV_POSITION;
        float2 uv_Main     : TEXCOORD0;
    };

    sampler2D _ShadowTex;
    float4x4 unity_Projector;
    float _ShadowStrength;

    v2f vert(appdata_tan v)
    {
        v2f o;


        o.pos = mul(UNITY_MATRIX_MVP, v.vertex);

        o.uv_Main = mul(unity_Projector, v.vertex).xy;


        return o;
    }

    half4 frag(v2f i) : COLOR
    {
        half4 tex = tex2D(_ShadowTex, i.uv_Main);
        half strength = (1 - tex.a*_ShadowStrength);
        tex = (strength,strength,strength,strength);
        return tex;
    }
        ENDCG

    }
    }
}

Here is my particle code,

// Simple additive particle shader.

Shader "Custom/Particle additive"
{
Properties
{
    _MainTexture ("Particle Texture (Alpha8)", 2D) = "white" {}
}

Category
{
    Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" }
    Blend SrcAlpha One
    Cull Off Lighting Off ZWrite Off Fog {Color (0,0,0,0)}

    BindChannels
    {
        Bind "Color", color
        Bind "Vertex", vertex
        Bind "TexCoord", texcoord
    }

    SubShader
    {
        Pass
        {
            SetTexture [_MainTexture]
            {
                combine primary, texture * primary
            }
        }
    }
}
}