Eliminar valores(option) iguales entre combobox

[walterdevel]

Te paso a ver si te sirve:

Código HTML:

<select name="combo1" id="combo1" onchange="borrarOptions(this.value)">
    <option value="a" selected class="select">1</option>
    <option value="b" selected class="select">2</option>
    <option value="c" selected class="select">3</option>
    <option value="d" selected class="select">4</option>
    <option value="e" selected class="select">5</option>
    </select>
<select name="combo2" id="combo2">
    <option value="a" selected class="select">1</option>
    <option value="b" selected class="select">2</option>
    <option value="c" selected class="select">3</option>
    <option value="d" selected class="select">4</option>
    <option value="e" selected class="select">5</option>
    </select>
 

Código Javascript:

<script>
function borrarOptions(valor) {
 
    var i=0;
    var opciones = document.getElementById('combo2').options;
    for(i=0;i<opciones.length;i++){
        if(opciones[i].value == valor){
            document.getElementById('combo2').remove(i);  
        }
    }        
}
</script>