time delayed relay for spec application

I have a old motorcycle that has customized back brake and turn signals. All of the bulbs are double filamented w/ one filament used for running lights. Right now the turn signals use the brighter filament for the turns and the brakes use the filament for the brake. However, I would like to wire the bike so all three function as brake lights and the turn signals still function as turn signals. I have a diagram drawn up and I bought two 5 pin relays. The idea is that the default (non-energized) circuit would be the brake wire and when I hit the turn signal the turn signal wire would fire up the electromagnet and switch the circuit to the turn signal. The problem I ran into is that the way my bike was designed there are no wires designated to the left and right side respectively that have a constant flow of power running through them. So when I energize the electromagent with the pulsating wire it keeps switch between the brake and turn signal circuits which causes the bulb to light up with the brake circuit and brighten slightly when is switches to the turn signal. Sorry if I didnt explain that clearly. Hopefully you get the gist.

So basically I need a 5-pin timer delay relay so that when I turn on the turn signal the circuit switches over to the turn signal and holds for a couple of seconds so that the next pulse catches it and continues to hold it in the turn signal circuit position. I do not however need a delay on the brake circuit.

Is this possible? What relay do I need?

https://www.the12volt.com/installbay/forum_posts.asp~TID~114615~KW~brake+blinker+~PN~0~TPN~1#555268

The letter A on the center relay connects to terminal 87 of the left relay.