is there any way to stop the relays from burning out on the series 2. can you fit the relays from a series 1

 

They operate differently so are not interchangeable plus the S1 relay has the rev limiter in it. The S1 relay fails due to a dry soldered joint where as the S2 relay burns tracks out.

I can repair the S2 relays depending on the damage. Have you kept any of the old ones?