Using Timer 1 to trigger a regular interrupt that executes an I2C command

Hi,

I'd like to attach a timer interrupt to trigger an I2C command 10000 times a second. I'm using a STP16CP05 LED driver and would like it to cycle as fast as possible.

I'm already using timer 1 code below to trigger a clock signal at 4Mhz for another device but would like to know how or if it's possible to use ISR(TIMER1_OVF_vect), triggered 10000 times a second without affecting the 4Mhz D9 pin frequency?

  // Set Flip Flop Clock - Outputs to D9
  TCCR1A = bit (COM1A0);               // toggle OC1A on Compare Match
  TCCR1B = bit (WGM12) | bit (CS10);   // CTC, no prescaling
  OCR1A =  1;

Is there a reason blink-without-delay is not an option?