Xt660R 2004 Co- stock?
 

Hello frends!
I have on me 2004 yamaha c1=47. Im not the first owner and not sure this number is from the factory. As i know from this forum normal C1 for the 2004-2006 year is 5-15 for xtx. Is this number same for xtx and xtr?
ps my bike is full stock.
Now i tune c1 to 15 and hardly see any difference.
What would be the optimal c1 for my engine?