I just bought a 06 ZX6 with Akrapovic slip on muffler about 3 days now. Every morning I let it warm up for about one minute and when I took off the next block when I was changing gears it stall out and restart ok, it only happens once in the morning. After restart and riding is ok. Is this normal for ZX6s? should I let it warm up a little longer? I got a 07 CBR before and I doesn't warm up before I go and it doesn't stall when the engine is cold.