Im gettinga knocking noise from the engine when the bikes hot. Going out of first gear and really in any gear if i really punch it, just the first few seconds. And like i said only when the bike gets really hot, after sitting in traffic in 70 plus weather. After its hot though forget about it, the engine will knock and the only way to stop it is to let it fully cool off. What causes this? i run the highest octane gas i can get. i hve a 2001 1200 with 11,000 miles, i dont know the maintenance history, doesnt seem to be good.

 

I dunno...........but i had the same symtoms when I used 92 octane...... Now I just use regular 89 octane and never have the problem. You could also look at the possibility of it being a carb issue as well, and make sure you have proper main jetting. There's a bunch of other things that can also lead to knocking like symptoms. Also when you said it happens when you gun the throttle, are you paying attention to your rpm's......just to eliminate that it's not the rev limiter kicking in. Or is it happening due to high load acceleration.

 

I've had the same thing happen while sitting in traffic, too; I get a metallic knocking noise. It also happens under high load acceleration. The only thing that I've done, and this helps to prevent it, is to ensure that the engine isn't overloaded. When I'm going from a stop, I'll feather the clutch more to ease the engine into gear.