light pinging

I have a 117 with 10:8 compression. What could be causes of light pinging and tingling noises when rolling along at 75 mph in 6th gear and slowly roll the throttle and the noises are present only between 78 to 86 mph. No noises above 86 or below 78 mph. I stopped and added some gumout octane booster to the 91 octane gas but the exact noises continued to occure at the exact same speeds.,,, Any thoughts?

Believe it or not I had the same noise at about 65=75. Turned out to be a loose heat shield.

will double check heat sheilds since they were removed recently, but noise seemed more topside internal.

As mentioned, check all of the simple things first. After you do that and don't find anything loose, then start looking at engine issues. I am assuming that your 10.8:1 compression is static and not your corrected compression? Correct?

how long have you had the motor in the bike and or is it something from the start or a new development? carb or fi?

just had the cases bored for 117 kit just got the motor together. have the tts master tuner Had it dyno tuned at 500 miles. have roughly 1100 miles on motor.The temp was high 90's on a 500 mile trip.

Bike ran and runs good. was curious about the noise sounding like ( low octane gas at acceleration) but at the speeds between 78 & 86 mph only. Noise was low key

noise only appears at acceleration between those speeds whether slow roll of the throttle or a good twist. More pronounced with a quick twist. Could it be trying to somewhat lope while crusing at 75 mph in 6th gear with that big bore engine

have not traveled any hills. I am wanting to think it may be the gas. If it was running a bit lean wouldn't it occur at speeds other then between the speeds of 78 and 85 only? It only happens when the speed has leveled out while running along at 75 mph in 6th gear and slightly or good twisting of the throttle to pass or simply accelerate a bit. My main concern is does it sound like a ensuing problem. Have heard suggestions to not even run in 6th gear under 70-75 mph with the big bore engine ? I am new with engines other then stock.

If try gasoline without 10% ethanol first (if you have it in your area ).
www.pure-gas.org.
You should find listings in your state where it's available.

May have found cause for light ticking type noise while accelarating from cruising in 6th gear from approx 78 thru 86 mph. Have a slight leaking header exhaust leak at rear cylinder that may be causing change with lean problems.

yup, that would do it

Replaced header gasket. Problem seems to be solved. The problem made bike run a bit more hot also. All appears ok now