F6B's for sale

[JackB]

It could have been a bad tank of fuel, but the bike had pinged several times earlier, just not as badly as that one time. I rode it for over 40,000 miles and it definitely required higher octane fuel than my 2016, which has never once exhibited a hint of detonation. Maybe it's those louder pipes on the 2016 covering it up!

I've seen this before. I have a '98 Valkyrie Tourer I bought new that runs fine on the 85 octane fuel they call 'regular' here at high altitudes. But I have a '99 Valkyrie Interstate that knocks badly on anything but premium when the weather is very hot. The Interstates had an ICM with a faster advance curve to compensate for the extra weight, so that could be a factor. Since I bought it used it's possible the P.O. installed a trigger wheel. Interestingly, the Interstate also gets considerably better fuel mileage than the lighter Tourer. But there's definitely a distinct difference between the two bikes, even though they use virtually the same engine.

My Interstate also got about 5 MPG better than my Tourer. If you do have a trigger wheel than you need to run premium fuel

[F6Dave]

My Interstate also got about 5 MPG better than my Tourer. If you do have a trigger wheel than you need to run premium fuel

That's about the same mileage difference I see. It's surprising what a gas hog that Tourer is. One time with strong headwinds in Kansas I got 17 MPG!

I need to change out the timing belts on the Interstate so I'll see if the previous owner installed a trigger wheel.