What happens if you run 87 octane in a YFZ?

[RNL]

Like the title says, any ill effects or thingsthat would go wrong?

[XCRacer236]

No. If you get your gas from a station with 1 nozzle, you're getting mostly 87 anyway. Slight decrease in horsepower but probably not enough to notice a difference.

[94racing]

depending on youre setup you might get detonation. ive got mine jetted and hmf exhaust and if it dont run 93/110 i get detonation.

[RNL]

Alright let me ask this. Would old gas cuase the spark plug to be black and sooty? It's not wet, like you would think it's running rich. But I pulled the plug and its black and sooty. Could this be caused by old gas?

[94racing]

Whens that last time you changed the sparkplug out?
Could be old gas i guess

[Rohr397]

The compression ratio of the Yfz450's engine is meant for the higher octane gas. It's really hard to explain but while you might not notice much of a performance problem, you're destroying your motor. Additionally that would most likely explain the carbon on your plug. Stock jetting is set up for the higher octane gas, so there's a good chance you're not running quite right there either.

I know a lot of people who would disagree but it caused problems for my 450, including overheating and the obvious problems related to improper jetting.

[exracer416]

if the picture loads, this is the result of 87 in a 12:1 motor, i bought the quad like this.