Dyno Test: Effects of a Dirty Air Filter on Horsepower
How much horsepower are you really putting into the pavement?
Whether you’re working with two wheels or four, if you want to know what you’re really laying down when you hit the throttle, the dyno test is a great way to find out. We used the dyno to find out the horsepower on our 2008 Honda CBR 600RR motorcycle.
However, we threw in a twist: swapping out air filters to see what difference dirty and clean air filters make on horsepower. You probably already know that moving air through the engine efficiently is important, but we wanted to show how much horsepower we’re giving up by not having a clean air filter.
CBR 600RR Dyno Test with a Dirty Air Filter
First, we ran the dyno performance test with a dirty air filter.
Our operating temperature was about 205 degrees, and we ran the dyno on the SAE standard smoothing level 5 for the test. Then, we spun it up and got the Honda CBR into 4th gear.
After four runs, we got results of 99.61 HP, 97.6 HP, and 98.3 HP. We also had an outlier run of about 93. When you average those three good runs together, you end up with an average horsepower of 98.5.
CBR Dyno Test with a Clean Air Filter
After cleaning things up a bit, we installed a new OEM air filter for our 2008 Honda CBR 600, which was the same model filter as the old one.
Watch the video below to see how to change the air filter on a Honda CBR 600.
In the video above, we cleaned and reinstalled a high-flow K&N air filter, but for the purposes of our dyno test we used the same air filter model both clean and dirty to get an apples-to-apples comparison.
Four runs later, we could see the difference. Our runs showed 104 HP, 104.21 HP, 104.26 HP, and 104.47 HP. Those four runs averaged out to 104.23. On a bike that’s a little over 400 pounds, a new clean air filter makes a big difference in performance.
Now that you know a clean air filter improves the horsepower performance of a motorcycle, you should at the very least clean or replace your bike’s air filter every time you change the oil. If you have a dirt bike or ride often on dirty roads, make sure you inspect the air filter more often, and clean or replace it if necessary.