Air Filter Cover Holes?

Hi, I just purchased a 87 Venture Royal with 46,000 kms on it. It runs great and it was one of the best purchases I have made. Is there anything that I should be watching for? Also I have heard that some people drill a couple holes in their air filter cover and it increases the mileage, is this true, or is it a bad idea?

Larry Biever

Answer 1:

Scott MacMartin

Hi Larry, I am sure that others have already responded to you on this. I would not recommend putting holes in your air box for three reasons: Air intake drone will increase (this is an annoying low frequency noise that appears with heavy throttle at low rpm). You may lean out your mixture. If a bike was set up very rich (which would require that the owner had already done something incorrect with the carbs), then extra air would increase the mileage. However, I would recommend that if you are getting poor gas mileage to get the carbs set up properly instead.
Gasoline engines in general are VERY inefficient by design. The "throttle" is in fact a device to make the engine suck on a vacuum, which uses a great deal of energy. All auto-cycle engines use throttle to control the horsepower produced. If you want better gas mileage you need to manufacture a bike using diesel engine (which has no throttle losses), or aitkensen cycle (which has lower throttling losses). Well, have fun driving. Enen if we are both forced to drive an auto-cycle engine. ...........

Scott MacMartin Ottawa, Canada

Answer 2:

Dave Leonty First I have heard of it. Allowing more air into the airbox MIGHT increase mileage by allowing the fuel/air mixture to be slightly leaner but this also could increase the operating temps., especially at the exhaust valves. Like I said, first I have heard if it.

Dave Leonty XVZ12 Royale

Answer 3:

Wayne Orpe Larry, some of us up in Calgary have drilled a few small holes in the air box. Some have got a bit better gas mileage and some have not. We also lower our needles in the carbs. With doing this we can get 50 to 65 miles to the gallon. But I think that our carbs are different than yours.

Last update: 11:42 AM Sunday, September 26, 2004

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