hissing gas cap

[jeff]

theres a noise comeing from my gas cap...when i stop i here it...after i open the cap it draws a lot of air..and the noise is gone......i havent had the bike long.....is this normal..its a high pitched sound...l

[skimo]

Yes, but here away to fix it.

http://www.gadgetjq.com/whistle_stop.htm

[Yellow Jacket]

Hi Jeff and welcome.

This noise is normal. Some bikes do it more than others. If it annoys you it can be fixed.

Check out Gadgets fixit site at:http://www.gadgetjq.com/gadgetsfixitpage.htm

The specific page that addresses this issue is at: http://www.gadgetjq.com/whistle_stop.htm

Cheers, Bob

[unwind2]

My does - esp if it is warm out. It doesn't bother me I just tell myself it's the bike talking to me. ;)

[ruruson1]

Mine does it, it normal and only in hot weather.

[nighthawk700]

On the Concours list we would refer to that as the bike singing to us after enjoying a good ride.

[Cajunrider]

Mine does it after a ride in the heat. It annoys my wife but my high freq hearing is so bad I can barely hear it. Welcome aboard.

[racinchef]

I've got a 2000 carburetted and it does it. I always thought it was just my bike sucking it up after hauling my fat ass all over creation.

[jeff]

thanks for everyones help......that took a worry out of my life....thanks again.............jeff

[beezer]

I cut a loop off the spring in the cap and it doesn't do it anymore.

[dui546]

Older Yamaha 650 Specials had a similar problem with tank venting due to the design of the gas tank cap. AND, if the vent got plugged with dirt or debris it would cause a vacuum in the tank which would lead to the engine carburetors being starved for fuel. The problem would be experienced during long rides and/or long acceleration. In the most extreme case, the engine would ultimately stall. The quick fix was to open the gas cap, start her up, and ride on. However, the best fix for the Yamaha problem was using a drill bit by hand to slightly enlarge the holes in the cap's orifice plates.

I also noticed this with my Nomad and my concern is that a similar or related problem to tank vacuum or pressure could occur during long rides. I appreciate the information for correcting the problem and I will be completing the fix.

[unwind2]

Originally Posted by dui546

Older Yamaha 650 Specials had a similar problem with tank venting due to the design of the gas tank cap. AND, if the vent got plugged with dirt or debris it would cause a vacuum in the tank which would lead to the engine carburetors being starved for fuel. The problem would be experienced during long rides and/or long acceleration. In the most extreme case, the engine would ultimately stall. The quick fix was to open the gas cap, start her up, and ride on. However, the best fix for the Yamaha problem was using a drill bit by hand to slightly enlarge the holes in the cap's orifice plates.

I also noticed this with my Nomad and my concern is that a similar or related problem to tank vacuum or pressure could occur during long rides. I appreciate the information for correcting the problem and I will be completing the fix.

Oh man! You mean I should get rid of my hissing cap?

[dui546]

Unwind, I believe that is an excellent question for Blown Dodge.

I never read of any fuel problems on the Nomad that could be linked to the gas cap besides the hissing. I haven't had my Nomad long enough to know it as well as my antique Yamaha and I pay attention to what the guys say who have.

However, I can attest that the gas cap on the Yamaha Specials impacted power and gas mileage on long distance rides. I personally think that air having problems getting out could be easily aquainted to air having problems getting in during the fuel drain through long term or high power engine operation. I clipped 1/2 a round of spring off of mine today. I will see if that makes any difference.

Does anyone have any thoughts on the subject?

[bobzinger]

I just did the Gadget mod and at most it took 10 minutes.