SPEEDOMETER FOGING

[07bigdog]

The temperatures here in Canada are getting down to below 40 degrees. After riding for a while the speedometer starts to fog up around the tripmeter button. As soon as i stop riding the speedometer face clears itself. Is this normal, or is it a warranty issue? No problem in warm weather.

 

[KnotSo]

This is an on going issue.

I solve this problem by rarely looking at the speedometer.

 

[Mad Dog]

I think everyone has issues with speedo fogging. I'm with KnotSo. Listen to the wind and go like hell!:up:

 

[BigDogBro1]

These gauges are not air-tight sealed so any moisture in the gauge will condensate inside the unit when the temperature gets low. Mine did it on the last cold ride as well.

I work for a company that manufactures weapons sights. We purge (using a vacuum) any air from inside our sights. We cycle purge and fill several times with dry nitrogen then seal the unit with an o-ring screw. It's the only way to make sure no moisture will be inside to cause fogging.

As for our Bigdog gauges the best thing to do is not spray wash directly into the trip meter button area. As for rain - put a shower cap over it?

I was thinking on trying to place a 1/32" thick o-ring around and under the trip meter button bottom lip rubber and the gauge glass to better seal that area. Cost just pennys to try it! O-ring diamter size - maybe 5/16" to 3/8". My black reset button is loose in the glass.

There is a service bulletin for this problem, I think.

 

[RRRUFF]

Hey guys I thing Gasman had thread on this complete pictures.

 

[ROCKETDOG]

There is a plug in the back of the speedo. You can unplg it and let the speedo 'dry out' - worth a shot.

 

[RRRUFF]

Yea I think that's what Gasman did and he put a self-adhesive felt pad over the hole to allow it breath and keep the dirt out.

 

[Gas Man]

Yep its in the how to section linked in my sig.

It helps but is not the 100% fix. The speedo may fog up slightly but will clear fast after

 

[TSDAWG]

SPEEDO! Your Speedo fogs when cold? I bet it shrinks too! OH...I'm funny!

Yes. That fogging is part of the "uniqueness" of the Big Dog! You paid good money for that customizing. I do agree with Knotso, but it's also a great excuse for why you were doing 100 in a 45!

 

[Ratman]

Plug removal/felt did not work for me..and Chris was great trying to help me as always. I also put a mesh screen over the speedo plug hole-and it got worse. Last attempt, I removed the plug, and then taped 2 silica gel packs over the hole. Then I used a sheet of styrofoam around the outer part of the speedo (where the wires are on the inside) to try to keep air from flowing into the speedo head. Then used landscape fabric and by trial and error, made the biggest silica gel pack I could fit in the pod and tied off with zip ties. Lastly, I pushed as much foam as I could up through the bottom of the speedo where the wires go through thinking it would 1) stop air flow into the pod and 2) the more I could fill the pod there would be less air to change temps. I have rode 10-12 times since all of this over the last six weeks or so-and for the first time my speedo has not fogged once. HOWEVER-it has turned cooler and less humid here in NC and I don't know if all this fixed the problem-or if it is the humidity/temp change. BD should truely be ashamed of putting a piece of junk speedo like these that fog on a 30K bike.

 

[Gas Man]

Rat... you are simply a man of many talents... and with a solution like that... I'm betting a field engineer... :lol:

 

[RRRUFF]

Yea I like that too Rat! The more air you can keep out the less moisture present to condense on the glass. Love the ingenuity of the group here on this forum.

 

[Ratman]

Thanks guys. Not saying it is THE solution...but it has worked so far and I probably will not know for sure until higher temps/humidity comes around again. I am very appreciative of Gas for trying to help me with his method but unfortunately we have so much humidity here in NC his method would not work for me. Until then...working on a better way to mount playing cards against my spokes than using clothespins. (Sorry-had a 50 year flashback!)