Foggy tach and speedo glass

[Breezerider]

My tach and speedo tend to fog up a few minutes after starting a ride.  I'm in a humid cold climate and I think the instrument light is vaporizing moisture where it is condensing on the instrument glass.  I"m tempted to drill (carefully) some vent holes in the instrument cases, but I don't want to make them vulnerable to dust contamination.  Anyone have a better fix?

[larstorders]

Me too.  
I'm in England and my R65 clocks are the mistiest of all 4 BMs I've had. Never got round to finding a cure. Hoping someone will share the secret. Hoping there is a secret  :-/

[aussie]

Had the same problem - but drilled a VERY small hole in the 'glass' face and presto - no more of an issue  

Cheers

[larstorders]

Won't the rain water get in? Ooops forgot. You're in Oz.

[aussie]

Won't the rain water get in? Ooops forgot. You're in Oz.

Yes - it has been just a tad dry here of late, but I did it back in 2000 just after I got the bike.

I spoke with a BMW mechanic and he said it was a fairly common occurrance and it was he that suggested it - he said that he had been doing it for years. Apparently the issue stems from teh fact that the workings of both instruments makes it hotter than the surrounding air at times - consequently the fogging. The idea is that you try and even some of the temp. It was done at the very top of the face and the bike has been out in some fairly heavy (torrential) rainfall - much like a fine summers day in the UK -and there have not been any issues. Now when I say a very small hole I mean just that - the finest bit you can find.

However - like you I did have reservations at the time - but seeing that I couldn't actually read either instrument I figured I didn't have a lot to lose - but I also carried some blue tack to 'plug it up' just in case. It hasn't leaked but maybe you need to have a chat to your local mechanic to see what the feeling is over there...

Cheers

[larstorders]

Thanks Aussie. So that's what's going on.  I'd never have figured it out. The clocks generate just enough heat to cause condensation, only BMW could achieve this   . Smallest drill bits will be out tomorrow. I'll be tempted to drill through the side of the metal case up near the instrument face so the hole will be shrouded from the rain but still vented. Luckily I have a scrap tachometer I can practice on.

[montmil]

Had the same problem - but drilled a VERY small hole in the 'glass' face and presto - no more of an issue   Cheers

We are talking about a plastic dial "glass" aren't we? A tiny, tiny hole is all you would need... smaller than 1/16". Like a numbered bit from a well-stocked hardware store.

Monte

[aussie]

Had the same problem - but drilled a VERY small hole in the 'glass' face and presto - no more of an issue   Cheers

We are talking about a plastic dial "glass" aren't we? A tiny, tiny hole is all you would need... smaller than 1/16". Like a numbered bit from a well-stocked hardware store.

Monte

Yes it is plastic - I was going to type perspex (?) - but then I chickened out as I didn't know how to spell it...   And yes, the absolutely smallest bit you can find - think I stressed that (at least I hope I did).

[nhmaf]

I've always been timid of drilling the plastic lens to deal with this - on cool evenings up here in new hampshire I definitely get the fogging occurring - usually all around the edges where the numbers are !    I've thought of drilling carefully instead into the top of the metal case which would also be covered by the plastic cowling on my LS, just in case of torrential rains, etc.    If one of you guys can post a picture of your "instrumental surgery" and let us know how well it worked, I'd be much obliged !

[Bill Conquest]

I've got the same problem with my r65 but only in the tach. Here in Hawaii it rains alot so i'm a little worried about water getting into it...  looking forward to learning from this!
Bill