Instrument Cluster Condensation Drama

Matias wrote:

Hi Moto,

I must say I was impressed with the sofistication of the solution you came up with...
You must be the Guru on the subject, so maybe you can give me your opinion on this theory...I believe a saw this idea in some thread....it doesn't sound bad:
- Consider you are not exposed to a big amplitude of atmospheric pressures
- Would it work to seal the cluster completely, having just an elastic membrane (not permeable to water molecules, if that is possible...), or a small tube with a piston inside, that would move inwards or outwards to compensate for those small atmospheric pressure variations...
Could this work or would the water molecules still find their way in through the plastic material structures?

Thanks,
Matias

Hi Matias,

Well, since you asked.

For a long time I had thought about using a flexible membrane just the way you described, but finally realized it would be permeable to water vapor if it were made of any material I could think of or find. The piston is good idea. It would have to have an excellent, long-lasting seal around it.

I went far enough down that path to consider the air pressure difference between sea level and, I think, 10,000 feet. A piston could work, if sealed. But the seal would also have to have negligible stiction so that its resistance to movement would not mask actual elevation changes.

When I researched the matter I lost hope that any plastic material would resist infiltration of water vapor for long. (I think I posted a link in the original thread to an engineering table that showed the amount of transmission over time for set areas of plastic and other material barriers. Interestingly, it is only the exposed area, not the thickness, that counts in the long run, as I recall.)

I now think I may have let the "perfect be the enemy of the good" in abandoning all hope of effective barriers. There has been a change in the venting of the GRiSO dash over time, where the two, original small baffled breathing ports have been replaced by a single, larger port that has a membrane stretched across it. The engineers at Digitek were evidently aware of the moisture problem and made the change for that reason. Though that barrier cannot, as I understand it, block gaseous water (i.e., water vapor) for long, it can go a good job on mists. This change may have helped to the degree that mist ingestion is an important part of the problem. I seem not to see so many postings any more about failed dashes.

Moto

Thanks for the reply Moto.

Unfortunately I can confirm the second version of the dash with the membrane didn't solved the problem.
My first dash was of the first version with the 2 small baffled vents. It was replaced during warrantly by the second version with the membrane. It seemed to work in the beginning. It took a while for the moisture to get, but it did...and it seems it is more complicate to get out...
An alternative to the piston:
- What if you would connect to the vent a tube with a "U" shape, to work as a siphon, with some water-repelent oil inside?

Matias wrote:

Thanks for the reply Moto.

Unfortunately I can confirm the second version of the dash with the membrane didn't solved the problem.
My first dash was of the first version with the 2 small baffled vents. It was replaced during warrantly by the second version with the membrane. It seemed to work in the beginning. It took a while for the moisture to get, but it did...and it seems it is more complicate to get out...
An alternative to the piston:
- What if you would connect to the vent a tube with a "U" shape, to work as a siphon, with some water-repelent oil inside?

Hi Matias,

I had not seen a previous report of moisture ingress with the new design. But I am not too surprised. I guess your new dash has not failed yet?

The U-shaped tube with oil inside is also good. The water-repellant nature of an oil might depend on surface-tension properties of water droplets. (I am just speculating.) If so, gaseous water, which of course has no surface tension as separated molecules, might penetrate the oil surface just as it penetrates plastics. Scientists may have investigated this.

I would also be concerned about the effects of the motorcycle's vibrations and dynamic loads on the oil. Will it aerate? If so, can the water vapor portion of the air escape more easily then? I don't know.

Here's another idea I vaguely remember considering. Since, as I mentioned, the rate of passage through a vapor barrier is a function only of the material's surface area, a thin foil or membrane of a metal could be quite effective as a containment, the permeability coefficients for metals being extremely low. (These coefficients have some other name than "permeability," I think.) Maybe a pleated piece of metal foil in the form of a bellows could do the job, assuming its edges could all be sealed well, including over any folds. (NASA would use gold foil, of course, which is not too expensive and might be easier to solder.)

After a while I grew impatient with mechanical contraptions that I knew would be hard for me to perfect. I decided to create an external desiccator using the tubing guides I found below the dash, and only later realized a conformal coating might be even better.  

Moto

I'll add another point after having re-read the impressive exchange of ideas on the first page.

The problem for the dash does not occur while the water is condensed on the inside of the clear cover. Instead, it is a "rust never sleeps" situation, where the water works its damage while it is not visible, but is sitting condensed on the printed circuit board. This is a pretty obvious point, but it also means that anything you can do to reduce humidity while the bike is in the garage (or stored over the winter) will be much more important that what happens while you are riding around, simply because of the relative amounts of time involved. So this argues strongly for solutions involving bags of desiccants enclosing parked GRiSO dashes, I think.

Moto

Climate controlled garage, with a dehumidifier. Helps with many other issues also.

Mine (1200 Sport) used to but suddenly stopped one day. It might have been a 40+ degree day where the bike was parked in the full sun. It took the dash about 1/2 hour to cool down enough for me to see the details. Since then, no issues.

However, I then got ants in the dash, multiple times, very annoying - they died under the clear Perspex and not behind the workings, as they should have. Now I have desiccated ant carcases in my dash - choice!

I couldn't be arsed pulling it all apart - besides my ability to see really small shit is diminishing, as is my dexterity. Fuck getting old sucks.

sideshowbob wrote:

Climate controlled garage, with a dehumidifier. Helps with many other issues also.

Right. I wonder if anyone with a climate controlled garage and a dehumidifier has ever experienced a failure. Anyone?

Hi,
Thanks Moto. Thanks to all.
To reply to your question Moto, no, my new dash as not failed yet. It would be great if the manufacturer would have decided to coat the circuit board like you did, but I doubt it...Anyway, even with the circuits protected, that fog over the instruments is anoying enough...
Once those humid days come I will report how did it go with the sílica bags

Oz1200Guzzi wrote:

Mine (1200 Sport) used to but suddenly stopped one day. It might have been a 40+ degree day where the bike was parked in the full sun. It took the dash about 1/2 hour to cool down enough for me to see the details. Since then, no issues.

However, I then got ants in the dash, multiple times, very annoying - they died under the clear Perspex and not behind the workings, as they should have. Now I have desiccated ant carcases in my dash - choice!

I couldn't be arsed pulling it all apart - besides my ability to see really small shit is diminishing, as is my dexterity. Fuck getting old sucks.

Hi Oz,
Lets hope your ants get thirsty and drink all that condensated water ...

Desiccated == dead and dried out. So no, I don't think that will happen, Matias

Maybe the desiccated ant corpses absorb the moisture within the air inside the dash! This could be the ultimate solution to our problem!

moto wrote:

sideshowbob wrote:

Climate controlled garage, with a dehumidifier. Helps with many other issues also.

Right. I wonder if anyone with a climate controlled garage and a dehumidifier has ever experienced a failure. Anyone?

I have not.

I'm from Florida, hot and humid. Just got back from a mountain trip to North Carolina, 20 degrees cooler and no where near the humidity.
I always have a small amount of condensation on the lower right corner whenever its cool out.

But this trip as soon as I fired up the bike it fogged up instantly and took a couple hours to clear.

The idea I had was that it doesn't need more vent holes.... it needs a vacuum to draw the moisture out. But how to accomplish this on a bike?

Then it hit me. Use a line coming from one of the intake vacuum ports! That and a small valve petcock valve. In theory it can suck the air (and moisture with it) out. Hopefully it would only need to be run a few minutes. The valve would be to keep gas vapor from flowing up into the speedo when bike is off.

Haven't done it yet... just an idea bouncing round in my head.

That would work! Provided the air being drawn in is low in humidity, say < 40% RH, which is quite dry, in reality.

kubbie wrote:

I'm from Florida, hot and humid. Just got back from a mountain trip to North Carolina, 20 degrees cooler and no where near the humidity.
I always have a small amount of condensation on the lower right corner whenever its cool out.

But this trip as soon as I fired up the bike it fogged up instantly and took a couple hours to clear.

The idea I had was that it doesn't need more vent holes.... it needs a vacuum to draw the moisture out. But how to accomplish this on a bike?

Then it hit me. Use a line coming from one of the intake vacuum ports! That and a small valve petcock valve. In theory it can suck the air (and moisture with it) out. Hopefully it would only need to be run a few minutes. The valve would be to keep gas vapor from flowing up into the speedo when bike is off.

Haven't done it yet... just an idea bouncing round in my head.

This was suggested in that thread on the other site that was referenced on the first page. I raised a concern that introducing a passage between the intake manifold and the dash would upset the pressure comparison between those two spots that the ECU uses to set engine parameters. But if it were a small passage and only open for a short time it wouldn't make much difference I suppose.

If you do this, you should take advantage of one or both of the ventilation tubing guides that Guzzi provided in the bracket that holds the dash. The guides are right below the original baffled vents of the first-generation dash. Finding these was not quite like finding the Lost Ark in the Indiana Jones movie, but it was pretty exciting: The Guzzi engineers were planning a tubing-based ventilation system that was later abandoned!

Here is a photo showing my own ventilation tubes passing through those abandoned guides:

[You must be registered and logged in to see this image.]

Matias wrote:

Hi,
Thanks Moto. Thanks to all.
To reply to your question Moto, no, my new dash as not failed yet. It would be great if the manufacturer would have decided to coat the circuit board like you did, but I doubt it...Anyway, even with the circuits protected, that fog over the instruments is anoying enough...
Once those humid days come I will report how did it go with the sílica bags

Hi everybody.
I just want to make an update on this issue.
After the first 2 weeks of heavy rain here in Portugal (the air get's really humid...you feel the wooden doors swelling at home...) I took the bike out for a ride in a sunny, and relatively chilly, Sunday morning.
I couldn't see any signs of condensation clouds forming in the dash "glass"...
So, for someone like me that parks the bike in the garage and usually doesn't ride under the rain, the dessicant bag and the plastic cover might be a good solution...

sounds like Gore-Tex or the like - gas permeable

Can anyone tell me how to safely remove the instrument cluster for replacement? Is it ttue I cant replace the cluster because of the ECU inside my bike, and the keys sensors.? My cluster failed wom time ago because of the sun. I bought a new one with the hope of simply replacing. Plug and play.

Yes, just replace it. The new dash will ask you to insert a new user code. It will work if you don't but it will keep asking you to do it every start up if you don't.

If your dash is sun damaged it can probably be repaired.

Oh, and as to how you replace it? Undo the mounting screws at the bottom of the binnacle and the screws that hold the surround on at the front and the three at the back of the binnaclethat hold the frame in place. The connector can then be un-snapped from the dash unit and it can be swapped.

If you send the damaged one to me I can see if the woman who fixes them locally can sort it out.

Thank you for your advice. I replaced it following your indications. Works well. Illl test my GRiSO on the street today. [You must be registered and logged in to see this image.]

I think the damaged one will go to the garbage because I live prety far away from australia. I didnt find anyone who could repair mine.

Please don't throw it away. They are an expensive item and one that may soon go out of production.

Is the LCD functioning at all? If so and you have two keys you can re-set the user code to five zeroes and it will be a useful spare for someone. If you want to send it to me I'll cover the postage.

The LCD is almost completely black. OK, I'll try to repair it.