My speedo's full of water...resolved with pictures.

[paddy]

I've had a niggling problem since I bought my DR. Water seems into the trip computer (TC) and then condensates on the inside of the window making it almost impossible to see. I had tried to seal it a bit better with silicone, but alas to no avail. I was really just ignoring the problem until I went for a blat down Muriwai beach (see the thread Muriwai Ride Tonight). There was quite a lot of salt water sloshed around and I think quite a bit of it got into my TC. The speedo still worked, but the odometer and clock stopped working so well. Funny that. Real annoying when you don't know when you need to fill up. Anyway, I thought I would post the repair process. I don't have a lot of time, so I might do it across a bunch of posts. Think of it as a RR, but more like a project report. I haven't ever attached photos to a forum post before, so we'll see how this goes.

[paddy]

The first picture is the TC housing. You can see the old silicone that I had to break around the rim (that's a real pain - I wouldn't ever recommend sealing anything with silicone, it shrinks over time and leaks, and if the seal isn't perfect and you need to redo it - it's hard to break, and even harder to clean off). You can also just see the water. It's more obvious in the next few photos. I gave it a real good hosing off when I got home in the home of displacing as much salt as possible as I knew I wouldn't be able to open it and do it properly until the weekend some 5 days later.

[paddy]

The first time round I hadn't stripped out the buttons as it involved breaking two plastic rivets that then can't be replaced, but it is a likely source of the leak (or one of the leaks) so this time I went ahead and did it. There was quite a lot of water under the seal so it was probably a good call.

[paddy]

The rubber cable grommet at the rear was also a very likely source of water ingress. It had quite a lot of water around it. You can see the PCB where the cable comes in is quite corroded.

[paddy]

The is a large plastic cover over the LCD panel. The panel is glass and sits on top of two pinkish foam blocks. The display is backlit with six orange LEDs. It turns out that the pressure that the cover was putting on the LCD was masking a dry joint, but I will get to that later. (What looks like damage on the LCD is just an artefact of the camera lens probably from the sun coming in the window behind me.)

[paddy]

I had some PCB cleaner that had been hanging around for a long time. I emptied that every where (you can buy this stuff at Jaycar electronics). There wasn't much left and I needed something else. Ideally I would have used isopropyl alcohol, but that is actually getting harder and harder to get - the chemist can supply small and expensive quantities, but even they didn't have any. (I believe BOC gasses will supply larger quantities.) Eventually I settled on acetone (well, actually it was nail polish remover - it had acetone in it amongst other things). That seemed to do the trick although I did try to avoid the LCD panel. I made sure to slosh plenty over the buttons to clear out any water that might have gotten into them.

[paddy]

This is what happens when you wife figures out why you are taking pictures of what you are doing and declares that "clearly you need to be in the pictures to". The second one is my, great-just-what-I-wanted-I-always-look-like-a-dork-in-pictures face.

[paddy]

Next we need to think about how to re-seal this thing. Off to the hardware store. Nothing. Fall back to repco. Bingo. Lots of stuff for making gaskets. This sounds promising, so I grab a tube of Gasket Goo. It claims to set solid and yet be separateable. Better still, it's only $10 for the tube (which might sound like a lot for a small tube until you see the sort of prices for this kind of stuff).

[paddy]

I couldn't resist opening it up to see what it was like. Okay...I really wanted to know what colour it was. It's black. I think there must have been a compressed air bubble in it somewhere because it pored out. And kept poring out. I gave it a squeeze to eject some and reduce the pressure. It still kept coming. Oh well, we'll get to see how long it takes to dry.

[paddy]

I also removed the cable mounting from the plastic housing. It's just a little metal wheel with a hall effect sensor mounted on a little bracket. Why this is in the wheel rather than having a cable I don't know. I guess that this way they can use the same wheel tooling for both the analogue and digital speedometer models.

[paddy]

The cables entering the TC were originally sleeved in a black rubbery/PVC-ish pipe (I'm not really a plastics engineer - it was black and it was plastic). It was quite loose around the cable and it struck me as a likely water entry point. I really wanted to re-sleeve the whole thing. The problem is that any heatshrink that will fit over the connector isn't going to be tight on the cable and is going to be just as bad. Eventually, I decided to bite the bullet and de-solder the cable end from the board. All I can say is what a mission.

There are two cables coming in. All of the ends are terminated into crimp on pins. The pins are then mounted in a plastic carrier (at the bottom of the first photo). Then all of the pins are soldered onto the PCB. The board is through plated which means you end up needing a whole lot of heat to remove the pins. The problem is that I can't apply enough heat to all of the at the same time. Eventually I resorted to side cutters and hacked the thing of. Then I could remove the pins one by one. It's not very need, but the desoldered board is in the second photo.

[paddy]

I noticed that the second (smaller) cable wasn't actually connected to anything on my bike. I traced the tracks on the PCB and they just disappeared into a large IC. Oh well, work smarter not harder. I threw that one in the rubbish. I can't quite figure out why it needs that many cables. Really. All it does it lights up when the bike is on and display stuff. The speedometer reads through a mechanical cable. To my mind it needs three connections:

+ve 12v continuous (power the clock when the bike is off)
+ve 12v switched (turn on the display and backlight when the bike is on)
gnd (shared ground)

Really, this is way over complicated...

I sleeved the cable in some heatshrink and tinned the ends. The cable was quite corroded along its length so it really didn't tin very well (photo 2). Hopefully this will be okay as I really don't have the tools needed to replace the connected if I were to replace the wires (I would end up needed to replace the bike end to match).

I soldered the cable directly into the board and applied some hot-glue around the cable entry point (on the face side of the PCB - it is really hard to solder through hot glue if this ever needs revisiting) to provide some physical security.

[paddy]

Time for me to hit the sack. The next instalment will be sealing.

[NordieBoy]

This is what happens when you wife figures out why you are taking pictures of what you are doing and declares that "clearly you need to be in the pictures to". The second one is my, great-just-what-I-wanted-I-always-look-like-a-dork-in-pictures face.

Good to see you're using psycology on it :D

[junkmanjoe]

are you sure your allowed to fix it on the dinner table...
my parther would go off the wall mate....
good luck with sorting ya prob out..

[Okey Dokey]

ha-ha. When I saw this thread title I was thinking men's swimsuit-speedos- they shouldn't fill with water! I was curious to see how you drained them! :eek:

good technical stuff, BTW

[Tony W]

are you sure your allowed to fix it on the dinner table...
my parther would go off the wall mate....


So who's the boss when your Mrs is home then....:spanking: :laugh:

[junkmanjoe]

yip under the thumb.

i have noticed lately a lot of dzr400 motards on the roads.

[marks]

feck what a mission

about half way through I'd have been reaching for a hammer

well done

[paddy]

are you sure your allowed to fix it on the dinner table...
my parther would go off the wall mate....
good luck with sorting ya prob out..

Actually, whilst it is our dinner table, it tends to be used more as a "dump stuff that has no other place to live" table. The kids eat at the breakfast bar and we either eat on the couches, or on the edge of the table. Periodically, we clear it off and use it. But that doesn't last long as then there is more space to dump stuff....

I actually got away with saying, "I know you are eating at the DINING table, but would you mind moving and eating somewhere else so I don't get crumbs on my workspace". :-)

[paddy]

ha-ha. When I saw this thread title I was thinking men's swimsuit-speedos- they shouldn't fill with water! I was curious to see how you drained them! :eek:

good technical stuff, BTW

Ahhh...the all important apostrophe!

[paddy]

feck what a mission

about half way through I'd have been reaching for a hammer

well done

It was a bit like that as I had already cleaned it out once and siliconed it shut. I'd really had enough by the time I had managed to get it open again. It took me a while to decide to spend the fiddly time and desolder the cable but eventually I decided to do it. I really didn't want to go through the process again! So far it's been out overnight in one heavy downpour and it's been fine.

I will try and post some more tonight. I'll be heading into the "sealing" phase.

[paddy]

Well, I thought a great way of applying the Gasket Goo would be to use a syringe with an 18 gauge aspican (blunt needle). Why so much detail you might ask. Well, I just wanted to let anyone else, that might have a selection of medical equipment, that Gasket Goo is to thick to such into and 18G aspican. Doh. Never mind. Instead I used the aspican like a paint brush which worked really well. I suspect a toothpick would work equally well. As you can see, I applied a generous layer of Gasket Goo to the sealing surface of the buttons. I also put a layer on the plate that presses the buttons into place. I hope this will increase it's thickness a bit and help to maintain a good seal. I don't think it was leaking, but I also added a small layer on the face of the hall effect sensor's bracket.

[paddy]

Next I remounted the hall effect sensor. I noticed some vent holes that were covered with a semi-permeable cloth. I elected to fill them with hot glue. I will deal with venting my own way. I used Gasket Goo to re-seal the rubber boot, but it tended to pull away from the edges with any deflection so I gave the inside a clean with some acetone and secured it with hot glue. Once the glue was set, I forced a whole bunch more Gasket Goo under the lip from the outside. Hopefully this will do it.

As you can see in the second picture, I put a dog leg into the cable right beside the PCB. This should help to reduce the stress on the less-than-wonderful solder joints.

Oh, and a tip for using hot glue. It is called "hot" glue for a reason. You will get much better adhesion if you are patient and let the gun get really hot. I left mine for about 30 minutes before using it. The temptation is to just squeeze harder rather than waiting.

[paddy]

I decided to vent the until with some clear PVC pipe. I think it's around 4mm pipe from Mitre 10. It serves three purposes. It will allow the unit to breath with temperature and altitude changes, it services to fill up the boot which is considerably larger than the cable passing through it, and in the event that the unit gets condensation in it again, I hope to be able to introduce enough moving air to dry it out quickly.

The 16mm heatshrink that sits over the whole lot is glue lined and so should give a good seal. Oh, and if you are copying me and have the same unit, 16mm heatshrink will not fit over the connector. And yes, I discovered this before I soldered the cable to the board. :-)

You can see the remnants of the Gasket Goo in the second picture. It was a whole lot messier, but I cleaned up the outside with some acetone (just a damp napkin) which worked really well.

In the third photo you can see that I doted some hotglue around the top edge of the boot and between the cable and pipe just to help fill in all of the holes. I also applied a generous quantity around the outside edge of the boot where the heatshrink will sit. I allowed that to cool and then pushed the heatshrink down over it. The heatgun will re-melt the glue as the heatshrink shrinks. I shrank the heatshrink most of the way up and then used hotglue, injected into the end, to shrink the last 7mm or so. This gives a good seal at the far end. You can see the end result in the last photo.

It's worth noting, that while the inside of the boot was sealed with hot glue, and the top of the boot had a substantial quantity of hot glue, the middle did not. In fact I was quite pedantic about cleaning off the excess glue. I want the boot to be able to flex in the middle so that as the cable moves there is not to much stress on the seal into the TC itself.

[junkmanjoe]

yea mate most good ideas to save time, mostly turn to crap.

good on ya for attacking such a task.

hope it stops leaking aye.

yip i understand about your table, i have to move kids stuff, wifes paper work, laptops, just so i can eat my chops.......

[paddy]

Wow, this is starting to look like a job well done... The back plate that the electronics mount to fits inside the front cover (that contains the "window"). I applied a considerable amount of Gasket Goo to the rebated edge and a smaller amount to the back place itself. I was careful to ensure all screw holes were well encircled - I don't want them to leak. (In practice that means they were quite well covered, but oh well, I'm sure they'll come out if I need them too.) I put the cover on loosely at first, allowing the Gasket Goo to dry for 30 minutes before cinching the screws down. I hope this will provide a better seal.

[paddy]

Next I cut off the excess PVC tube. I tried to determine a good length by holding the unit in the bike. I wanted it to be reasonably protected from the elements without getting too carried away. I took the smallest drill in my cheap Warehouse drill kit and whacked a bunch of holes in the end of the PVC pipe. I forced some cotton wool into the pipe so that it covered the holes quite tightly and then topped the whole lot of with some hot glue. There is a recurring pattern here...

(Oh, and I meant to mention this earlier - but yes I know there is inadequate depth of field in quite a few of my photos. I wasn't really paying enough attention.)

[paddy]

As a complete aside, I just found a use for the badly constructed table they made me make in third form wood work (why on earth did I take that). It's the perfect height, holding the front wheel two or three inches off the ground, and the rear around half an inch off the ground.

[paddy]

You can just see the remounted unit (minus a small black wind/wiring shield). It just occurred to me that I haven't taken a picture of the complete and remounted unit. I will try and do that tomorrow in the light. Oh, and if you are wondering about my wonderful waterproof pannier, they are $12.99 at The Warehouse. Add some cables ties, a piece of cardboard to protect the seat, and a $3.99 pack of bungee straps and you have a very cheap, and very waterproof, way of getting your laptop to work.

Best wishes to you all.

[paddy]

Postscript: The seal is working well so far and just survived a decent overnight downpour. I did manage to avoid using the buttons for around 4 days to give the Gasket Goo a good change to set. I am thinking about adding a smaller diameter of glue-lined heatshrink to the PVC pipe. I would shrink it just above the holes to hold it in place, leaving the portion over the holes un-shrunk. It would be a bit like a splash jacket, but still allowing the pipe to breath. You can over-design these things though....

[Tony W]

I have one of these 'speedos' on my DR-Z400SM.

When I change to the 21" front wheel, the Km per Hour reading goes out about 15 percent. Does anyone know how to "get into" these to adjust, to compensate for tyre circumference.

(I am aware of the tripmeter distance compensation feature.)

[paddy]

I have one of these 'speedos' on my DR-Z400SM.

When I change to the 21" front wheel, the Km per Hour reading goes out about 15 percent. Does anyone know how to "get into" these to adjust, to compensate for tyre circumference.

(I am aware of the tripmeter distance compensation feature.)

Hey Tony,

There is a trip-meter distance compensation feature? Tell me more...

Hopefully the pictures above will give you a pretty good idea of how to get into it. There is a thin foam gasket that seals the back of the unit. Mine fell into several pieces, so you will probably need a plan b for re-sealing the unit if you are going to open it.

Everything that I am about to write is working under the assumption that your unit is internally identical to mine (which is on a 1997 DR250). On the back of the main PCB (printed circuit board) you will find a crystal (small elongated silver canister). Somewhere near the crystal you will see a small trim-cap (alterable capacitor). It is probably a reasonable assumption that the crystal and capacitor make up a reference oscillator that the pulses coming from the wheel hall effect sensor are compared to. If you can alter the frequency of the oscillator then you can alter the ratio between the two and therefore affect the speed reading for a given wheel revolutions per minute.

On my unit, the trim-cap was filled with epoxy. If you could somehow break that without destroying the cap then you might be able to adjust it. This has several large assumptions though. Firstly that you can break the epoxy without breaking the capacitor - which is very unlikely, second that you can drive the speedo at a fixed speed (maybe with a power tool) so that you can make a percentage based adjustment, and finally, that the oscillator isn't used for anything else within the trip computer - like the clock for instance (although this is extremely unlikely).

Personally I wouldn't bother; however, if I were going to bother, I would probably replace the cap altogether, or solder another one in parallel with it on the board and use that to make adjustments (indeed if you traced out the circuit, you could calculate the value required for a 14% decrease - which would translate into a 17% required increase in oscillator frequency - then you could simply solder a fixed value cap to the board).

Just for you reference, based on your wheel sizes (18"->21") you would expect your real speed to be 14% less than the value on the speedometer. For example, if the speedometer say 117 km/h then you will actually be travelling at 100 km/h (presuming that the unit was accurate for the 18" wheel).

If this stuff doesn't make sense to you, then I would leave it alone, you are probably going to break it. If it makes sense to you, then, like me, you have probably decided that it definitely isn't worth the effort. If I were you I would stick a GPS and the bike and use that.

Feel free to ask questions though and I will do my best to answer them...

Cheers,
Patrick

[Tony W]

Hey Tony,

There is a trip-meter distance compensation feature? Tell me more...

Hopefully the pictures above will give you a pretty good idea of how to get into it. There is a thin foam gasket that seals the back of the unit. Mine fell into several pieces, so you will probably need a plan b for re-sealing the unit if you are going to open it.

Everything that I am about to write is working under the assumption that your unit is internally identical to mine (which is on a 1997 DR250). On the back of the main PCB (printed circuit board) you will find a crystal (small elongated silver canister). Somewhere near the crystal you will see a small trim-cap (alterable capacitor). It is probably a reasonable assumption that the crystal and capacitor make up a reference oscillator that the pulses coming from the wheel hall effect sensor are compared to. If you can alter the frequency of the oscillator then you can alter the ratio between the two and therefore affect the speed reading for a given wheel revolutions per minute.

On my unit, the trim-cap was filled with epoxy. If you could somehow break that without destroying the cap then you might be able to adjust it. This has several large assumptions though. Firstly that you can break the epoxy without breaking the capacitor - which is very unlikely, second that you can drive the speedo at a fixed speed (maybe with a power tool) so that you can make a percentage based adjustment, and finally, that the oscillator isn't used for anything else within the trip computer - like the clock for instance (although this is extremely unlikely).

Personally I wouldn't bother; however, if I were going to bother, I would probably replace the cap altogether, or solder another one in parallel with it on the board and use that to make adjustments (indeed if you traced out the circuit, you could calculate the value required for a 14% decrease - which would translate into a 17% required increase in oscillator frequency - then you could simply solder a fixed value cap to the board).

Just for you reference, based on your wheel sizes (18"->21") you would expect your real speed to be 14% less than the value on the speedometer. For example, if the speedometer say 117 km/h then you will actually be travelling at 100 km/h (presuming that the unit was accurate for the 18" wheel).

If this stuff doesn't make sense to you, then I would leave it alone, you are probably going to break it. If it makes sense to you, then, like me, you have probably decided that it definitely isn't worth the effort. If I were you I would stick a GPS and the bike and use that.

Feel free to ask questions though and I will do my best to answer them...

Cheers,
Patrick

Thanks for the reply Paddy.:sunny:

A mate had just bought a Vapor brand unit and it was easily adjustable by manipulating buttons on its face.
Wishful thinking made me make this hopeful enquiry !
Leaving well enough alone, is the answer in this case. :yes:
At least the tripmeters are adjustable.(actually 17-21)

Cheers, great effort.
Tony

[paddy]

Thanks for the reply Paddy.:sunny:

A mate had just bought a Vapor brand unit and it was easily adjustable by manipulating buttons on its face.
Wishful thinking made me make this hopeful enquiry !
Leaving well enough alone, is the answer in this case. :yes:
At least the tripmeters are adjustable.(actually 17-21)

Cheers, great effort.
Tony

It is quite possible that there is an undocumented feature to change that. The problem is that I know nothing about the unit other than what I observed internally and what I found out at the following link:

http://www.thumpertalk.com/forum/archive/index.php/t-352333.html

If you know any more I would be quite interested to know...for example, when you said the trip-meters are adjustable - did you just mean with the +/- buttons? It sounds like you are alluding to something a little more (which suggests that you would expect a similar functionality for the speedometer).

[Tony W]

It is quite possible that there is an undocumented feature to change that. The problem is that I know nothing about the unit other than what I observed internally and what I found out at the following link:

http://www.thumpertalk.com/forum/archive/index.php/t-352333.html

If you know any more I would be quite interested to know...for example, when you said the trip-meters are adjustable - did you just mean with the +/- buttons? It sounds like you are alluding to something a little more (which suggests that you would expect a similar functionality for the speedometer).

Yes Paddy.
You can immediately alter your twin tripmeter + or - 30%.
I use this for compensating distance travelled when I change to the larger 21" wheel.

I use 115% for (17" to 21".)

[paddy]

Yes Paddy.
You can immediately alter your twin tripmeter + or - 30%.
I use this for compensating distance travelled when I change to the larger 21" wheel.

I use 115% for (17" to 21".)

Would you mind posting the process for making that adjustment for the benefit of anyone else that searches and finds this thread in the future?

[Tony W]

Would you mind posting the process for making that adjustment for the benefit of anyone else that searches and finds this thread in the future?

A pleasure.

The 4th button along is labelled TRIP/TIME.
Turn on ign key to enable power.
Press and hold down that button for 5 seconds.
One of the two trip displays will change: usually will read '100', as in 100%.
Then use the + or - button to adjust the amount of compensation.
The display has a change range of 70% to 130%.
When adjusted to your requirement, push TRIP/TIME to revert to normal display.

To readjust, repeat this procedure.

This procedure was taken from the handbook.

Cheers.