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Posted By: Mark Z GPS speedometer road test - 05/27/20 8:19 pm
I've taken two rides with the speedometer installed, and it seems to be working, except that it's having location-dependent problems acquiring a signal. Also, it's telling me I'm going slower than I think I am, like when it says 60 I feel like I'm doing 70. I guess the next step is to get paced by another vehicle.
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This may not be the ideal location for the antenna (under the steering damper anchor plate). All I can glean from the documentation, which is just a few crude drawings and a bunch of Chinese writing, is that the antenna should be mounted horizontally, right side up. But perhaps it needs to be more exposed. I'll try it like this for a while, as the research continues.
[Linked Image from i.postimg.cc]
Now I just need to paint the bracket and tidy up. I may paint the back of the gauge black, and remove the threaded studs that are for panel mounting. And I need to find a place to hide all that antenna wire, now coiled under the left handlebar (visible in first photo).
[Linked Image from i.postimg.cc]
Posted By: Allan G Re: GPS speedometer road test - 05/27/20 10:44 pm
You are the king of tech on these old bikes Mark!

I wonder if that wire is shielded? The one with the little brass fittings will be, they are often used for carrying a digital signal but can also break easily, some DAB radios use them but they are also used on highly sensitive electronics for carrying a voltage or a feedback signal. The other wire might benefit from being shortened if this is possible, if there is any interference the coil of wire won’t help it. For the antenna could you put a hole in the headlight “ear” and screw the antenna through that?
Posted By: Mark Z Re: GPS speedometer road test - 05/28/20 12:28 am
Originally Posted by Allan G
You are the king of tech on these old bikes Mark!

I wonder if that wire is shielded? The one with the little brass fittings will be, they are often used for carrying a digital signal but can also break easily, some DAB radios use them but they are also used on highly sensitive electronics for carrying a voltage or a feedback signal. The other wire might benefit from being shortened if this is possible, if there is any interference the coil of wire won’t help it. For the antenna could you put a hole in the headlight “ear” and screw the antenna through that?

Oh, I don't know about that... the electronic tach and the LED headlamp didn't work out so well!

Yes, the antenna wire is the one attached with the brass mini coax connector, so I would assume it's shielded. The wire also feels very sturdy. One thing the instructions DO say in Chinglish is "not to cut antenna wire". (By the way, it's three meters long.) But maybe it should be strung out instead of coiled up. I guess I would go back and forth a couple of times under the fuel tank or something like that. I wanted to do some testing before going to the trouble of pulling the fuel tank.

Another thing I was able to glean from the instructions is that the antenna should be mounted horizontally. So off the headlight ear would be awkward. Maybe a bracket off one of the windshield mounts.
Posted By: DavidP Re: GPS speedometer road test - 05/28/20 4:19 am
"location dependent problems acquiring a signal"
Sounds like my GPS. For some reason in the middle of nowhere, clear sky with no obstructions it thinks I'm driving through the middle of a field. Keeps telling me to take turns which don't exist. Anyone considering a self-driving car has never been told to turn right off the side of a mountain by his GPS.
Looks like a nice installation. Keep us posted on how well it works.
Posted By: triton thrasher Re: GPS speedometer road test - 05/28/20 7:37 am
Originally Posted by Mark Z
[Linked Image from i.postimg.cc]

Did you mount your TV satellite dish under your house, facing the ground?
Posted By: koncretekid Re: GPS speedometer road test - 05/28/20 10:37 pm
Mark,
I'd like to see more detail in your mounting bracket, as I have purchased a similar unit. Looks like some kind of compressive band over a rubber band of some kind.
Tom
Posted By: Mark Z Re: GPS speedometer road test - 05/29/20 12:14 am
Tom, here's a link to the product on amazon, which I ordered separately from the speedometer: Fits any 3 3/8"-diameter gauge.

https://www.amazon.com/Auto-Meter-3...d=1590710578&s=automotive&sr=1-2

The available space is so limited that I eliminated the black part of the supplied bracket and just used the clamping ring and the spacer.

They also have a cup, in black or chrome, that encloses the gauge, but it didn't look like I'd have room for that behind my windshield. After engineering-in this bracket, I can see that the "cup" would not allow the gauge to tilt back.
Posted By: Mark Z Re: GPS speedometer road test - 05/29/20 12:20 am
Tom, another thought on this: If you have the facility to cut a 3 3/8"-diameter hole in a piece of sheet metal, a panel mount is simpler. I don't have the tooling to make such a panel; that's why I went for the clamp mount.

By the way, what sort of device did you purchase?
Posted By: Mark Z Re: GPS speedometer road test - 05/29/20 12:22 am
Originally Posted by triton thrasher
Did you mount your TV satellite dish under your house, facing the ground?

I have cable TV.
Posted By: Mark Z Re: GPS speedometer road test - 05/29/20 1:20 am
Originally Posted by triton thrasher
Did you mount your TV satellite dish under your house, facing the ground?

And here's a link to the gauge I purchased:
https://www.amazon.com/gp/product/B074J9MFQV/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

Note in the description it says, "Mount the sensor at any position, on or under the dashboard." Under the dashboard would be pretty "buried" I wager.
Posted By: quinten Re: GPS speedometer road test - 05/29/20 2:08 am
if its mounted upside down , or shielded by metal ...
see install page , best signal reception may be shielded
It may be getting a nice signal reflected off the pavement and all good ?
if your not happy with the reception ... point it at the sky
[Linked Image from images-na.ssl-images-amazon.com]
Posted By: koncretekid Re: GPS speedometer road test - 05/29/20 12:14 pm
Mark,
I bought the same unit as yours except mine reads in KPH which is a bit handier in Canada. I'm thinking about mounting the sensor behind the seat, possibly with industrial Velcro so as not to have to drill a hole. I haven't tried it yet but I will be making a mounting bracket as you suggest with the 3-3/8" hole. I have a mill-drill with a turn table so I'll be able to cut the hole to size.
Tom
Posted By: triton thrasher Re: GPS speedometer road test - 05/29/20 6:50 pm
Originally Posted by Mark Z
Originally Posted by triton thrasher
Did you mount your TV satellite dish under your house, facing the ground?

I have cable TV.

I was in Barbados once and there was cable radio. First thing in the morning, they read out a list of people who had died.
Posted By: Hillbilly bike Re: GPS speedometer road test - 05/29/20 8:37 pm
My friend has an Australian made GPS speedo on a Triumph and a Guzzi. They have a magnetic small round pod connected by a thin cable to the speedo. I notice he sticks the magnet on the fuel tank after trying more concealed locations.
Posted By: koncretekid Re: GPS speedometer road test - 05/29/20 11:08 pm
I made an aluminum plate mounting for mine today and mounted the sensor just behind the seat using industrial Velcro.

[Linked Image from i.postimg.cc]

It looks quite "industrial" to me so I'll narrow it up.

[Linked Image from i.postimg.cc]

I took it out for a 10km run and it seems to work perfectly. Time will tell how it holds up on a B44.

Tom
Posted By: koncretekid Re: GPS speedometer road test - 05/30/20 4:07 pm
I removed the bracket and flattened it and re-positioned it back in the milling machine and removed 1/4" off each side and the outer radius.

[Linked Image from i.postimg.cc]

I then re-bent it, sanded it lightly, and painted it satin black. Re-mounted on the bike.

[Linked Image from i.postimg.cc]
Posted By: Mark Z Re: GPS speedometer road test - 05/31/20 12:28 am
Tom, very nice! I was almost going to ask you if you would be interested in making one for me, but then I took another look and realized it would not work on my bike because of the steering damper knob. I guess I'm committed to the bracket I have, due to the lack of space. I have a windshield too which I plan to put back on, and which also limits the available space; I removed it to make it easier to work on the speedo.

I'll definitely be moving the antenna. The rear fender idea is kind of cool, but in my case it would be under a luggage rack and tour bag. I might Velcro it to the headlamp shell or to one of the windshield brackets for further testing. I'm joining in a small group ride tomorrow evening, which will be a good opportunity to get paced.

Tom, what's your plan for hiding the extra 3 meters of antenna wire?
Posted By: Mark Z Re: GPS speedometer road test - 05/31/20 12:43 am
Originally Posted by quinten
if its mounted upside down , or shielded by metal ...
see install page , best signal reception may be shielded
It may be getting a nice signal reflected off the pavement and all good ?
if your not happy with the reception ... point it at the sky

Yes, that's the sheet I got with the gauge, all except for the English text at the top. Are those your words, or a translation of something on the sheet? Yes, I got that it wants to be on plastic. I wonder, if I Velcro it to the headlamp shell, will the Velcro keep the metal headlamp shell from "shielding the reception"? Guess I'll find out tomorrow...
Posted By: robcurrie Re: GPS speedometer road test - 05/31/20 6:21 am
You could 'bury' it in the foam of the seat, behind where you sit if you want it hidden.
Rob C
Posted By: koncretekid Re: GPS speedometer road test - 05/31/20 12:08 pm
My antenna lead was 4.9m long, or 16 feet. Who on earth need a 16 foot long antenna lead? In any case, I started at the rear fender location and threaded the lead up to the steering head, back to the seat area, and again, and again until I finally got to the instrument at the front. The lead is then zip tied to the top frame tube in several places. The only place it's visible is at the steering head, where there are lots of wires to choose from.

[Linked Image from i.postimg.cc]

The overall appearance

[Linked Image from i.postimg.cc]

Tom
Posted By: konon Re: GPS speedometer road test - 05/31/20 12:53 pm
Nice bike Tom , got to be fun.
Posted By: Mark Z Re: GPS speedometer road test - 06/01/20 1:30 am
Originally Posted by koncretekid
My antenna lead was 4.9m long, or 16 feet. Who on earth need a 16 foot long antenna lead? In any case, I started at the rear fender location and threaded the lead up to the steering head, back to the seat area, and again, and again until I finally got to the instrument at the front. The lead is then zip tied to the top frame tube in several places. The only place it's visible is at the steering head, where there are lots of wires to choose from.
Tom

Yeah, that looks like fun! That's pretty much what I was thinking with the wire, going back and forth a few times under the fuel tank.

However... I Velcro'd the sensor to the top of my headlamp shell and went for another ride today, and got equally unsatisfactory results - no reception at all on my road, and it lost signal in a couple of places on the highway - I think the same places it lost signal before. Maybe because the sensor is on a bit of a slant to the side? I wonder if having the antenna wire coiled up is a problem?
Posted By: triton thrasher Re: GPS speedometer road test - 06/01/20 5:52 am
Is your ignition suppressed?
Posted By: quinten Re: GPS speedometer road test - 06/01/20 6:14 am
[
ouch ,
Posted By: quinten Re: GPS speedometer road test - 06/01/20 6:23 am
the gps apps on my android semi-smart phone
have a tab the tells me how many satellites are available
and how many it is locked onto .
Typically it locks onto 10 to 15 satellites out of 31 that are in obit .
it take a minimum of 4 to get " triangulation "

i dont suppose your speedo has this kind of extra data logging ... but you can use
any smart phone to check gps capabilities .
( gps works best with broad Horizon
and it's worse in deep valleys )
Posted By: Mark Z Re: GPS speedometer road test - 06/02/20 4:06 am
Originally Posted by triton thrasher
Is your ignition suppressed?

No, but the speedo has dedicated power wiring directly to the battery (via the main fuse and its own power switch), and none of the wiring is near the HT circuit. I know, that doesn't guarantee no RF noise, but I'll try to address antenna and antenna wire location first.

FWIW, I don't get cell phone reception at my house. OTOH, the Garmin GPS unit I have for my car (truck) seems to get reception everywhere, and that doesn't even have an external antenna. (However, for all I know, the Garmin may make use of the automobile's wiring or body.)

Tom, please let us know how your speedo tests!
Posted By: robcurrie Re: GPS speedometer road test - 06/02/20 5:56 am
Mobile phones use ground based antennas vs GPS Satellites. As I mentioned previously I have experienced poor reception with my speedo on heavily overcast days.

Rob C
Posted By: Mark Z Re: GPS speedometer road test - 06/02/20 3:43 pm
Originally Posted by robcurrie
Mobile phones use ground based antennas vs GPS Satellites. Rob C

Doh! I knew that, but forgot.
Posted By: koncretekid Re: GPS speedometer road test - 06/02/20 8:18 pm
Love to, Mark, but the B44 is not yet titled or registered because the DMV is shut down and I can't complete my application for "reconstructed vehicle".
Posted By: Mark Z Re: GPS speedometer road test - 06/02/20 9:36 pm
Originally Posted by koncretekid
Love to, Mark, but the B44 is not yet titled or registered because the DMV is shut down and I can't complete my application for "reconstructed vehicle".

Ok, whenever; I'm in no hurry either. Right now I have lawn tractor issues (the shop can't seem to get me the right flippin' drive belt) and an acre of out-of-control lawn that I'm trying to contain with a 20-inch rotary "pusher".
Posted By: quinten Re: GPS speedometer road test - 06/03/20 12:50 am
Originally Posted by Mark Z
Originally Posted by robcurrie
Mobile phones use ground based antennas vs GPS Satellites. Rob C

Doh! I knew that, but forgot.

used the GPS chip on a smartphone just yesterday ... for fun . ( the phone has no sim-card to receive cellular service)
while flying from maui to the mainland .
Definitely not any cell towers in the area .
Your smartphone has a GPS chip ... different functions determine
Whether real GPS is used ... or assisted GPS ( cell towers )

Satellite reception on one GPS app. ... averaged 11 satellites locked in .
39,000 ft and 539 mph .

a separate GPS "compass program" locked on to 8 to 15 satellites at any one time .

I use the pure GPS function often... when mountain biking in the woods ... well out past cell reception .
works great as a bicycle speedometer ... and helps me get home on the those occasions when I get lost .
Posted By: Mark Z Re: GPS speedometer road test - 06/03/20 3:25 pm
Sometimes I think I may be the only one left on the planet with a "dumb phone" (one of the reasons I dismissed the phone app solution in favor of the dedicated speedometer). So the comparison with MY cell phone reception is still unfounded.

But the comparison with YOUR cell phone is interesting, if it gets reception "mountain biking in the woods". And I assume there is no external antenna.

So the investigation at hand is still, what kind of reception I should expect from this device, given optimum antenna mounting and wire routing. It occurred to me that if it proves to be intermittent at best, the odometer function will be virtually useless.
Posted By: Mark Z Re: GPS speedometer road test - 06/09/20 5:39 am
So now I mounted the antenna on a plastic bracket attached to the windshield. Reception is still spotty. I can't imagine a better location for the antenna, but I haven't yet uncoiled he antenna wire. That will be my next and possibly last test.

[Linked Image from i.postimg.cc]
Posted By: Mark Z Re: GPS speedometer road test - Update - 06/12/20 2:51 am
I finally got satisfactory results this evening - it was the coiled up antenna wire. I had first moved the antenna a couple of times, finally to a plastic bracket off the windshield, to no avail. But for this last test, I uncoiled the antenna wire and ran it back, doubled, under the tank and along the frame all the way back to the luggage rack. Now I get reception everywhere, even in my back yard, and there were no signal interruptions during today's test run.

I'm ready now to cut the extra studs off the back of the speedometer, paint it and my bracket black, and pretty-up the wiring. Oh, and wire the speedometer backlighting. I didn't do that because I don't want the complication of going through the lighting switch; however, I don't see the problem of having the gauge lit whenever it's on (it has its own switch); that is, I doubt that the backlighting draws more than a couple hundred milliamps. And, in NYS, the headlight must be on at all times, so the gauge would always be lit anyway.
When I first took delivery of a GPS speedo like that, I was doubtful that it would really work, so I connected it to a battery and ran across the garden with it.

On the bike, it used to “crash” and return to zero mph, until I fitted a suppressor spark plug cap.

Then recently it started the crashing to zero again. Turns out the HT side of the ignition coil was failing, going open circuit. In about 70 miles, the bike went from an occasional misfire, to crazy spluttering and banging.

You’re right the illumination draws very little current. Mine comes on with the ignition.
Posted By: MarcB Re: GPS speedometer road test - Update - 06/12/20 8:17 pm
Originally Posted by triton thrasher
On the bike, it used to “crash” and return to zero mph, until I fitted a suppressor spark plug cap.

Then recently it started the crashing to zero again. Turns out the HT side of the ignition coil was failing, going open circuit. In about 70 miles, the bike went from an occasional misfire, to crazy spluttering and banging.
Interesting. It could almost serve as a crude onboard diagnostic smile
Posted By: Mark Z Re: GPS speedometer road test - Update - 06/13/20 4:33 am
Originally Posted by triton thrasher
When I first took delivery of a GPS speedo like that, I was doubtful that it would really work, so I connected it to a battery and ran across the garden with it.

On the bike, it used to “crash” and return to zero mph, until I fitted a suppressor spark plug cap.

Then recently it started the crashing to zero again. Turns out the HT side of the ignition coil was failing, going open circuit. In about 70 miles, the bike went from an occasional misfire, to crazy spluttering and banging.

You’re right the illumination draws very little current. Mine comes on with the ignition.

You didn't say how the foot race trial went. How fast did you run?

When my speedo went to zero in previous tests, I assumed it was because it lost reception. In those cases, I think it resumed after turning it off and back on. (I say "I think" because it's hard to constantly observe the gauge AND drive!) I'll continue to observe and see if I might need to try suppressor caps.

One other weird thing happened: The odometer reset itself to 0 after reaching somewhere around 68-70 miles.
I ran fast enough, far enough to make the needle move and probably to confirm the neighbours’ opinions on my state of mind.

I actually have a switch on the handlebar for switching power to the speedo off and on again when it misbehaves. It’s still less trouble than trying to keep an original speedo and its drive working.
Posted By: Mark Z Re: GPS speedometer road test - Update - 06/14/20 9:02 pm
Originally Posted by triton thrasher
I actually have a switch on the handlebar for switching power to the speedo off and on again when it misbehaves. It’s still less trouble than trying to keep an original speedo and its drive working.

Yes, I put a little push on/push off switch on the mounting bracket. (You can see it in the above photo, to the right of the gauge.) Correct, beats the tar out of a mechanical gauge.

I took a 55-mile ride today, and at no time did the speedo "crash". I like it!
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