Speedometer not working

[Joe E Licketto]

Way too many posts with "speedometer issue/problem" in the title or body of the threads. So unfortunately I'm going to open a new post for this type of problem. If there is an existing post and someone can point me to one or more that may help answer my question, please save everyone time and point me to the revelavent post(s)

I'm currently having a problem with a customer's 2007 Mastiff. Everything works but the speedometer. I've checked and replaced a defective speedometer sensor (the epoxy sealer appears melted and the replacement looks smooth and fine). Pulled the speed-o and checked for broken wires - none found.

So now I probably could use some more enlightened assistance. Any additional info on areas to inspect or how to check the correct circuits for continuity to/from the speed-o would be appreciated.

Thanks in advance.

 

[Mr. Wright]

With 50 g's of vibration at the handle bars, it's not uncommon for the old mechanical speedos to shake apart. Jack up the bike so you can spin the rear wheel. Unplug the speedo, turn the key on and spin the rear tire. If you can get a reading 0 then 5 then 0 then 5volts, your speedo has gone bad. replace it with a Dakota Digital.

 

[Joe E Licketto]

There are three (3) wires at the speedometer - Black, Green & Red. Please clarify which circuit(s) I'll be checking for voltage, as I do NOT wish to nuke either controller box during testing.

Thanks.

 

[KaptinAmerika]

Red is 12v power, green is your signal, black is your ground

 

[Joe E Licketto]

Now that I've confirmed that the problem most likely is the speedometer (Got a 5v pulse between between the Black & Green wires), which Dakota Digital is the best replacement for the Big Dog OEM speed-o ??

Need to locate one through Drag, Tucker or DD direct for my customer.

Thanks.

 

[Joe E Licketto]

Found Drag Specialties #2210-0149 for red LED & #2210-0148 for Blue LED

 

[roadie1389]

There is a Big Dog specific replacement, BD-140 is the blue and BD-140-R is the red, that already has the JST and a default pulse count set. I have not gotten one yet but folks say the blue is easier to see in the sunlight.

 

[Brent Herridge]

I've also seen many of these threads because......you guessed it.....my speedo works only about 1/4 of the time.

My quandry:

1. $500 is crazy expensive for this thing
2. Other components in the gauge cluster are still working - but will they keep on ? Are they historically more long-lived than the speedo ?
3. I hate digital readouts. I like analog and want to keep it.

What's the longest anyone has seen the DD work after the replacement ?

Has anybody replaced the whole thing with Dakota's other 3 3/8" gauges that include all the features of the original, but in a single package ?

 

[Th3InfamousI]

I've also seen many of these threads because......you guessed it.....my speedo works only about 1/4 of the time.

My quandry:

1. $500 is crazy expensive for this thing
2. Other components in the gauge cluster are still working - but will they keep on ? Are they historically more long-lived than the speedo ?
3. I hate digital readouts. I like analog and want to keep it.

What's the longest anyone has seen the DD work after the replacement ?

Has anybody replaced the whole thing with Dakota's other 3 3/8" gauges that include all the features of the original, but in a single package ?

$500? The speedo is only like $250 and drops in and I haven't heard any of any failures unless someone's bike is overcharging and may fry it with 20+ volts

Sent from my 2PS64 using Tapatalk

 

[old dog]

Low voltage from the battery while cranking can cause the speedometer,and only the speedometer not to function.It can be intermittent depending on the voltage. Try jumping the bike to keep the volts up and see if it works then.

 

[fomanh]

Is the speedometer a sealed unit? I don’t see how to get to the circuit board.

 

[Jwooky]

Its a real pain, but you can get them open.

You have to slowly pry the chrome ring off. I used a fiber stick and went around and around it, many times prying the ring away from the housing a tiny bit at a time

 

[Jwooky]

I've also seen many of these threads because......you guessed it.....my speedo works only about 1/4 of the time.

My quandry:

1. $500 is crazy expensive for this thing
2. Other components in the gauge cluster are still working - but will they keep on ? Are they historically more long-lived than the speedo ?
3. I hate digital readouts. I like analog and want to keep it.

What's the longest anyone has seen the DD work after the replacement ?

Has anybody replaced the whole thing with Dakota's other 3 3/8" gauges that include all the features of the original, but in a single package ?

There are analog versions available. (www.wildsteedworx.com ). I don't like the digital either reminds me of the 80's cars.

The "other components" are not part of the speedo, rather the tach ring.

There was an all in one replacement made by Medallion found on the Late Bulldogs etc, but they are no longer making them.

 

[fomanh]

There are analog versions available. (www.wildsteedworx.com ). I don't like the digital either reminds me of the 80's cars.

The "other components" are not part of the speedo, rather the tach ring.

There was an all in one replacement made by Medallion found on the Late Bulldogs etc, but they are no longer making them.

Thanks. This one has worked intermittently since I got caught in a rain storm last fall. I was hoping to find a lose wire but they all look good. I put it back together and it still work. Seems like once it warms up or once I stop and restart is when it quits working. Even when quits working.... it will jump up to speed and then back to zero. Probably the start toall the wiring gremlins these things are known for.