Digital Speedometer Speed Sensor Conversion

[whitleyjacob]

Hey guys,

I recently purchased a 1981 CB750F that came with an aftermarket speedometer included (Acewell MD52).
I personally do not like the style of the Acewell, so I am swapping it with this one:
https://www.amazon.com/KIMISS-Motorcycle-Instrument-Waterproof-Speedometer/dp/B09HBVP1MB/ref=sr_1_8?crid=1X5PAXWLF4WNB&keywords=kimiss+speedometer&qid=1706801546&sprefix=kimiss+speedomete%2Caps%2C176&sr=8-8

The last owner installed a cable which converts the factory speedometer cable to a digital sensor, but it only has two wires coming from it, which is a Speed Signal (+), and a ground wire. Here is the wiring diagram for the MD52 speed sensor:

Here is the cable I'm referring to:
https://www.dimecitycycles.com/acew...-conversion-cable-for-honda-cb-cl-yamaha.html

The new speedometer I want to swap to uses three wires for the speed sensor:
Speed sensor positive pole, speed sensor negative pole, and speed sensor signal
Here is the connector for the 3-wire sensor:

Is there any way I can convert the 2-wire connector to use on my new speedometer?

 

[brettp]

Can you get a better pic of the second one?

 

[whitleyjacob]

Can you get a better pic of the second one?

The yellow wire (left) is Speed Sensor Positive Pole, Green (middle) wire is Speed Sensor Negative Pole, and Black (right) wire is Speed Sensor Signal.

 

[Loose Chain]

Why don't you just wire it the way the manufacturer says to do it? The new one should have a harness with it.

 

[whitleyjacob]

Why don't you just wire it the way the manufacturer says to do it? The new one should have a harness with it.

I'd like to use the bike's factory speed sensor, which the converter from dimecitycycles utilizes. But they only sell a two wire version made specifically for Acewell speedometers

 

[Loose Chain]

An '81 CB750 doesn't have a speed sensor. You will need a speed sensor made by the same company that builds the tach you want to use. In other words you can't use the Acewell speed sensor on your Kimiss unit. You will need a Kimiss speed sensor.

 

[whitleyjacob]

An '81 CB750 doesn't have a speed sensor. You will need a speed sensor made by the same company that builds the tach you want to use. In other words you can't use the Acewell speed sensor on your Kimiss unit. You will need a Kimiss speed sensor.

The CB750 used a cable driven speedometer. The original analog cable has since been converted to a digital signal using the converter mentioned in my original post. But the converter uses 2 wires, not 3 wires. I'm just looking for help to see if I can use the converter with my new speedometer. Thanks!

 

[Loose Chain]

The CB750 used a cable driven speedometer. The original analog cable has since been converted to a digital signal using the converter mentioned in my original post. But the converter uses 2 wires, not 3 wires. I'm just looking for help to see if I can use the converter with my new speedometer. Thanks!

Your kidding. A CB750 used a cable?

 

[Loose Chain]

I'm trying to answer your question. Like I said, you can't use the Acewell unit. You need to get a convertor for a Kimiss speedo. Was I not clear on that? I'll try it another way. Get a three wire convertor that is compatible with the brand of tach you plan to use.

 

[brettp]

I think you need to remove the old cable converter, then buy a speedo cable conversion specifically your new speedo. All done. It is impossible (unless someone had experience with it) to know how to wire the three existing cables into the two wire set up without knowing what all three of those wires are for specifically.

 

[Loose Chain]

I'm trying Brett but I'm not sure I'm getting anywhere.

 

[Biebs]

This is for a speedo not a tach.
looks like the unit supplied a magnetic sensor you would mount on the wheel and a magnetic pickup.
try that first.

 

[Loose Chain]

This is for a speedo not a tach.
looks like the unit supplied a magnetic sensor you would mount on the wheel and a magnetic pickup.
try that first.

Ya I know, I said the wrong gauge. We have already told him what he needs to do, but thanks.

 

[whitleyjacob]

Ya I know, I said the wrong gauge. We have already told him what he needs to do, but thanks.

This entire thread's purpose is to rewire the two wires into my new three wire speedometer speed sensor. They do not make a three wire version of the converter that my bike currently uses. If you are not providing helpful feedback aimed towards this thread's purpose, please stop responding. You do not understand the situation, and I have tried to make it as clear as possible.

 

[brettp]

I hope you get it figured it out. You'll need to hear from somebody with knowledge of both setups, which you may know. I think it will be hard to find, but you never know.

 

[Loose Chain]

. You do not understand the situation, and I have tried to make it as clear as possible.

You are kidding me, right? I am trying to help you. Has it ever occurred to you that maybe it can't be done? Why the hell you are trying to put that ridiculous setup on one of these bikes is what has me stumped. Why don't you do your homework BEFORE you buy stuff like this instead of giving people $hit for not giving you the answers you want. Get a life a$$hole.

 

[whitleyjacob]

You are kidding me, right? I am trying to help you. Has it ever occurred to you that maybe it can't be done? Why the hell you are trying to put that ridiculous setup on one of these bikes is what has me stumped. Why don't you do your homework BEFORE you buy stuff like this instead of giving people $hit for not giving you the answers you want. Get a life a$$hole.

I didn't purchase the converter man. Please read the original post. You are wasting both of our time, please go elsewhere. I am being very reasonable, you are just not comprehending what I am trying to do, and that's not my fault. Sorry brother.

 

[Loose Chain]

I know exactly what you are doing. You are the one that can't comprehend. I have 52 years under my belt of dealing with people that don't know what the hell they are doing. You can't fix stupid.

 

[Loose Chain]

You didn't look very hard. I found all kinds of 3 wire speedo sensors for motorcycles.

 

[Loose Chain]

Doesn't your kit come with this? That is the sensor. Easy to make that work. You could even run this off the back wheel if you like.