I want to keep my turn signal auto-cancel feature

[esmith87]

I am wanting to keep my auto-cancel feature of my blinker system when I replace my gauges with a more modern single gauge setup. Does anyone know if its electronically safe to splice the wiring off of the clutch safety switch to replace the reed switch in the odometer? The clutch switch is normally open (NO). I don't have a good grasp on all the current draws on the system (or electrical circuits for that matter), and don't want to fry something important. Any insight is helpful and appreciated. This would affectively cancel my flashers as I'm leaving the turn instead of farther down the road. This can sometimes cause confusion in traffic in congested areas.

 

[BBS360]

It's hard to say what safe is without knowing exactly how you are planning to overcome the loss of the stock reed switch in the speedo.

It varies slightly by model but the wire for the reed switch should go directly from the auto-cancel unit to the reed switch in the stock odometer, then to ground.
The stock reed switch is also normally open but it closes periodically as the speedo cable from the front wheel rotates. Any replacement would need to close and open at the same rate that the stock unit does.
There is probably negligible current through the reed switch.

I'm not clear what you are trying to accomplish with the clutch safety switch or what you plan to replace the stock reed switch with. Does your new gauge replicate the reed switch function?

 

[arfstrom]

Clutch switch has nothing to do with the speedo. Page 29 of a manual I downloaded called "xs400_manual_part3_wheels_brakes_tires_electrical.pdf" has the Reed relay listed. I am going put a TIFF image, here, The previous manual is in the manual section, at the top of the garage.

There is one more decent diagram out there, I have looked for the other relay breakdown, I couldn't find it. I am sure its is on here (this web site) I thought it was in a manual as well as this one.

 

[esmith87]

I was trying to research exactly how that reed switch worked. Couldn't find a clear answer. So does it send more than one signal to the relay during an auto cancel cycle?

 

[BBS360]

It constantly pulses at all times as the front wheel turns.
The auto cancel unit starts counting the pulses when the signals are activated. When enough pulses are counted, the equivalent of around 500', the canceller cancels.

Depending on the new gauge you might be able to install a new reed switch and magnet to activate it. You'd have to somehow attach the magnet to the speedo cable inside the new gauge and mount the reed switch close enough to be activated by it.

 

[esmith87]

@BBS- Thanks! now I understand! I thought the reed switch was being used as a single signal trigger for the cancel unit. If that was the case then I would have just looped my clutch switch circuit and used the switch for the flasher cancel circuit. It appears my understanding was incorrect.

 

[BBS360]

Don't give up hope.
I don't think anyone has bothered to do it before but the new gauge might have enough room inside to retrofit the necessary pieces. Might even be able to transplant the reed switch hardware from the old speedo.

 

[esmith87]

I'll have to figure it out, as I don't have the old speedo anymore. Looks like I'll be doing some hard thinking on how to get this accomplished. Thanks

 

[16VGTIDave]

A reed switch could be mounted on the front fork leg and be triggered by a magnet. Like an electronic bicycle speedometer/odometer.

 

[esmith87]

Will it create the right number of pulses for my auto cancel relay. Seems like it would be awfully fast pulse rate. I was thinking of using the tach cable hole on the motor and making a rotating magnet and a stationary reed pickup, but the heat might be the killer there.

 

[16VGTIDave]

The reed switch is used to measure distance, not engine RPM, so the tach cable drive wouldn't be of any use in this case.

What you need to find out is how many pulses are required for the auto-cancel to trigger, then you can determine how many wheel revolutions would get you close to 500', and see if they are close.

 

[BBS360]

What you need to find out is how many pulses are required for the auto-cancel to trigger, then you can determine how many wheel revolutions would get you close to 500', and see if they are close.

That's a good idea. My work bench is pretty much setup for that test already. Might give it a try soon.

 

[BBS360]

That got put on hold. While putting together the breadboard to test the auto canceller I accidentally applied 12V straight to the 5V input on my arduino.
It fried.
Crimped test leads onto a 6-pin connector for the canceler unit. Not 100% sure what to do with the Yellow/Green wire. It's how the canceler cancels the signals but it must also have something to do with why the cancelers don't work with LEDs.

 

[esmith87]

That's a bummer I had a thought that maybe I could make a small pick-up unit down at the speedo drive unit on the front wheel. The shaft down there spins at the same RPM as the cable in the speedo, so if I turn up some sort of housing for a magnetic rotor and a reed switch that will screw into the speedo gear housing then I should be good to go, right? Or am I thinking about it all wrong. I am a machinist for a living, so design and manufacture are not an issue.

 

[BBS360]

That is probably the ideal solution. It could probably still be mounted at the speedo end of the cable so that you don't have to route additional wires down the forks.

I've wondered about making something similar to get tachometer readings while still using the stock tach cable.
I am not a machinist, so that idea got thrown out.