front brake cruise control switch??

[garyS-NJ]

I have an '84 venture royal xvz12D with cruise control and I wanted to split the brakes by running two lines from the front master cylinder to the front calipers (and of course rearrange the rear brake lines..). Knowing that the 1984 front master cylinder only has a 12mm bore which might only be good enough for the one two piston caliper, I picked up a 1987 venture front master cylinder. so I just cut the wires for the front brake switch and see my original switch has four wires (brown, Yellow, black/white, and green/yellow).but my 1987 front master cylinder only has three wires (brown, Yellow, black/white). I took a look at the schematic and see that the power comes into the switch on the brown and when the brakes are depressed, that power is switched out to the yellow wire to light the brake lights. Same for the rear brake switch. I THINK THE GREEN/YELLOW WIRE IS FOR CRUISE CONTROL//

 

schematic has the power coming into the rear brak switch on the brown wire and when the rear brakes are not depressed, that power comes out of the rear brake switch on the green/yellow wire and into the front brake switch./ and when the front brakes are not depressed, that green/yellow wire with power is switched to the black/white wire. from there, the power is routed on the black/white wire into the clutch switch and out of the cluth switch normally closed position to the cruise control unit and cruise control solenoid. I can only conclude that grabbing the front or rear brake or grabbing the clutch interrupts power on the black/white wire to the cruise control and turns off cruise control./ so my idea to use this front master cylinder is to connect the green/yellow wire to the black/white wire. All this should do I think is it will not allow me to turn off cruise control by depressing the front brake. Yes, not safe as possible but I want to get riding now with this master cylinder and "someday" I'll look for a four wire front master cylinder (someone said 1990's virago master cylinder will work).

 

comments??

[Great White]

It's been a while since I looked, but I'm pretty sure you can just swap your 84 brake switch on to your 87 master cylinder. Or I might be thinking the 85 switch and the 86+ compatibility.

 

Check it out and see if you can just transfer it over. I'd walk out to the garage and check (I've got an 83, 85 and an 86 master cylinder out there) but I can't really walk right now so I can't go check.

 

But if you can swap them, problem solved.

 

If you can't, I'd just leave the cruise control inactive. Of all the things you definitely want to cancel the cruise, it's absolutely brake activation.

 

I'd have to dig through the wiring diagrams to say if your scheme even has a chance of working. I would say if Yamaha could have made it that way they would of (IE: less wiring, less cost). By rigging something up, you could be risking blowing a controller in the cruise circuit.

 

Again, I'd have to get down into the wiring diagram to say yes or no either way....

Edited October 14, 2015 by Great White

[garyS-NJ]

wow, I looked at the switch and it wasn't obvious how to change and immediately started thinking how I could use the 87 switch with the '87 master cylinder... yes, either brake or clutch must be the trigger so my solution should just take the front brake out as a trigger. your solution keeps the front brake in the control..

 

THANKS!!!

[Great White]

wow, I looked at the switch and it wasn't obvious how to change and immediately started thinking how I could use the 87 switch with the '87 master cylinder... yes, either brake or clutch must be the trigger so my solution should just take the front brake out as a trigger. your solution keeps the front brake in the control..

 

THANKS!!!

 

Hmmm, I'm not picturing how you would keep the front master in the circuit if it doesn't have the 4 wire switch.

 

But here's a solution that should work: use the brake light trigger to also trigger a 12v relay (pins 85 and 86). Then take pins 30 and 87 to trigger the brake signal to the cruise circuit.

 

http://autoacrepairs.com/RelayWiringGuide.jpg

 

Now your brake light will control the cancel for the cruise by activating the relay with the brake light. A little bit more cumbersome than just using the integrated front master switch, but much safer than not having a cancel signal from the front brake master cylinder.

 

There is a small added bonus that you can buy those relays anywhere should you be away on a trip and one craps out on you.

 

Incidentally, that relay scheme is how I'm going to wire up venture cruise in my 89 FJ1200. That way I can continue to use the OEM brake switches (front brakes, rear brakes and clutch) and still trigger the cancel in the cruise circuit. Of course, the entire wiring harness in the cruise circuit is going to be custom built too since the FJ1200 never was offered with Venture cruise. Good thing the 85 system I'm using can be made to work as a stand alone system.

 

 

Man, I wish I wasn't stuck in this bed right now but I just can't risk the steps. I'm sure the 4 wire switch will just swap over.....if only I could get to the garage to look at those parts......

Edited October 14, 2015 by Great White

[garyS-NJ]

Yes, I think swapping a switch better than burying another relay.

[garyS-NJ]

I think connecting the green/ white in to the black/white out just bypasses the front master cylinder switch so it can no longer open the circuit to cancel the cruise control

[Great White]

Your call bro.

 

Personally, I'd leave the cruise inactive until I could figure out a way for the front brake to cancel the cruise.....

[syscrusher]

This is confusing to me without looking at the diagrams. I would think that the newer model would have four wires because the front brake switch triggers the electric anti-dive solenoids.

Unless that is sensed in the CMU/Monitor circuitry it would seem that an additional circuit would be needed for the additional functionality.

[Great White]

This is confusing to me without looking at the diagrams. I would think that the newer model would have four wires because the front brake switch triggers the electric anti-dive solenoids.

Unless that is sensed in the CMU/Monitor circuitry it would seem that an additional circuit would be needed for the additional functionality.

 

I'm thinking the 87 master he has is probably a standard model without cruise.

 

The 86 model wiring harness I have to put on my 83 has the "break outs" for the anti dive solenoids further down the harness.

 

Edit: just had a quick look at a 90-93 diagram and it seems the EAND relay is triggered off the brake switches. But it was a quick look and its a little hard to follow on a 7" tablet....

Edited October 14, 2015 by Great White

[Great White]

Ok. So after a 40 min walk out to the garage (it's 25 feet away by the way!) I've had a look at a couple master cylinders.

 

The switches are interchangeable in the housing from what I can see. At least my 83 and 87 housings are. My 83 doesn't have cruise, the 87 does/did.

 

Pop the little plastic cover off the lever pivot bolt on your 84. Just stretch it open enough that it will slide off the bolt.

 

On the underside is a hole. Up in that hole is one way plastic clip that holds the switch in. Pull a little bit of pull pressure on the switch and very lightly depress the plastic tab with something that fits in the hole. It's fragile (old plastic), so be gentle.

 

Once the tab is depressed enough, the switch will slide right out of the brake housing.

 

Do the same with the 87 master cylinder housing.

 

Once the 87 switch is out, just slide the 84 cruise brake switch in until you hear/feel a "click".

 

Presto, you're done.

 

Now you can just plug the cruise brake switch right into your bikes wiring harness as OEM.

 

No muss, no fuss.

 

[garyS-NJ]

well close. I cut the electrical wires on the 87 to pull it off the scrap bike and couldn't reach the connector on my bike without taking things apart (think it's buried under the headlight). Thanks greatwhite for the tip on that plastic cover. I looked at it for 3 seconds and decided I would have to check the manual.. then when I saw 3 wires vs 4 wires I was just looking for a way to wire it in. I think it's called bias when we think on way (often stupid) based on a particular mindset.

[garyS-NJ]

somebody shoot me. I was looking at the schematic again to see what I was thinking and said to myself "three wire"??? makes no sense. So I went back outside with my glasses on and saw the fourth wire buried in the jacket.