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'84 CX650E that is evolving into a GL500
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Courtesy of Reg in Bristol. The 7805 is a 5V regulator and the green LED is specified because they have approx. 2V forward bias voltage so that if connected per the drawing the output will be close to 7V. If you can find a 7807 regulator you could connect its centre terminal directly to ground and accomplish the same thing.
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So i’ve read on here the gauges has to do with a faulty 7v regulator, does anyone here have a circuit diagram for it? from what I understand it’s easy to make
The 650E does not use a 7 volt regulator, I suspect that the turbo will be the same, no 7 volt regulator. Check the turbo wiring diagram to be sure.
 

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The turbo has a 7 volts regulator. Mine was also defect and I made myself a new one. Works perfect.
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'84 CX650E that is evolving into a GL500
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The CX650E does have a 7V regulator but instead of being in a separate housing it is inside the instrument panel. It is a bi-metallic strip type similar to the one examined in the link below except for the voltage. As he explains the reguulator's output is a series of pulses that average the required voltage instead of steady DC at that voltage but that works just fine with the heater type gauges these bikes came with.
 

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Does this regulator show in the 650E wiring diagram?
 

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I believe Murry (a member of this forum) has found a substitute regulator and stocks and sells them, Check with him.
 

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Discussion Starter #69
Thanx for all the feedback on the regulator, I think I might just have the right components here to build one🥳

Today I had another drive, and i’ve noticed the bikes has a slight misfire now and then, could it be dirty injectors? Speed sensor?
 

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Discussion Starter #70
Ok so started the bike up today after putting on the pipes, she purred beautifully until she got up to tempreture then all of a sudden it was a different bike, very slugish idle up until it dies when I don't keep my hand on the throttle, slight mis when revs are kept at 3000k.

I decided to take it for a ride a wow it's bad, no power, doesn't want to go into boost nothing, came back home, bike was only running on one cylinder, and the fuel system warning came on. For some reason my brand new plug on the right cylinder fouled, it wasn't wet or anything just blackened.

So I swopped it for a old plug, bike was back on 2 cylinders and fuel system light was off, drove now again to my fiances house and the bike just got worse the closer I got to her house, missing very bad with almost no power. And that is where I am now.

Could this be related to the pb sensor as I have seen on the forum there is a good chance mine is not within spec if it is still the original one? Its just so strange that the bike changed so suddenly when it got up to temperature, I could immediatly hear a change in the idle. I'm waiting for the bike to cool off now to verify whether it is temperature related and hoping it is just a small problem🤞
 

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Hi, from my knowledge and experience, pb sensor impacts operation at 3000 rpm and below. Mine would die when I came ro a stop, or run rough below and upto 3000 RPM. I swapped the pb sensor with a spare honda sensor I had and problem went away. In my situation, my bike ran well above 3000 RPM with bad sensor.
 

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Philip, since your problem is repeatable and the fuel sensor light came on the ecu should be displaying a fault code. Get the bike running and while exhibiting the issue, check the fault code lights on the side of the ecu, then compare to troubleshooting section in manual. Do not shut off bike or codes will clear. May want to remove seat and pull ecu where you can see it to get the codes. If a code is displayed, it should give you a hint of what the bike perceives is the problem
 
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Discussion Starter #75
Ok so I took out the injectors today, they are still clean and spraying nicely. Bought new plugs, this improved it but still its running like crap warm or cold. I’ve measured the coils and they seem to be fine. One thing I didn’t do is check fuel pressure because I don’t have something to measure it with. It has not displayed any fuel system error since that one time when it was running on 1 cylinder. I have no clue what it can be, took it for a drive and it has poor performance and not boosting as it should, it not smooth at all, it feels very hesitant and missing
 

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Discussion Starter #76 (Edited)
Ok I have found the problem. I decided to measure the speed sensor as per manual. The pickups themselves measured within tolerance. But as soon as I checked for shortage to ground I got a reading. So one of the wires shorted to ground. As I wiggled the wire the short would go away. I mounted it in a way where I got no short and took it for a test ride. Wow it worked😁, went nicely into boost and had strong pulls with no hesitation or misfire🥳.

So i’ll have to drop the motor to remove the speed sensor and fix it permanently. I used the original sensors that was previously fitted to the bike as I couldn’t track down the lx579 sensor locally. My guess is the wire is scuffed through on the tabs that is bent over on the wire on the mounting plate, but wont know for sure until I drop the motor again🤷‍♂️
 

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And here how to do it.

 

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And last but not least.... Changing the Pb-sensor

 
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