84 Heritage Starter Lockout Relay Logic

[canuck1969]

Working through an issue with the Starter Lockout Relay Logic. I know my relay has a bad diode in it. Bike will start in neutral and can ride it through all the gears but when the bike is in gear and the clutch is in it will not trigger the relay and send power to the starter solenoid. Not an issue with the side stand and I have rang out all the wires and switches and they seem to be doing what they are supposed. I know the issue is the relay but the drawing below shows a second diode in line somewhere. Anyone know where this diode is located? When I run a continuity test on the Sb (Sky blue) wire from the relay and get different readings in resistance if I switch the probes around between the wire and ground. I have not run a diode test on the wire yet but does this diode even exist in line (other than the one in the relay). My readings seem to indicate that it does but frankly not sure where it would be. I want to rule out this as another possible issue with the control. I want to retain the clutch, sidestand and neutral switches operational...I am funny that way.

I tried to source a new relay but not worth the $100+ CDN for an OEM and the aftermarket one I ordered on Amazon for $15 was not the right one even though they said it was. No diode in it.

Thanks

 

[5twins]

I'm not familiar with an in-line diode but if there is one, it's probably buried up in the harness somewhere under the tape wrap. It's probably more trouble than it's worth to try and find it. But, it probably isn't the issue. The sidestand switch works through that same diode and it's still working, right? Also, the diode shown in the clutch relay looks to be on the neutral wire line, and you say the relay works when the bike is in neutral. That would leave the clutch switch as the culprit. It should connect to ground when activated, going through the closed sidestand switch. Let me ask you this - will the starter engage with bike in gear, clutch pulled, sidestand up? Maybe what you've encountered is normal, but a minor short coming of the design.

 

[canuck1969]

I agree. I don't think this second diode even exists and if it does not worth the trouble to find it. Clutch switch is working fine. When the lever is out (switch is engaged...had to double check that and yes, when the clutch lever is out the pin is in and the switch is open) there is no continuity to ground. Pull the lever in and you have ground on the black yellow wire. Everything rings out properly. Bike does not engage when in gear and side stand up. The signal goes to ground on the relay but does not transfer the power to the second red/white wire when the lever is pulled. I bench tested the relay and the diode in the relay is toast which is why it does not work. If I short the Sb and B/Y wire on the relay then it will start in gear with the side stand up. Makes sense as it now used the power on the neutral side of the relay that is working to flip the coil. Only thing is the neutral light turns on when I pull the clutch in because now the neutral light is grounded May be lesser of two evils.

Just want to see if this second diode even exists but I agree that it is mostly likely irrelavant right now and working. I can add a second relay for just the clutch switch if I had to. The relay they use is a special single pole/single throw relay with a diode. The main input power is shared between the coil and common and the coil can be fed with two separate signal grounds because the diode keeps them apart Not easy to find and very expensive. Interesting design used to reduce the wiring and eliminate a second relay.

 

[5twins]

All this added complication and chances for problems to occur are the main reasons I eliminated all that safety B.S. on mine. It's easy to do without cutting any wires or changing any around, so the stuff could be added right back in if you wanted, but I don't see why you would. The clutch relay requires you jumper the 2 R/W wires together to restore the power path to the solenoid, that's all ......

The starter will now work any time, clutch pulled or not, bike in gear or not. I see the safety aspect of not allowing the starter to operate if the bike is in gear without the clutch pulled, but older bikes never had this and the world didn't come to an end because of it, lol.

 

[canuck1969]

All this added complication and chances for problems to occur are the main reasons I eliminated all that safety B.S. on mine. It's easy to do without cutting any wires or changing any around, so the stuff could be added right back in if you wanted, but I don't see why you would. The clutch relay requires you jumper the 2 R/W wires together to restore the power path to the solenoid, that's all ......

The starter will now work any time, clutch pulled or not, bike in gear or not. I see the safety aspect of not allowing the starter to operate if the bike is in gear without the clutch pulled, but older bikes never had this and the world didn't come to an end because of it, lol.

I know. I may come to this conclusion but my other two bikes have them and sometimes muscle memory is a bitch when switching bikes. I may work something out. I have this nasty obsesion to making things work the way they were designed. Its a curse........

 

[5twins]

Around here, we generally try to improve these old 650s. Granted, the later models saw some changes and more refinements, but I don't feel everything they did was an improvement. Some of the stuff was government mandated, like the emissions stuff and possibly the always-on headlight. Some of the stuff was just cost cutting, like eliminating the grease fitting on the rear brake pedal pivot. I plan to remedy all that stuff eventually on my '83. I will install an older right side handlebar switch assembly with the headlight on-off switch and also eliminate the headlight auto-on feature. Later models wired the tail light into the ignition switch so it comes on with it. I'll be changing that too. The sidestand switch and relay, along with the clutch switch and relay, are already gone, along with the RLU.

 

[canuck1969]

Done.

Secondary relay to compensate for the failed starter lockout relay. Just used the 4 pin one I got that was not the right one for the startup. Operates the clutch and side stand interlock side of the safety when it is in gear. Everything back to original operation now. I know some guys don’t like the interlocks but is what it is.