77 xs650 won't start after mods

2ManyHobbies

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First of all, I'm semi-new to motorcycle mechanics. I'm not a stupid person. I can usually figure both things out but I believe I have been My own worst enemy on this latest part of the project. I know there are a lot of people that don't agree with the mods that I'm doing and that's fine. I respect your opinion on keeping things classic but I'm a man who likes to Tinker with things and learn new stuff. Also, I have another one identical to this coming to me that will remain in the classic look. With that said, please be kind and give me any helpful advice that you may have. Thank you in advance

Here's the story
: 77 xs 650D. I first installed an xs charge pma kit. Bike ran great. Then I installed the Boyer bransden ignition (blue box). Had to learn about timing but I finally got it and it ran like a champ. THEN.... I got the idea to start redesigning the bike. I stripped anything electronic of to simplify, go batteryless using a Boyer 3 phase power box and even all that was working fine at first. I like three look of the striped down brat style or tracker. Anyway, it would still fire, run good and all electronics worked. Next thing I did after that was replace the carbs with mikuni vm34 round slides, and here's where I messed up maybe.. At the same time, I replaced the exhaust with short straight pipes. It fired a few times but was running irratic. The idle was up and down, I'd rev it and it would just stay up for a while unless I engaged the clutch. Then most of the time it would die. I spoke with the people at TC Brothers and they assured me that the carburetors were sent with jetting that would work for my bike even after telling them I had straight pipes and Boyer ignition. I set the fuel and air screw as recommended and even tried 150 combinations, remember I'm a little new to this. I was gonna to replace the spark plugs with new ones and they didn't have the ones the manual calls for but they gave me what they said was comparable. I did redo the timing (static) and was going to fine tune but it never would stay steady enough to do so. After a 3 week break I went back at it. I discovered I was not getting voltage from one of the 3 phase wires from the alternator. I believe this could have been a problem from the very start because when I rewired everything, I missed a ground wire grounding the frame to the motor and I remember at one point grabbing the key to turn the engine off when it revved super high and I got a pretty good shock. I traced it back and found the wires were brittle, corroded and one was broken completely. In hindsight, i probably got shocked because the wires that were breaking from the alternator probably were touching ground and putting voltage on the frame. So I bought a new pma kit and replaced the alternator. I now get voltage on all 3 legs but still won't start. I went through the fault finding guide for the Boyer ignition and everything seemed to check out except the magnets seem pretty weak. They didn't hold their own weight for sure but I do get a spark. It's a weak spark but I get one when rested against the motor casing. But when they're installed, I get no fire (gapped at .30). Every once in a while it goes once or twice but not enough to start it. Am I right by thinking it could be the spark plugs or weak magnets in the ignition stator plate? Or have I done too many mods at once and tuning this thing is way above my pay grade at this point? I'm not a stupid person. I can usually figure most things out, but I am stumped here and I may have gotten myself in over my head. I still want to learn and fix it myself. I know this was a lot and if there was something I didn't cover please ask. I would love to hear any thoughts.
 

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Is the Boyer Ignition really supposed to be ran without a battery? I think I read that they need decent voltage to work properly. Kick starting with PMA/ no battery may not give a sufficiently strong spark. The fact that you see a spark when holding the plug against ground while kicking, does not necessarily mean they will spark when subject to 140-150 psi compression pressure. For testing, I would recommend a chainsaw ignition tester, which basically is an enclosed spark gap much larger than the plug.
 
You can also hook up a temp battery to check the ignition and rule out voltage supply.

Were carbs synched? Can’t just stick em on and go.
 
You can also hook up a temp battery to check the ignition and rule out voltage supply.

Were carbs synched? Can’t just stick em on and go.
I actually have my old battery (in good shape) still in the electrical system while trying to get to the bottom of this. I also ran through the entire fault diagnosis that Boyer sent me. Weak magnets, or what it seems to me to be weak was the only thing on that list that didn't check out. Hell I was up and riding a little bit with all this on but it just stopped and I never could get it back again. I ordered some new plugs. NGK iraduim.. they were recommended in another thread to pair with high output ignition systems. It would be GREAT if that's all it is.

So I was told these carbs were stick on and go. He said they were plug and play, verbatim. There is some MUCH more in depth syncing instructions that I did not go that far but I know the slides touchdown and lift up the same time. I have the air and fuel set to what he told me and he also said the jetting would be just fine for my mods which I found hard to believe because I have ZERO back pressure. But like I said I'm just learning. I wish I would have done one component at a time like I was doing before. I got a little excited.

Thanks for your reply!
 
Welcome aboard!
Your story just reconfims my belief in the TCI system......sooo many stories.
I'll look into it but what is there TCI? What do you like about it better? And will it pair with a PMA and batteryless system? I know some don't. During my troubleshooting I do have a standard motorcycle battery hooked up but I've it's all good, I still have a small 12.5 volt battery in the system as you can see in the pic I posted before. Not big enough for a starter, just my digital gauge settings and to help the ignition.
 
I'll look into it but what is there TCI? What do you like about it better? And will it pair with a PMA and batteryless system? I know some don't. During my troubleshooting I do have a standard motorcycle battery hooked up but I've it's all good, I still have a small 12.5 volt battery in the system as you can see in the pic I posted before. Not big enough for a starter, just my digital gauge settings and to help the ignition.
TCI is the electronic ignition system Yamaha used on later 650's. Your '77 would originally have had points ignition, not TCI.
 
Not very helpful for the OP, but for a complete change of ignition and charging system, and the ability to run without a battery, a VAPE CDI/ PMA setup would be very hard to beat....
I just have very little confidence in a random PMA/ capacitor/ Boyer mishmash...(maybe even a mismatch.....)
 
Is the Boyer Ignition really supposed to be ran without a battery? I think I read that they need decent voltage to work properly. Kick starting with PMA/ no battery may not give a sufficiently strong spark. The fact that you see a spark when holding the plug against ground while kicking, does not necessarily mean they will spark when subject to 140-150 psi compression pressure. For testing, I would recommend a chainsaw ignition tester, which basically is an enclosed spark gap much larger than the plug.
Where I bought the electronic ignition at TC Brothers, it specifically says if you want to run batteryless with a Boyer digital electronic ignition and a xs charge PMA kit, then the Boyer power box is what you need, so that's what I bought. It did start with no battery at all and the power box. I'm really honing in on the fact that I think it's the magnet in the stator rotor for the ignition. They have almost no magnetic string at all. Get a very tiny spark, even with the new ngk iridium spark plugs outside the engine case much less inside. It would be really shitty to find out that they don't go together when they're marketing firmly says that they do. But I do have a 12 and 1/2 volt battery. It just is not suitable for starter
 
Not very helpful for the OP, but for a complete change of ignition and charging system, and the ability to run without a battery, a VAPE CDI/ PMA setup would be very hard to beat....
I just have very little confidence in a random PMA/ capacitor/ Boyer mishmash...(maybe even a mismatch.....)
Well it's not really mix-matched. The ignition and the the power box which is basically a rectifier regulator and capacitor all in one is made to work with the xs charge PMA kit but I wouldn't be opposed to switching the entire charging system and ignition system if I continue to have problems out of this
 
Not very helpful for the OP, but for a complete change of ignition and charging system, and the ability to run without a battery, a VAPE CDI/ PMA setup would be very hard to beat....
I just have very little confidence in a random PMA/ capacitor/ Boyer mishmash...(maybe even a mismatch.....)
 

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First of all, I'm semi-new to motorcycle mechanics. I'm not a stupid person. I can usually figure both things out but I believe I have been My own worst enemy on this latest part of the project. I know there are a lot of people that don't agree with the mods that I'm doing and that's fine. I respect your opinion on keeping things classic but I'm a man who likes to Tinker with things and learn new stuff. Also, I have another one identical to this coming to me that will remain in the classic look. With that said, please be kind and give me any helpful advice that you may have. Thank you in advance

Here's the story
: 77 xs 650D. I first installed an xs charge pma kit. Bike ran great. Then I installed the Boyer bransden ignition (blue box). Had to learn about timing but I finally got it and it ran like a champ. THEN.... I got the idea to start redesigning the bike. I stripped anything electronic of to simplify, go batteryless using a Boyer 3 phase power box and even all that was working fine at first. I like three look of the striped down brat style or tracker. Anyway, it would still fire, run good and all electronics worked. Next thing I did after that was replace the carbs with mikuni vm34 round slides, and here's where I messed up maybe.. At the same time, I replaced the exhaust with short straight pipes. It fired a few times but was running irratic. The idle was up and down, I'd rev it and it would just stay up for a while unless I engaged the clutch. Then most of the time it would die. I spoke with the people at TC Brothers and they assured me that the carburetors were sent with jetting that would work for my bike even after telling them I had straight pipes and Boyer ignition. I set the fuel and air screw as recommended and even tried 150 combinations, remember I'm a little new to this. I was gonna to replace the spark plugs with new ones and they didn't have the ones the manual calls for but they gave me what they said was comparable. I did redo the timing (static) and was going to fine tune but it never would stay steady enough to do so. After a 3 week break I went back at it. I discovered I was not getting voltage from one of the 3 phase wires from the alternator. I believe this could have been a problem from the very start because when I rewired everything, I missed a ground wire grounding the frame to the motor and I remember at one point grabbing the key to turn the engine off when it revved super high and I got a pretty good shock. I traced it back and found the wires were brittle, corroded and one was broken completely. In hindsight, i probably got shocked because the wires that were breaking from the alternator probably were touching ground and putting voltage on the frame. So I bought a new pma kit and replaced the alternator. I now get voltage on all 3 legs but still won't start. I went through the fault finding guide for the Boyer ignition and everything seemed to check out except the magnets seem pretty weak. They didn't hold their own weight for sure but I do get a spark. It's a weak spark but I get one when rested against the motor casing. But when they're installed, I get no fire (gapped at .30). Every once in a while it goes once or twice but not enough to start it. Am I right by thinking it could be the spark plugs or weak magnets in the ignition stator plate? Or have I done too many mods at once and tuning this thing is way above my pay grade at this point? I'm not a stupid person. I can usually figure most things out, but I am stumped here and I may have gotten myself in over my head. I still want to learn and fix it myself. I know this was a lot and if there was something I didn't cover please ask. I would love to hear any thoughts.
I converted to VM34's from TC brothers last October. I think they sent the wrong kit. The the pilot jet they had installed was the #12.5.The biggest one they sent me was 17.5. A main jet of 165 was installed. I called them the sent me a 20, 22.5, and a 25. It ran like shit with the stuff they originally gave me. I ended up with a 180 main 25 pilot, slide in the middle slot.
 
You mention some wires that were brittle and corroded. How old was that installation of the pma? Normally it would take many years for wires to corrode. The wiring on my bike is over40 years old and not that bad. It seems more likely that what you saw was evidence of too much current going through the wires, insulation burning off and wires stressed from too much heat. In a situation like this, where ever there was a small bit of resistance such as at connectors, there will be extra heat, wires will overheat and break off at the connector. I think you need to examine and replace everything connected to the overstressed circuit.
 
Everything is changed
It it was me I would replace the spark plugs to exactly the recommended ones .With the proper caps
Then I would work on getting a consistent spark Checking wiring and possibly use a battery
If I recall right the advance rod can be loosened and turned
Observing the spark --plugs out grounded the cylinder head Is important
Then when with the solid spark there both sides
I would set the ignition and perhaps move it a little listening to the sound shooting in exhaust to late
kickback to advanced
I feel there can be a need to adjust the carburetors but others here know more about that
 
You mention some wires that were brittle and corroded. How old was that installation of the pma? Normally it would take many years for wires to corrode. The wiring on my bike is over40 years old and not that bad. It seems more likely that what you saw was evidence of too much current going through the wires, insulation burning off and wires stressed from too much heat. In a situation like this, where ever there was a small bit of resistance such as at connectors, there will be extra heat, wires will overheat and break off at the connector. I think you need to examine and replace everything connected to the overstressed circuit.
I completely rewired it using a bigger gauge wire. It was definitely overheated wire
 
I converted to VM34's from TC brothers last October. I think they sent the wrong kit. The the pilot jet they had installed was the #12.5.The biggest one they sent me was 17.5. A main jet of 165 was installed. I called them the sent me a 20, 22.5, and a 25. It ran like shit with the stuff they originally gave me. I ended up with a 180 main 25 pilot, slide in the middle slot.
 
Mine came with 170s and 15 main and the third clip on the needle. . The extras they gave me are 12.5 and 17.5 165, 170 and 185. But I just realized I lost one of my sets so I'm going to have one of all the extras
 
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