I thought I was an ok mechanic untill.....

I cant get the damn thing to spark. Picks show bounce on the volt meter when the engine cranks over, coils ohm out fine and i have a couple new used tci boxes. WHAT NOW?!?!?!?!?! I'm about ready to sell the damn thing as I've put about a grand into buying and trying to get the thing running and I haven't had so much as a backfire out of it. What now. I already replaced the fuse box and checked my conections a couple dozen times. The coils have tweleve volts running to them I just don't have so much as a hint of spark. I'm beyond desperate and ready to put it on craigslist. Please help me out here

 

Tiny, you forgot to tell us what bike you're talking about, and I did not see you list 12 volts at the coil plugs. Give us more info.
Bill

 

Sorry bill. It's a 1980 xj 650 maxim.

 

side stand relay. Disconnect it and see if you have spark. It is a light green/lime green connection in the headlight bucket. Make sure that the side stand switch is functioning correctly. I'm betting it is the relay. My buddy had the EXACT same problem on an 81 xj 650

 

Tiny, put a hold on the craigslist thing. The gurus here are WELL compitent enough to diagnose your issues. Just hang in there and see what they say. I have this exact bike...year and all and it runs like a top.

 

mc I don't think the 80 model has the relay on it. I could be wrong, but my bike doesn't have it and it's an 80 model

 

Second that Side Stand relay. Got me twice bashing my head against a wall. "WHY WONT IT WORK" Is all I could say for an hour.
Sat on it, kicked the stand up, pressed start.
And nearly passed out with relief

 

Not to distract from Tiny's issue, but I am now confused. Does the 1980 models HAVE the kickstand relay on them? I can start mine sitting on the kickstand. I was under the impression that the 1980 models did not have the relay installed on them yet. Can someone clarify this for me?

 

No, the 80-81 650 Maxims do not have a sidestand relay.
They do have a clutch switch...

 

Thanks Robert. I was beginning to think that I had yet another relay that was not working!

 

You can start a bike with the sidestand relay IF it is in neutral with the stand down. It won't crank in gear with the sidestand down....

The 80 is simpiler and cuts off the starter unless in neutral or in gear with clutch in. Later models have starter and TCI cutoff.

But not the issue here - Spins, 12V to coils, TCI appears to functioning, pickups appear good. Coils test good with ohm meter. No spark.

Let me some basic questions, just bear with me. When stumped I like to go back to ground zero.

How are you determining you have no spark other than no start?
Have you check the coils ground all the way back to the battery?

When you check a coil you should remove the plug caps. Assuming you did that are you sure your plug caps are any good?

How about the connection to the wire for the caps? Very common for this to corrode. You can snip a bit off the wire for a better connection - just watch your length.

 

I'm with Bill, back to basics and build a foundation of knowledge to further the effort.

 

Bill, I have no spark to the plug. I pulled the wire and stuck my finger in it to make sure. Plug caps are good. I have not traced my ground back to the battery. I'll do that this evening. No corrosion in the caps. sgknies, I have no doubt they can figure out what the issue is, its just a matter of how much more time and money it will take to get it running. Im beyond frustrated and I refuse to spend another pennie on this thing until I see spark.

 

I can understand your frustration I tuned my bike Saturday and just now had to clean 2 plugs (again) to get her running on all 4.It's a labor of love. Most of us have reached that point. Best thing to do is take a bit of a break.

Once you are ready let me clarify. When you say ""I pulled the wire and stuck my finger in it to make sure." you mean with the plug cap on or off?

Have you examined the wire where the plug screws into?

I see you have a parts bike have you tried the other coils?

Sorry if you have been through all this before just trying to see what the heck is going on. Has to be a logical reason.

 

I pulled the cap off the plug and stuck my finger where it conects to the spark plug to see if I felt a shock. nothing. I tried the coils off my parts bike and still no luck. I don't think I can possibly have four bad coils.

 

I don't think I could tolerate the feeling of ZAP on purpose, haha. I had to replace my actual plug boots - coils were fine, but the stock boots (caps) were crapping out.

You could also try cutting a wee bit off of the spark plug wire and screwing the cap back in further down the line to hope for a better connection.

 

Finger in the plug wire - not a good trick to see if you have spark. Hot damn man. I thought it was bad of me to grab a plug wire and rip it off while running ... O_O

Keep a plug in it, and ground it to the head.

 

I had to do something and I wasn't sure the plug were any good. Chalk it up to being up at four in the morning frustrated at a bike that should run but doesn't.

 

Even though there's no sidestand relay, does this bike have a "safety" relay? If so, locate and unplug it. The safety system works by dropping the TCI to ground so it can't produce a spark...

 

Where would this relay be? Whats it look like? Sounds like a definate possibility. And I think we can all agree my method of testing for spark was a dumb ass move. But you have to admit I now know for sure that there is nothing getting threw to the plug. I can imagine what would happen if it had sparked and wont be testing with this method again. I went out and spent ten bucks on a spark tester a couple days later.

 

On the 550 it's under the main frame tube under the gas tank; it has a gold anodized case and a 4-wire connector plugged into it and it's in a rubber mount.

I can't tell you exactly WHERE it is on the early 650's, another 650 owner will have to narrow it down for you.

 

If the engine cranks then all the safety circuits are working. That boils it down to the ignitor unit, the pickups, the coils, and of course the wiring.

Check the following:

Ignition coil primaries: (measure at the Ignitor plug)
2.5 ohms +- 10% (between Gray and Red/White wires)
2.5 ohms +- 10% (between Orange and Red/White wires)

Pickup coils: (measure at the Ignitor plug)
700 ohms +- 20% (between Gray and Brown wires)
700 ohms +- 20% (between Orange and Black wires)

Ignition coil secondaries: 11k ohms +- 20% (measure between spark plug wires on same coil)

Make sure Black wire measures 0 ohms to the frame and that there is +12v on the Red/White wire at the Ignitor plug with the switch on. Check to see that there is no corrosion on the connectors.

If all the above is correct, look at is whether or not the Ignitor plugs are making a good connections to the Ignitor unit. Sometimes a female connector loses tension and does not grip the male connector properly (please - no jokes) causing an open circuit even though everything looks fine. You can check that by plugging in a male connector of the same size as the ones on the Ignitor unit and testing the grip and continuity of each female. Or you can take out the females from the plug with a special tool an test them that way.

My guess that there is some kind of wiring problem since I doubt you would have multiple bad coils and Ignitor units.

 

Labor of love..Got that right Bill...I am so full of love I can't stand it lol. All kidding aside bill, Does his bike have a diode block. Putting the block in my bike made it all work, of course I did not have one where it was suppose to be ( But thats another story ) TINY TINY TINY It is obvious you have never been zapped from a plug wire or you would have never tried that approach, I have, and it knocked me on my butt and scared the h*ll out of me. Never again.

 

I just posted the same issue with my 1982 XJ550. All these replys are also helping me...thanks.

 

For what it's worth, I went through the same trouble when I brought my maxim home..... in buckets on a trailer. Halfway through reassembly I was bald.... But when the dreaded no-spark condition popped up, I bought a wig (laugh now, please lol) and went back to basics. An electrical schematic is a lifesaver sometimes, and it was used to check almost EVERY wire on the bike.... time consuming? YES. Tedious? YES. Worth it? YES! Now my $200 750 Maxim is running fine... for now ;-) Hang in there and talk to these guys.....

 

just curious but is your battery 100% charged? that was my killer, everything checked out good for having about 12 volts. it wasn't until several days later when i charged the battery that the full 12.6 volts showed my pickup coils as bad. the sad part is as a mechanic i should've known better. i'm with Bill, walk away for a bit. you've no clue how many times i did that and walk back and go "duh"

 

I am walking away for a couple days and working on the xs or the dt1. When I can stand to look at the thing I'll go through the tests gitbox suggest. Does anyone have a electrical diagram for the damned thing?

 

A break will help - based on your first post I assumed you did the tests Gitbox suggested. If you have not you really need to. Good luck and let us know. We will get to a solution.

 

Like they say Tiny, A picture is worth a thousand words, I bought a Haynes manual on ebay for 20 bucks for my 750. Best 20 bucks I spent on the bike. Combine that with the help on this forum you will get it running. And yes walk away sometimes is the best thing to do.

 

I got hooked up with a manual and noticed a clutch switch. Does this mean I need to be pulling in the clutch in addition to having the bike in neutral?

 

No. One or the other.

 

Tiny, if you look at the schematic you will see that the safety switches only prevent cranking the engine. There is no normal situation where the engine cranks but the ignition is disabled. If you can press the starter button and the engine spins then they all are working. (or bypassed)

The only thing that kills the ignition is the Kill switch which removes power from both the igniton and the starter circuits.

One thing I forgot to mention is to see how low the +12v goes when measured at the Ignitor unit (Red/White wire) while the engine is cranking. If it drops too low there won't be enough for the ignition circuit to work.

 

Thanks, I see that on the schematic now. I will meassure the 12v and let you know.

 

The voltage started at 12.8v and droped to 12.2v while cranking. And I don't have a r/w wire. It was red and tan.

 

Red/Tan sounds like Red/White but dirty/aged.

Anyway, when you measured the voltage, and for that matter, when you measured the resistances of the coils and the pickups, did you do it at the TCI connectors? Measuring at the TCI connectors will validate whether you have a wiring problem at the same time as validating the components.

Second question, have you verified that you have no spark from either pair of plugs (1/4 and 2/3)? By the way, especially since this is a wasted spark system, I would recommend you check for spark by putting a plug in the boot and resting it against the block or head so that it has a good path to complete the HV circuit.

Third, have you verified resistance from boot to boot on each of the coils? Should be about 21K Ohms from boot to boot (e.g. from the boot of plug 1 to the boot of plug 4).

I assume from the two threads you have going that you also have some other, theoretically good, TCI units to try. It's certainly sounding like you have a bad TCI, or the wrong one for your bike. Some models have a TCI disabler that's engaged by the side stand relay. If you've got a disableable model on your non-side-stand-relay bike, that might be the problem right there.

 

I do have some good tci units to try. I meant to end the other thread. I measured the voltage at the tci. The resistence is gonna have to wait because either there is no resistence on anything or my meter has said farewell (it is older than me). So when I get paid thursday I'll go get a new meter. I beleive I have the proper tci now but if someone wants to give me the proper numbers to check I would appreciate it. I've been reading the manual most of the day so hopefully something there will give me my answer. Also does anyone know how to test the oil level sensor? Also if you read the whole thread you will notice I have already checked for spark in a effective yet unapproved way.

 

According to Motogrid, the correct TCI for a 1980 Maxim 650 is 4H7-82305-10-00.

 

Your TCI will be labeled as follows:

OEM TCI Ignitor Unit
small black label marked:
TID14-02
4H7-10 (stamped date code)

 

Thanks guys. I do have a correct tci. two actually

 

Tiny,

There is a meter on the dash of my pickup parked at the house. The window is open so just go and pick it up. If anyone gives you any grief just tell them I sent you. You can keep the meter for future use and I'll pick up another one.

If you want to call before you come out use my number but add one to the end. My wifes number ends in 4126.

Loren

 

Thanks Loren. But I got my meter fixed. I have this thing about tinkering so I had to open it up to see what happened. Blown fuse. Simple enough. The coils ohmed out great. Getting ready to go test the pickups.

 

The pickups ohm out ok as well as the black to the frame. What now guys?

 

Well, we're kind of back to the original questions:

1) How did you verify that you have no spark on either channel? (and don't do the "finger in the socket" thing)

2) Is one of the "known good" and correct model TCI units on the bike now?

The one other, new, question I would ask is whether you've actually removed the timing cover and verified that things in there look correct... should look more or less like this:

 

I hooked up a plug and grounded it on the head with nothing. Also The spark tester I got from schucks shows nothing but its a cheap tester so I don't really trust it. I pulled the timing cover and it looks pretty much the same. Could the pick ups be bad and still ohm out ok?

 

Tiny, Have you checked the correct operation of the kill switch on the handlebar? I know the bike will crank with the switch in the off position but it sure won't start. My '81 was intermittent until I took the switch off and cleaned the bugs and spidey webs out of it. You should be able to bypass the switch with a piece of wire and a couple bullet connectors.

I have the factory manual from Chacal but I don't remember what years it covers. If you wantto borrow it tomorrow leave me a text message on my phone and I can leave it behind my house on the gas meter for you. I don't get off work at the hospital until 0700 hrs and then I'm going to close on new house at 0800 so I won't be able to leave the manual out until 0900 or so but you're welcome to use it.

Loren

 

Tiny, you're still not answering questions in their entirety. Did you check plugs from both the 1/4 and 2/3 ignition channels, or just one plug?

Did you Ohm out from cap to cap on the two coils?

It's pretty unlikely that the pickups would Ohm out OK if they were bad. I wouldn't say it's impossible, but it's pretty close.

 

I tested all plugs. Ohmed out the the coils from cap to cap. I've read that the pickups are magnetic. Is it possible that something with the magnets is bad?

 

I'm leaning toward something to do with the pickups. How does this magnetic pickup system work?

 

The pickups are coils wrapped around magneric cores. When the reluctor moves past the pickup it disrupts the magnetic field, first increasing flux, then reducing it; this change in the flux density induces current flow in the winding, thus generating a voltage signal.

I think at this point you need to get someone involved who has an oscilloscope and familiarity with this type of an ignition system. Either you have the worst luck in the world with "known good" TCI units, or we've not been communicating accurately as to tests to do and results found.

One question I should have asked earlier is, "what is the history of this bike?" Have you ever had it running? If you got it this way, then I suppose the most likely explanation is that your wiring is non-standard, thanks to a PO, and you should be tracing everything in the igntion circuit relative to the wiring diagram to see where things have been customized to a non-viable state.

 

Other then the spray paint over the wiring harness the PO did not do anything to the wiring harness. I cant believe that my luck with tci units is quite that bad. What is an oscilloscope? And could there be something wrong with the reluctor or is it basically a hunk of metal that swings by the pickups? I'm not willing to give up and turn this over to someone else yet. I've come to far and I'm learning to much to stop this short of an answer.