Help needed....

[PRider]

Hi all,

My bike is currently experiencing some serious difficulties at the moment. Last time I rode it was last summer and I stupidly rode it without air filters on the carbs because it was running very rich and i wanted to see how it ran getting a lot more air (I now know this was very very stupid...) So, at the end of that ride it barely ran and I just figured that I gunked up the carbs really bad... But being very busy at the time and not having the money to work on it either I let it sit until about 3 weeks ago. So I have pulled the carbs - cleaned them really well, re checked the floats and set them to 26.5mm - this is what I was running them at when it was running decent (because it was running so rich) and put them back on. When i tried to start it nothing happened - the starter was working but no ignition. So i pulled a plug cap and put another spark plug in there to see if I was getting good spark and there was no spark! - on any of the plugs!! - even with new plugs.
One time when i had the #3 plug out to check the spark something ignited cause there was a very loud explosion followed by a lot of black crud coming out of the plug hole and pipe. Could the problem be when I ran it without filters the crap got into the cylinders and really screwed something up? Or could sitting screw up the electrical this bad? everything lights up, just no spark... and I have never had any trouble with this before... I replaced all of the fuses, re spliced the coil wires and even got a brand new battery...

I bought a ohmmeter but I havent really figured out how to use it very well yet (electrical is definitly not my area). So any and all advice would be greatly appreciated. I know I probably fudged this one up pretty bad - live and learn i guess...

Thanks guys.

-Chad

[TopCatGr58]

Hey Prider,

Don't sweat the ride without air filters, unless you were running thru a sand storm!

Okay, you've got a 78E, the earliest and oldest of these fine machines out there! SO...when an 11 starts acting up, the first thing we suggest looking besides the carbs is THIS TECH TIP which will get you more introduced to electrical and wiring...your favorite thing!

BUT even before this, is the FUSE aspect! You said you replaced them. Are they the old glass ones in the old style clips?
IF so, then you get to test out the ohmeter, hopefully it's also a voltmeter/multimeter? First, pull the fuse for the Ignition circuit, then have the meter set to Ohms, and put one lead on each end of the fuse laying on something....not in your hands! Look at the meter, should be 0.00=no resistance, but a reading vs. ERROR/open or something else. This means the fuse has continuity...electricity can travel thru it=good! But if you don't get any reading...then fuse is bad, get another one, test to verify you have a good one! DO NOT PUT FUSE ON BIKE YET!

Next, set the meter to voltsDC, and clip or place the black(-) end against any exposed metal bolted to frame. First place red(+) on the positive pole of battery and check to make sure you get ~12 volts! Your ground(-) connection is good. Now turn ignition key to on, and then put RED(+) probe on one end of the ignition fuse CLIP, check for reading, then put on other end of clip, again check for reading. IF you get ~12volts on one of the set of clips, then you are getting power to the fuseblock/clips, and NOW you can put the KNOWN GOOD FUSE in. IF you don't get ~12volts from one of the clips, then you possibly have more problems?

Now with good fuse in, try to start bike or test for spark from plugs. IF no spark, then go to above PU coil tech tip.
Report back what you find, do, etc. IF it still won't get fire, and we'll think of something else!
T.C.

[PRider]

Hey T.C.

Ok, so, I tested all fuses - check.

Tested ground - check.

Tested first ignition fuse cap - check.

Second ignition fuse (the one touching my middle finger) - no good.

My fuse setup is a different than stock and i bought it like this when it ran AWESOME. (see photo). There is only one on the fuse block - a 20A. The other two are in holders - the white holder being a 30A and the black has a 15A in iit. Is the black holder the ignition fuse? (its the only fuse that would allow the lights to be turned on when removed) - and if so, would buying a new fuse holder like the one i have be the next move?

I didnt get to the coils yet, I thought i should report back my findings first.

Thanks.

PRider[IMG][/IMG]

[oseaghdha]

Looks like the white one is the main, 30A is correct.
The black one must be the ignition, but looks like they scabbed the headlights into it, which would be 10+10(?)

[TopCatGr58]

Hey Chad,

Wow, okay! So the fuse for the Black holder which "we" have deduced is the ignition one was good! I think Dan misinterpreted what you said about the headlights. You said the headlights/instrument lights would only work when the other fuses were in place, but the black one was NOT, correct!

Okay, one side of the fuse holder is the power side, and so you tested it and got 12 volts, right?! The other side is the downside, that goes to the rest of the ignition circuit, the TCI, COILS, etc., so it won't have any power coming from it, because it's coming from the first end you tested...flows thru the fuse and into the 2nd wire out to the ignition components!

So...as long as you're sure the fuse is good, and you've got power to the first end, then it should be good, and you can move on to the PU coils and such!

Then later, IF you want, you can order a replacement fuse block from me....see the tech tips! See, electrical isn't so hard!
T.C.

[oseaghdha]

Yeah, I didn't read carefully

But, it looks like there are three wires going into one end of the black fuse.
1. Red/White headlight (hot)
2. Red Ignition (hot)
3. Brown headlight

If the headlight is short wired, it would still work, even if the fuse is blown. I am guessing that the lights are fused only through the main(white holder) which would explain what Chad found. The remaining OEM fuse is the signals(20A).

Just a Wild A$$ Guess.

[TopCatGr58]

Hey Dan and Chad,

Okay, going by the wiring diagram and colors, looking at the wires closest to the taped harness....not the spliced in pieces.

The Brown/tan wires with the FUSE still in the OEM holder looks to be the turn signals. The SOLID RED wires are the MAIN fuse, not headlight. There should be 2 red/white wires, one is the lights, the other is the ignition. There should be 2 dark gold wires in the loom that are going to the black fuse holder, as well as the 2 red/white wires connected to the other end of the holder. I think the PO just was being cheap and spliced them together.

Chad, if you'll get a second fuse holder, and separate the 2 tan/gold wires from one end of the black holder, and the 2 red/white ones, and then run one fuse holder between each tan/gold wire and red/white wire, then you'll have it fused correctly, and the headlights won't be sharing the ignition fuse!

Let us know what you find, and what happens, etc.!
T.C.

[PRider]

Hey guys,

Man, the past couple days have been crazy busy and I havent gotten to the bike. Before I check the coil wires I have a quick question... - in the Tech Tips like that T.C. sent me it says to check the wires with the engine running - but since I cant do that should I just check the wires to see if one is loose? Or should I try to start it while jiggling some wires?

Thanks

[TopCatGr58]

Hey again,

Okay, first off, have you separated the 2 wires that are running thru that BLACK fuse holder and put an extra fuse holder in line, as suggested, so that you can isolate the ignition circuit from the light circuit??

Next, put a fuse in the holder, you've verified that you have power coming from the brown/tan wire on that holder. Then find the red/white wires to the ignition coils and using your voltmeter, turn the key on, put black test lead to ground/frame/bare metal, and the other red lead on connector for red/white wire to coil and make sure you have 12 volts on both coils.

You can test the PU coil wires with the engine off. At the TCI under the seat, you can unplug the connectors and test the resistance there. There is a wiring diagram in the tech tips, so you can figure out what colors are the wires to the PU coils, and measure the resistance, should be about 760 ohms IIRC??

You can also check the ignition coils, using ohmeter measuring from one plug end to the other on matched wires....1-4 and 2-3. With resistor caps, can get around 25Kohms. Take caps off and remeasure, should be around 15kohms. Make sure plug wire ends are clean/ free of corrosion, can clip off 1/4" or so with wire cutters IF green/corroded.

IF you can't get any readings on coils, measure the resistance of the caps alone also, and report on findings.
T.C.