Backfiring and uneven idle

[Easy Rider]

Originally Posted by roncg41677

I've thought about the side stand kill switch, but would that cause the engine to backfire?

I meant to bet a better video today, but didn't get to. I'll try for a sequel tomorrow. My friend called and is available early tomorrow morning to look at the carb, so I'll be doing that first.

Yes on the backfire.

I don't think you need another video clip. Your additional explanation makes it crystal clear.

I STRONGLY suggest that you should NOT mess with the carb because it is obvious now that the carb is NOT the problem. Check that side-stand switch. IIRC, it is fairly easy to by-pass it for a test.

[roncg41677]

Okay, went over to my friend's house this morning. He tore the carb completely apart. There was a bit of a clog in the idle jet, but nothing seemed horrible. It is idling a little too fast now, I think. I'll need to adjust the idle. At least it's clean now. I did notice the bike idles a little smoother after I put it back in, but...

...it's still doing it :pissed: . I looked at the kill switch, at least as good as I could sitting on the ground, putting the side stand up and trying to feel under the bike without it falling on me. It felt like it was making a good connection and pushing the button in as much as it should. It didn't push the button in completely, but about 4/5 or something. I searched quickly and couldn't find the test to bypass the switch Easy Rider. I'm getting ready to run out the door for a bit. I'll look again later.

Made another video anyway . Here it is:
[youtube:18aokbkz]http://www.youtube.com/watch?v=9mUCtUSEJkI[/youtube:18aokbkz]

for whatever reason, it doesn't do it as much the first time I put it in gear. The second time, however, when it was backfiring, I had the throttle almost pinned.

Also, for the record, you were right, Easy Rider. :whistle:

[music man]

Yea I think you have a safety switch problem, and also it might not actually be the "switch" not engaging or disengaging, but a short in the wires to it, so you can't really just push the button and say that it is not the problem.


Later

[Easy Rider]

Originally Posted by roncg41677

Also, for the record, you were right, Easy Rider. :whistle:

Just remember that NEXT time! :biggrin: :crackup

I am glad that the carb work did not introduce a NEW problem and make things worse. Sometimes it DOES!!

Experience is the best teacher. I just went through this same thing with somebody else a few months ago. He ended up having to get a new side-stand switch.

So.......here's the next step: Find the wires to the side-stand safety. Disconnect them. Be sure they are not touching anything, including each other. Start bike and click in gear. If the wiring and relays are good, I think it should die completely (side-stand down condition). Next, connect the 2 wires together with a clip or something else temporary. (Side-stand UP condition) Do the test again. If the bike keeps running.....that is, problem gone, the the safety switch needs cleaning and adjusting or replacement.

Just one possible problem with this: I may have the two conditions reversed; don't remember for sure. :??: The testing would be easier if you had a multi-meter.

This "test" is not documented anywhere so you can stop looking for it. If the problem goes away with the wires open or shorted, you could ride it like that .........but there is, of course, a danger in doing that.

[roncg41677]

Originally Posted by Easy Rider

The testing would be easier if you had a multi-meter.

I do have a multimeter. What would I check for with the multimeter?

[Easy Rider]

Originally Posted by roncg41677

I do have a multimeter. What would I check for with the multimeter?

The side-stand switch itself. With the wires off, in one position the switch should be wide open; in the other position, is should be a dead short. Note that in the position where it is supposed to be shorted, it may be intermittant due to engine vibrations. That might be hard to simulate with the meter; alligator clips for the test leads would help.

Edit later: I thought I remembered that there is something "funny" about the side-stand switch. It has a diode inside. It appears from the service manual that the switch should be OPEN when the button is out (side stand down) and closed (shorted via a diode) when the stand is UP.
I "think" you can still test it by removing the wires and shorting them together.......but now I'm not totally sure. It's worth a shot; certainly won't hurt anything.

[5th_bike]

With the multimeter on "diode test" it should give you a stable approx. 0.6 V readout for the side stand switch (assuming it's a regular silicon diode), in the position "side stand up". Test both ways (i.e. swap contacts), because only one way works. Once you have that, you know the switch itself is good, and it's in the wiring or the contacts.

Unfortunately the "continuity" test setting on the multimeter will give you "infinity" resitance for the switch, even when the switch is good... because of the diode.

But you CAN test the individual pieces of wiring going to and from the side stand switch, of course, with the "continuity" test and with the 'ohms' (resistance) test.

I have not followed the discussion for a couple days as it seemed a carb thing, but I agree with Easy now, it looks like a contact or wire issue for the side stand switch. There should be a little current going through the wiring via the side stand switch, and in this case there is just not enough being able to go through. It is not a 'short' thing, but a 'bad contact' thing. Try loosening all contacts for the side stand wiring, and tightening them again, then try your bike.

[5th_bike]

Yours has "diode test" and "continuity' in one setting, with black border and black diode symbol, on your dial at about 175° - almost 'south', between "200 ?" and "wave with red border".

You test the two wire ends that go to the side stand switch. One (I know off the top of my head) is at the side stand relay, try connecting the red probe of your multimeter there first. I don't know where the ground connection for the side stand switch connects, after you find it, try there, first with the black probe tip.

With the side stand up, it should give you about 0.6V readout - NOTE only in one (!) of the possible two ways to hook it up. If you do not get a readout in either hookup, or you get a readout that is unstable when you jiggle the wiring, you know that there is a bad contact somewhere... in between the side stand relay, and where the side stand switch wire grounds.

If you can unhook the two wires from the side stand switch itself, you could test each individual wire, the "continuity" should give a beep (mine does) and/or the multimeter readout should be close to zero ohms.

Hope this helps. Sorry to say I have not (yet) disassembled my sidestand relay wiring...

Edit: I could have sworn you posted a reply with a picture of your multimeter in it... it probably was a dream... a mental message... or :bong: ....

[roncg41677]

Originally Posted by 5th_bike

Edit: I could have sworn you posted a reply with a picture of your multimeter in it... it probably was a dream... a mental message... or :bong: ....

There was. I deleted it because I did what I should have done in the first place, check the meter manual :roll: .

When I put the side stand up and checked the green connector the meter read 608. I'm assuming that's .6v. I had had the side stand down the first time :blush: . I can't even see the connection at the switch itself. It's mounted on top of part of the frame inside of a little housing. Any suggestions on how to get to the wires at the switch?

I removed the relay, although checking it per the service manuals instructions is a little confusing.

TURN SIGNAL/SIDE-STAND RELAY
The turn signal relay is corporated with the side-stand relay and diode to form the one component part which is called the turn signal/side-stand relay. It is located under the luggage box.
• Remove the front seat. (See p. 5-1.)
• Remove the luggage box

SIDE-STAND RELAY INSPECTION
First check the insulation between "D" and "E" terminals with tester. Then apply 12 volts to "D" and "C" terminals, "+" to "D" and "-" to "C", and check the continuity between "D" and "E". If there is no continuity, replace turn signal/side-stand relay with a new one.

What is checking the "insulation" and how do I "apply 12 volts"?

[5th_bike]

Hold on, at this point there is no reason to inspect the side stand relay as in the manual, even though there is an ever so slight chance that the error is in there. You could test that by checking for a stable 0.6V between the orange wire to the side stand relay and ground; with the side stand down, the bike in neutral, and the side stand switch connector loose.

:oops: Oh, I forgot: when you do the testing as in my previous post, make sure the bike is in gear, otherwise the good connection via the neutral switch could mess things up. Sorry again.

Looking at the wiring diagram on page 205 of the user manual, for now I would concentrate on the two (orange and black/white) wires that go to and from the side stand switch. If you already loosened the connector on the way to the side stand, and you checked a stable .6V with the multimeter diode test for the side stand switch itself, the side stand switch and the contacts there are good, no reason to take it out.

Then, it is either the orange wire from the relay to the connector, or the black/white from the connector to ground. Check the wires with the "continuity" setting; or measure their resistance, which should be close to zero ohms. Also wiggle the wires a bit (have your son help, while you hold both ends of the multimeter) to simulate the vibration of the engine, and see if the readout changes.

Lastly, closely inspect all copper surfaces of the connectors, if you see a funky spot on one of the connectors, like a discoloration, try to clean it so it makes good contact.

On the side, "apply 12V" means: connect a wire to +12V (I suggest the orange/blue wire at the right side of the horn - it has a fuse, but needs the key 'on' to be active with 12V) and D, and connect a wire to 0V (the black wire at the battery) and C, then there should be continuity between D and E (i.e. the relay is activated). However, your bike works fine in neutral so I wouldn't worry about testing the relay as described here, now.

Edit (add): 1) "insulation" means, there should be no contact between D and E when the relay is not activated. Resistance = infinite.
2) All tests, please do with the engine off.