Help! Bike cranks fine but won't start.

[DSmithjr]

Well, I went through the testing procedure on the ignitor and I'm not sure what to make of the results. Of the 56 possible terminal testing combinations (as seen in the chart on page 6-21 of the manual) only 4 were in the proper listed range. The two that are suppose to be 0 were zero, and the negative (-) on 5 and positive (+) on 3 produced a result of 0.4 as did (-) 5 and (+) 4. Those are the only 4 terminal combinations that were correct. Another 10 of the testing combinations produced results that were all above the listed range. What has me somewhat confused is that most of the combinations didn't produce a measurable result. I wish I had a ignitor I knew was working that I could test just to see if all of the different terminal combinations produced a result.

One way or the other, the results of this testing have me now thinking my ignitor is indeed bad. If someone thinks my interpretation of the results is wrong, please say so. If anyone has had one of these tested before, I would think you'd know more about it then I do. I'm just going strictly by the results I got from my tests. I think I'm going to purchase an ignitor off eBay. I want to thank adrianinflorida for posting the email like with the $55 ignitor.

I'll carry on with some other tests from chapter 6 while I wait for the ignitor to arrive.

[Easy Rider]

Originally Posted by DSmithjr

Well, I went through the testing procedure on the ignitor and I'm not sure what to make of the results.

Yes, after looking at the manual page, I can easily understand that.
To put it nicely, something was lost "in translation".

"Measure the voltage between the terminals in the following table.
09900-25008: Multi circuit tester set Tester knob indication: Diode test"

So, with the ignitor removed from the bike for testing, there will not be ANY "voltage" present anywhere. Unless you have the exact meter that they specify.....or a reasonable copy.....AND have it set to "diode test" with the ignitor removed.........all your readings will be totally meaningless.

If you have a digital multi-meter with a "diode test" selection available, you might want to give it another go.....with the ignitor unplugged, that is.

I'm afraid that your test didn't really prove anything and you are in the "wild guess" mode now.
That seldom has good results.

Good luck, though. I guess the worst that can happen is you will end up with a spare ignitor.

[DSmithjr]

Yeah, that manual can be nice a specific in some places, and vague and incomprehensible in others. I tested the ignitor by removing it from the bike and checking the volts between the terminals according to the chart. I do have a multimeter that will test diodes. What you're basically testing is the voltage across the diode. My multimeter (like most) displays the voltage of a diode test in mV so you have to drop two zeros and add the decimal point to get the numbers in the manual which are just in volts. In most cases we're talking very small numbers like 0.5v to 1.2v.

My confusion with the test is that the manual only says to test the volts between the terminals; it doesn't say what needs to be done if the numbers don't fall within the listed ranges. For most of the tests, I get the "out of range" or just the 1 on the left side of my screen. And for 10 of the test, I got ratings from 1.4 -1.5 which were above the suggested range. The problem is, I don't what this means. My initial conclusion is that the ignitor is bad, but this might just be wishful thinking because I really what to know what's wrong with this bike. Some further testing might help me to reach a more definitive conclusion.

[alantf]

As a retired electrician ................Just a thought!........... If you remove the ignitor from the bike, then the battery is not connected (right?).........So how can you measure voltage between terminals when no voltage is present? Measuring resistance or some such seems much more realistic. I know that if I inadvertantly set my meter to the wrong scale (e.g. voltage, when I want to measure resistance) I get meaningless fluctuations (such as 0.4 etc, like you got) when the meter can't do what it's supposed to do. Could this possibly be why you're getting "silly" readings?

[Easy Rider]

Originally Posted by alantf

So how can you measure voltage between terminals when no voltage is present?

I was going to say that too, however, for a meter to read anything, there must be some voltage present somewhere.....and some current flow through the meter.

So, while the meter may have a calibration in ohms, it is really measuring a voltage drop using an internal battery.......and it is actually current flow through the meter that makes it move.

ALL this, however, is just fluff. It doesn't make any difference if you call it voltage or current or resistance, if you are going to specify readings with a specific meter, using a (possibly) unique test mode.

Testing solid state devices with a meter is a tricky subject 'cause different meters have different internal batteries and different internal resistances and meter sensitivities. A "good" diode can give you different readings, depending on the meter and the scale being used.

Maybe that's why they are so specific with their test requirements. Their use of the term "voltage" for a static diode test, however, is unconventional at best.

[DSmithjr]

You're correct, Easy. With a multimeter set on diode testing, you're essentially putting a small charge to one end of the diode and checking the voltage drop at the other end.

Check out this site to find out everything about diode testing: http://www.allaboutcircuits.com/vol_3/chpt_3/2.html

The issue here is not really the odd testing results (although I'd love to have a good ignitor to test and see if lives up to the manual's standards) it's more an issue of do those results really mean anything? The manual doesn't say what to do with a CDI that's not to spec. So okay, the diode switch isn't working properly, does that mean the CDI is bad and the bike might not start? :??: Most of the people I've talked to have told me that you cant' really test a CDI, and that if the CDI is bad, it's bad. There's no such thing as a semi-working CDI. My confusion is that half of the people I've talked to said that if I have a spark, it's not the CDI, and the other half have told that even if I have a spark, the CDI could still be bad.

At this point, I guess dropping $60 on a CDI off eBay isn't too bad. When it gets here, I'll be able to check it to see if it lives up to the books standards, and, of course, I'll be able to put it into the bike and hopefully get it running. I'll report back when I have the new CDI in hand.

I should also point out that I've conducted most of the other ignition tests in chapter 6 and the everything else is according to spec. This too leads me to believe that if I do have an ignition problem, it has to be this CDI. However, I don't know if my problem is even something to do with the ignition. I have compression and fuel (mostly in the form of starter fluid) so where else would I look besides the ignition? :shocked:

[Sarris]

To test a CDI unit, you really have to charge up the internal capacitor and test the discharge voltage. Low voltage means worn out.

This is not something you want to do at home, as it's a real panny pisser to get shocked by a CDI unit. (Don't ask how I know).

Cranking and no start eliminates all the safety switches in the circuit (as they disable starter motor circuit), but it could also be an ignition switch. (not too likely)

And, It's getting fuel, right??

So.... just bite the big one and spend the $$ and get a new CDI unit. After all the BS'ing here, that's really about all it can be (95%).

:2tup: :2tup:

[Easy Rider]

Originally Posted by Sarris

And, It's getting fuel, right??

"We" don't know that for sure.

Did anybody mention opening the drain on the bottom of the float bowl to see if anything comes out ??? and having the petcock in the PRIme setting?? I think so but I've lost track.

It also appears to have a good healthy, white/blue snappy spark.......which leads me to believe that the "ignition" is not the problem unless the timing is WAY off.....and I don't know exactly what controlls that.

Thus my capitulation.

[DSmithjr]

Petcock set to Prime.

Fuel will drain from the bottom of the float if I open the screw.

Here's my thinking on the fuel issue, and if this isn't correct, please correct me. Whether or not the bike is getting any fuel at all, it should still do something (sputter, misfire, something...) when the starter fluid is applied. If I disconnect the airbox and place my hand on the back of the carb and crank the motor I can feel it sucking my hand in. The motor is pulling in air. I can also place my hand on the exhaust pipe and crank the motor and feel the air being pushed out. I can literally see the motor pulling in the starter fluid vapor when I spray the fluid while cranking the motor. So if the starter fluid goes in, gets compressed (compression test show good compression), and the spark plug fires, something should happen. A pop, a sputter, a shutter, something.

This is the only reason I'm thinking spark. I'm making the assumption (I know what that means) that a bad CDI is sending out incorrect timing information and thus the no start issue. Maybe the spark is happening on the exhaust stroke??? I don't know, that's why it's so frustrating. A compressed mixture of starter fluid and air should ignite if the spark is working. When I say the bike does nothing but crank, that's exactly what I mean. Crank,crank, crank, crank... nothing. It's like there no spark plug in there at all.

Also, if I remove the spark plug and cover the hole with my finger and crank the motor, it will blow my finger off the hole and I can see the fuel vapors escaping from the hole.

If the bike would just sputter on the starter fluid and then die, I would assume it to be a carb/fuel issue. But the lack of any life what-so-ever has me thinking it's a spark issue. Is my thinking here incorrect?

[Easy Rider]

Originally Posted by DSmithjr

Whether or not the bike is getting any fuel at all, it should still do something (sputter, misfire, something...) when the starter fluid is applied.

Is my thinking here incorrect?

I'm pretty sure we have discussed the fuel issue before. It is possible that it is getting way too MUCH fuel......and yes, it won't even pop if that happens.

The church is 4 blocks that way >>>>>
I suggest you ask Him !!