Need Some Serious Help

[newbikekiller]

Yo!
I'm new here and I have just one question so far.

I bought my 1985 CR500 w/o spark. And it still doens't have any spark.

I will go through what I've done step by step

- The ignition system came to me complete, but not working
The previous owner gave me a brand new honda original ignition coil to try to get the bike working so I put it in
Still no spark. Since then I have bench checked the unit and it is indeed good. I have also tried to switch to the old ignition coil (it tested find too, but still no spark)

So I checked the resistance ratings on the stator and pulse generator. They were both fine so I took took a peek at the stator, rotor, and pulse gen to determine their physical condition.
It all looked fine except on of the mounting tabs on the aluminum backplate for the pulse generator had broken off. It had been fixed by a the previous owner with some JB weld, put it didn't stick.

So it seemed like a good idea to me at the time to glue the mounting tab back on the aluminum backplate with JB weld to see if
that was the problem. I don't think it was because I got things lined up pretty damn well, put it was still a no go.

I looked in my CLYMER's manual under the ignition system and it did not have any specifications to check the condition of the rotor or the CDI.

Since the previous owner mentioned the CDI I checked e-bay for a good used unit. I found one and installed it on the bike temporarily. It didn't work, and my old CDI looked a little better, so I just stuck my old CDI unit back on (to check one thing at a time).

So I bought a new used aluminum backplate, stator, and rotor (sometimes called a flywheel). They all looked to be in good condition so I tested the resistence for the pulse gen and stator on this set and it was good. I installed it and crossed my fingers. But it was still a no go. I tried to take off the kill switch too, but still no spark, I have since then tested the kill switch and found it to be good. I tried to use the CDI I bought off **** with this setup, still nothing.

I have checked the dark green ground wire that makes contact to the frame behind the ignition coil, the only ground wire in the whole setup, and have found it to be good. I have also checked that this wire has continuity all the way to the engine, it does.

Any hints/suggestions?

One thing worth mentioning is that during the test process the rotor has been about 1mm off the shaft. This is because I don't have an impact wrench right now, and It is a pain to pull the rotor if I need to if its really tight on the shaft. Could this be the source of the problem?

The whole engine and frame was painted pretty sloppily, and they even sprayed right over the rotor assembly. could there be a ground there that got messed up or something? I'm really at my wits ends with this thing.
:yikes:

 

[Ol'89r]

One thing worth mentioning is that during the test process the rotor has been about 1mm off the shaft. This is because I don't have an impact wrench right now, and It is a pain to pull the rotor if I need to if its really tight on the shaft. Could this be the source of the problem?

QUOTE]

newbikekiller.

Make sure the woodruff key on the crankshaft is not sheared. The rotor should seat all the way down on the taper without cranking it down with an impact wrench. Even though it is a pain, you might want to remove the rotor and make sure the woodruff key the crank shaft and the taper on the inside of the rotor is in good condition. If the rotor is not lined up correctly with the crankshaft, it could throw the system out of phase.

Also, check your ignition timing with a dial indicator to make sure it is spot on. :cool:

Just my $.02

 

[newbikekiller]

bump and

The woodruff key isn't sheared

I think its just a tight fit after all these years, and the fact that the rotor I'm putting on isn't the rotor the bike came with in 85'. (So the clearances will have to settle a bit).

I'm having my friend take a look at it now :|

I'm not getting ANY spark. So I don't quite see how setting the ignition timing with a dial indicator would help anything, then again maybe I'm just flat out wrong about this.

And also, BUMP! There must be someone out there that has had a problem like this and can point me in the right direction :eek:

 

[KiwiBird]

Sounds like you've done the right stuff - remove the coil and sand the frame clean to the bare metal where the coil attachs. If he painted the frame minus the motor it may be worth checking the motor mounts for paint too - try running a ground from the motor directly to the coil ground.

 

[newbikekiller]

Great tip
I already sanded the coil ground and checked that there was continuity between the coil ground and the engine, however
:bang:

 

[newbikekiller]

Bump! I think this one gets put in the trash too soon. Is there any test I can do on output with the bike _not_ running? Is there anyway to test the CDI without having another bike?