Weak spark on point for 1-4

[Guest]

Hey everyone,

I've been having what I thought were fuel issues with the bike recently till I realized that its just cylinders 1-4. The spark plugs on those cylinders were fouled and 2-3 looked fine.


A few months ago I got new points, set the gap, and did the timing.

I tore back into it today and noticed that the spark looks super weak on point 1-4. My question is, could this be the coil? If so, how do I test? I have a multimeter, but I've never used one before. Can someone lend me some instruction on how to test the coils? Thanks in advance!

[chuck hahn]

I would first regap the plugs and see what the spark looks like then. If no change, I would take a screw driver and remove the plug gripper thing inside the boot. Look in and you should see a screw driver slot in there. Unscrew it and dump the contents into your hand. the ceramic thing is a resistor..get rid of them!!! Get some heavy copper rod or similar thats close to the diameter of the resistors and cut it to length.

Get rid of all of them actually. 1 and 4 will not have a spring...2 and 3 will. on 2 and 3 put the spring in first then the metal replacement. Screw in the plug gripping thing and be done with the resistor crap forever.

[giganticflying]

Sorry, I think I need to clarify. The spark is weak on the 1-4 point itself. It doesn't seem to be as nearly bright as the 2-3 point. I've tried to sand down the contacts a little but its still pretty weak.

Maybe there is a better way to put it that I just don't know about yet.

[chuck hahn]

Long as they are gapped properly is all that matters...and a thousanth difference between the two may make one arch a little. Button it up and forget about it.

[giganticflying]

Thanks for the reply. I absolutely get what you're saying about the gap and I've been as diligent as I can be about making sure my the gap is correctly set.

The connection between the repeatedly fouled plugs on 1 and 4 and the seemingly weak spark at the point is too hard to ignore though.

Can someone please lend some advice as to how to test the could with a multimeter since I I've never used it before?

Again, I have new-ish points and the timing is pretty spot on, though even during the timing the light bulb was during noticeably dimmer when attached to 1 than 2.

[chuck hahn]

Take a piece of paper and put it in the points so it doesnt go to ground. Look at what color wire is going to the point in question. take off the tank and find the coil with the same color wire going to it and unplug the wire. test continuity form the points end to the coil end of the wire.

[geol]

Chuck, If there is some spark on 1/4 then there will be continuity. Suggest perhaps the condensor associated with 1/4 is the culprit. Swap it with 2/3 condensor and see if the problem moves to that pair of cylinders. If it does, buy a new points ignition tune up set and install or go to a Dyna S. Might also start by swapping 2/3 coil with 1/4 coil (making sure plug wires continue to go to the correct plugs) and see if there is a possible coil issue.

[giganticflying]

Thanks for the advice. Those points and condensers are new, but maybe I'll try to swap the coils to see if that is the issue.

[chuck hahn]

He doesnt have a problem with spark at the plugs Goel...hes worried about the arching down at the points themselves. Points dont "usually" throw off big sparks...usually. I have had the springs bend in and cause problems with good ignition though. Arching from the spring to ground isnt good. I always make sure that after I do points maintenance the springs is straight in line like it should be.

[giganticflying]

Mostly I'm just trying to make some sort of deduction from the fouled plugs on 1 and 4, inconsistent feeling of acceleration when riding, and the point for 1 and 4 looking weaker when the contacts on the points are sparking/arching(?) while the engine is turning/idling/throttle is applied. Maybe I'll try to take some pictures later.

[chuck hahn]

Got a lot of extra length on the plug wires??? Unscrew the caps and cut about 1/4 inch off the wires and screws the caps back on. Fresh connections make for better spark...which in turn leads to better fuel burn in the cylinders.