Topic: Blue Spark On Points? - 1978 CB750F

[cowboycletus]

Hey Guys,

I did a little ignition work today and cleaned/gapped the points and set static time . The points for 2&3 were quite dirty and pitted. The bike starts and idles on three cylinders (missing number #2) but while running I can see a blue spark coming from the point for 2&3. It doesn’t do it on the other set.

Any ideas what this is from? Cheap as they are I figure I’ll just get a new set of points and replace them.

[evinrude7]

Get TEC points not the cheap ones.

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[HondaMan]

Get an entire points plate set directly from Honda. I recommend South Sound Honda online, about $80. The others are all knockoffs, and the condensors are bad, some right from the package new. That's likely what you have now: bad condensors cause a bright blue spark at the points, little/no spark at the plugs, and burned points.

[cowboycletus]

Get an entire points plate set directly from Honda. I recommend South Sound Honda online, about $80. The others are all knockoffs, and the condensors are bad, some right from the package new. That's likely what you have now: bad condensors cause a bright blue spark at the points, little/no spark at the plugs, and burned points.

Awesome advice. I just ordered the assembly you mentioned. Thanks Hondaman!
Hopefully this resolves the ongoing issue of me losing that side of the ignition.

[Deltarider]

... while running I can see a blue spark coming from the point for 2&3. It doesn’t do it on the other set.
Any ideas what this is from?

Where exactly does the spark occur? Could be a bad condenser, but, as it concerns the 2+3 breakerpoints, there's a chance it wasn't fitted cprrectly.

[cowboycletus]

... while running I can see a blue spark coming from the point for 2&3. It doesn’t do it on the other set.
Any ideas what this is from?

Where exactly does the spark occur? Could be a bad condenser, but, as it concerns the 2+3 breakerpoints, there's a chance it wasn't fitted cprrectly.

This isn’t my photo but it’ll work for the sake of the post. The spark happens between the 2 metal “points” for 2&3, as indicated in the photo.

[Deltarider]

When sparking is in between the breakerpoints surfaces, it indicates a bad condenser. When the spark is elsewhere, it could be breakerpoints fitted incorrectly.

[cowboycletus]

Good news! A new condenser did indeed fix my problem of blue spark between the points. However,
After installing the new condenser, re-gapping/re-timing, and installing a new clutch cable, I now have an awful squeak coming from the points assembly area. Frequency of the squeak/chirp follows RPM.

The bike starts at the first touch of the starter and idles well. Oil level is full. I was chomping at the bit for a test ride but I couldn’t make myself do it without understanding what that squeak is and how consequential it may be. Any thoughts?

[cowboycletus]

Good news! A new condenser did indeed fix my problem of blue spark between the points. However,
After installing the new condenser, re-gapping/re-timing, and installing a new clutch cable, I now have an awful squeak coming from the points assembly area. Frequency of the squeak/chirp follows RPM.

The bike starts at the first touch of the starter and idles well. Oil level is full. I was chomping at the bit for a test ride but I couldn’t make myself do it without understanding what that squeak is and how consequential it may be. Any thoughts?

I also had the gear shift cover off yesterday to replace the gasket.

[seanbarney41]

Try lubing the points cam?

[cowboycletus]

Try lubing the points cam?

That makes sense and would explain why I could hear the “squeak” while turning the engine by hand. I wasn’t aware of lubing the points cam/pads. Hopefully that fixes it!

Any suggestions on lube? A quick google search has suggested either dry lube or brake grease.

[robvangulik]

why would you use brake grease on points? Brakes hardly move and points go up to 10.000 rpm?
Try points grease. But I suppose everything is better than NO grease.

[seanbarney41]

I think the grease supplied in those little packs is very similar to high temp dielectric.

[cowboycletus]

I think the grease supplied in those little packs is very similar to high temp dielectric.

Unfortunately there was no grease included with points/condenser packaging but I put a little dielectric grease on the points cam and that solved my issue. Thanks guys!