Honda CT90 spark advancer writeup (1 Viewer)

[valentine]

So here we go. I'll see how many posts I can turn this into.

Here's the points and the backing plate. You don't need to take the points off to take the points backing plate off you just need to take the points lead off.

There are just two screws holding the points backing plate in. The bottom screw you just need to take half way out, the top you take all the way out.

The bolt in the center of it all needs to come out too. It holds the advancer in place. You can take it out now, or after you take the points backing plate off. I put a 14mm wrench on the generator center nut to hold the points "cam" from turning while loosening the bolt.

The little notch that I circled is a timing notch. Right under the gasket by the bolt hole is another notch that you line it up with. I put a red mark on the gasket in the approximate location.

The backing plate screws were almost stripped out as you can see in the pic. Luckily I had an impact screw driver, I wouldn't have gotten them out any other way. I went to the hardware store and bought new stainless steel allen head screws to replace them with. I believe they are 5mm x .8 pitch.

 

[valentine]

Here's what it looks like with the points backing plate off. Since I already took the center bolt out, I pulled the advancer strait off the shaft. It came off very easy.

 

[valentine]

Here you can see the notch in the back of the collar where it lines up with the pin on the cam.

Here's a pic of the cam pin. There's no way you can put it back together wrong. ;p

 

[valentine]

Here's the two reference points that were on my '70. As long as you make sure they're lined up when it goes back together, you're not going to be 180º out.

 

[valentine]

Pull the "c" clips on the weights. It's best if you have someone help hold those little suckers from spinning when you're trying to take them off. I had Nicholas hold them with an awl.

You have to lift the weights and the shaft up at the same time, otherwise they'll bind and you won't get anything undone.

I left the springs attached so I'd remember which way the springs go.

Off it comes.

Here's the shaft that needs greased. Mine was completely dry. I didn't wipe it at all before I took the picture.

 

[valentine]

Here's what the inside of the points lobe looked like.

 

[valentine]

I greased it up, put it back together. It was super simple.

Time for a beer.

 

[valentine]

Put back on.

Original

Replacement.

 

[valentine]

Next step is points backing plate and hook up the wire to the points. I lined up the marks that I showed in the first pic, then static timed it. It was perfect.

 

[thorvald]

cool, nice writeup

 

[Hugh Heifer]

Uh oh. My cam came off with out taking the arms off I think I had some chit buggered in there.