Ignition Timing and the CB550

Last week I set out to adjust the ignition timing and gap the points but during my gapping procedure I noticed that there was some pitting on points 2-3. The pitting was significant enough to hinder a proper gapping width. I filed down the peak on the top point but the bottom point had a seriously deep pit. There was nothing I could do to remedy it so I decided to check out how much new points were going to run me. I also figured I might as well get new condensers since I was replacing parts anyway.

But I started to think that instead of buying two new sets of points and a new pair of condensers, plus a dwell meter and a timing light I might as well just get a Dyna-S electronic ignition and save myself the future maintenance.

Currently, there is much debate on the SOHC forums concerning the advantages and disadvantages of the Dyna-S. My opinion is that much of the argument against the Dyna-S has to do with it’s price. The explanation for the dispute against the Dyna-S centers around it’s 20 year old technology sold at the same price it sold for 20 years ago. Honestly, I don’t care how much it costs. For a few more bucks I’d rather have the Dyna-S’s convenience over points and future point maintenance.

I found a great deal at Z1. http://www.z1enterprises.com/detail.aspx?ID=437

Should be here by next weekend. Okay, let’s take out the points plate!

The points plate is held down by three screws. Step 1. Remove screws and throw them away. I have some stainless steal allen bolts to replace them with.

34 years old. I’m not gonna bother putting those back in.

Shiny new allen bolts and washers.

Step 2: remove center bolt.

Step 3: remove washer thingy.

The whole thing will come off, but I only need to take off the points base plate, the advance assembly goes back on.

Pretty clean in there.

The advance assembly. I’ve already read through the Dyna-S installation manual. This little guy will be used with the new electronic ignition, hopefully without any modification.

That’s it. Just have to unhook wires from main wiring harness (under seat) and wait for my part to come in.

Man, its such a blast working on motorcycles.

Clymer Manual Typo

My CB550’s breaker points need to be adjusted before summer riding. I started this morning but didn’t get to finish due to lunch and a light drizzle outside. What I did discover was a small typo in the Clymer Repair Manual. The point gap is indicated as .016 inches which translates to .4mm, but evidently this basic math has eluded Clymer’s copy editors. Hopefully their 21st edition will reflect an accurate metric conversion. I tried to find a contact email address for the publishers to let them know, but my google-fu skills must be lacking this morning. I can’t seem to find one.

More on this tomorrow.

Replacing the ground wire

I had the seat and the tank removed from the frame this morning to accommodate the valve adjustments. In the process I noticed something odd (as I usually do). I noticed that the green ground wire that connects to the frame was exposed in multiple places due to melted insulation. I had either never noticed before or the exposed ground was relatively new.

I’ve mentioned before that I always feel a bit like an archeologist when working on this bike. I begin to notice strange things that the previous owner did. Or perhaps the previous, previous owner did. The ground cable is no exception. It wasn’t wrapped in with the rest of the harness. It was running along side it.

This burnt out ground could explain a lot of things. Perhaps it was the root of my non-blinky blinker problem?

Needless to say, I cut it off as close to the main harness as I could so I could splice it with a better piece of wire.

I also noticed that the frame were the other end of the ground connected was particularly oxidized and rusted.   

I had never considered looking here or cleaning it up until this morning. I hit it with my dremel rotary tool with a wire brush bit. It took the rust off in seconds and exposed some nice clean steal for my ground connection.

All in all a good morning, and I’m fortunate to have stumbled on the ground wire issue. Clearly, a closer inspection is due tomorrow.

Summer Valve adjustments

The cold and the rain are behind us now and it’s time to run some basic maintenance on CB to prepare it for summer riding. I started this morning with a simple vale adjustment.

Popped the tappet covers off.

I slid the feeler gauge between all the valves to measure the gap and they were all fine. If they were off it was by a hundredth of a millimeter. No fun.

I decided to adjust them anyway for good measure and because it was such a nice morning to be outside wrenching on the ol’ bike.

Intake valves (rear) are .05mm gaps. Exhaust valves (front) are .08mm gaps.

All done.