Timing Light Plug

[cfairweather]

It is hard to get a good picture of a clear item, but here is the latest version and maybe the final one. I need someone to test this quickly for me. If you test it, you can keep it. I have a volunteer. Thank you.

DSCN4798.JPG (111.92 KiB) Viewed 442 times

[tlbranth]

How about an elbow at the top with an angled mirror? It's worth the effort, too, to, one at a time, clean the timing marks with degreaser on a q-tip and put paint in the marks. They be a bugger to see without paint.

[ericheath]

Rednax60’s method would work, but is tight to see.

I used a plain plastic elementary school protractor after getting belts lined up at T1. Then marked every five degrees on the belt cover backing plate. I used an old chisel (don’t tell my Dad) to leave a small visible mark that would last. I had an old school timing light. Cam moves at 1/2 of crank speed, so 5 degrees on the cam is ten regress of crank rotation.

With the waste spark, you can see a variation each time it lights. I’m guessing that is from the loose and tight nature of the belts or the wobble of the cam. (I never checked the light with my PowerArc ignition on the crankshaft.

I have a video of it somewhere on here. [/Video]

[cfairweather]

I have still been working on the timing plug and I think it is close to working properly. Mark did some testing with the design on the right and we learned some things. First, the plug needs a lens, because the plug must not release the pressure inside the engine or the oil will splatter out. The other thing I learned is the curve on the bottom and blocking the gap on the right side helps keep splatter to a minimum. So, although the first design attempt did not work, we learned a lot from the test.

So, how do I put a lens into this plug? I went searching for sight glass, but found this would make the cost go up a lot, so I gave up on this approach. I decided to just make the plug with a lens using the plastic, but the challenge was to make it clear enough to see through. I designed the lens to be only 0.5 mm thick to make it more transparent. Then, I tried polishing using a multi step process that people typically use to polish plastic and it worked pretty good; however, it took forever to make it look acceptable. Then the solution hit me and here are the amazing results:

The one on the left has a lens and the one on the right doesn't have a lens.

DSCN4827.JPG (112.6 KiB) Viewed 284 times

I will have one of my project bikes in a state where I can test the plug in a few days.

[pidjones]

Acrylic seems to polish the easiest. That's what I made mine from. I just put a small blank hole in the center as a fiducial for timing.

[pidjones]

This is what I've used since ~2017. It's been bouncing around in my bike tool drawer since, and could use a re-polishing.

acrylic sightglass.jpg (127.11 KiB) Viewed 247 times

[cfairweather]

This morning, I got one of my project bikes to a point where I could start the engine and test the latest plug. The good news is hardly any oil enters the viewing area. When I used my timing light, I did get a lot of light reflections from the lens, so I will need to see if I can improve that issue. Now for the exciting news: I am adding a feature to this plug that is unique and I think you will find it very helpful. My limited testing this morning tells me that my idea will work great, but time will tell. The plug will have a 3mm LED imbedded into the plug which will serve several functions.

Option 1: Flashlight mode. The light can simply provide light directly aimed at the flywheel so you can statically time the bike without having to shine a light into the hole. Clip on to the battery for this option.
Option 2: You can use this light as your static timing light. Makes it easy to see exactly when the light comes on because it is right in the hole.
Option 3: You can use this light to dynamically time the bike without a strobe light. More testing is needed on this option, but I believe it will work fine. I think this will only work when using an electronic ignition and have only tried it with a Dyna clone. You connect it just like you do with static timing.

[cfairweather]

Here is a picture of my first plug with a light inside.

DSCN4828.JPG (213.73 KiB) Viewed 204 times