CDI?

Is the CDI toast?

No - there is a bad ground or something as the starter won't turn very well. Grounding post shows signs of tarding. Also, there is some spark even though the coil cap seems crappy.

Yes - There is weak spark. It failed for PO suddenly on the road. There is a melted-looking place in the cdi potting. It's old and why not. Also, the unit fails all the tests from the book - infinite resistance everywhere except between the two E posts.


Here's some wisdom from a forum:
"FYI, the CDI unit is known to fail unexpectedly, especially in older machines, not just Hondas but all bikes/scoots. They can also create irregular performance before complete failure. Buying a used CDI has the risk of short life, and there is no way for the backyard tech to test other than to observe a running engine before removal. There are a few clone CDI's made in China that are just as good as OEM, and are inexpensive, but shop around as the price varies.

The CH250 1985-1988 series uses an AC type CDI, where the 89-90 use a DC type, and they are not interchangeable. For scoots running one day and not the next, the CDI should be on the suspect list."

To tell if you have a DC or AC CDI look at the plugs. There will be a 4 connector plug and a 2 connector plug. On the 2 connector plug, if there is 1 wire then it is DC, if there is 2 wires then it is AC."

Pardue Brothers how-to on testing the CDI on a cub 70.

Another forum link with a CDI issue on a CH150 (same basic motor).

S90 Harness fix

I took some video of a harness being taken apart. This one was pretty complete, so I wanted to show how it all went together. Soon, I'm going to rewrap it with the tape I got from here.

Except for the black paint overspray, it cleaned up pretty well with Krud Kutter. Shout out to Cycle Psycho for turning me onto it.

The plastic tube was broken at the usual place and the brown wire had broken.This is where the turning of the front forks strains it.

Here is the video:
http://youtu.be/Jn5-EVuyVmM

Wiring cleanup

I took a lot of pictures of this process so I could cram it all back together where it came from.

CT200 Carb Rescue

 Here's some pics of rescuing a ct200 carburetor with a stuck slide. I got this cheap on ebay because the previous owner had given up getting the slide out. 

If you look closely at the stands for the main and pilot jets, you can see where I got a little overzealous with the torch as I was trying to loosen the main jet. Patience is key with these because they are so easy to break. Don't pry on them with anything tougher than a chopstick. Matter of fact, a chopstick is the perfect tool to get the needle jet out.

Looking at the slide, you can see where the P.O. tried to pry the slide out. Do not do this! Even in the best case, you'll score the channel the slide rides in and ruin it. I had to dremel this down to knock off the high spots before continuing. 

Don't tell anyone, but I lost patience and used another trick to get this guy loose. Ready? Ok, I used a chopstick to gently pop the needle jet out. Then I stuck a crappy harbor freight probe through the jet hole and up against the bottom of the slide. The probe was slightly bent at the tip, so it didn't hit the slide right at the hole where the needle comes through. It hit it just off of that. I held everything in place and after another shot of silicone lube spray, I tapped the whole mess on the table and it popped the slide out. Not perfect or professional, but whatevs.

Some shots of the slide. Looks like it wasn't damaged. I'm glad this one was salvageable because the threads pictured here are clean and unstripped. One of the weak points on these carbs is these threads.

I forget what these probes are called, but you can see one with the orange handle in the background. HF sells a set of five for very little and they do come in handy.

Ugly-looking slide, no? Some of it is probably from hitting it with the torch and alternating silicone spray. You can also tell where I ground down the high spots with a dremel. The high spots were from the P.O. prying on it with a screwdriver and I didn't want them to score the carb body on their way out.

Final Drive Oil Change

More crappy pictures. Final drive is such a pain on these. I used 30-weight oil, but when I've run it around the block a few times, I'll probably use 80-weight like the forums recommend.

Top End Assembly

Some crappy pictures of the top end assembly.