CT90 Restoration Adventures

Posts

Options for Honda CT90 Paint

March 29, 2017

Given that most CT90's you come across are over forty years old they all tend to have a few battle scars and faded paint and show their age. In some ways I like the look of an older bike and think it adds character, but sometimes the damage is such that you really need to remove the rust or fix the damaged plastic and apply a new coat of paint. If you look hard enough you can find sources where you can purchase paint in the original colors or take color codes to your local automotive paint supply house and have them mix you up a pint, but if your like me and like to keep the cost of your project under control, you might look at the following paint options for your CT90 or CT110. I have also recently updated this post to include a listing on Honda Paint/Color codes at the end of the post.

Simple CT90 Valve Spring Compressor

March 28, 2017

If you do ever get into doing work on your CT90's engine one thing you will be faced with doing at some point if pulling the valves. I cobbled together a simple valve spring compressor using a C clamp and a piece of thick walled aluminum tubing I had setting around my garage. I took a piece of the aluminum tubing about 1 1/2 inches long and cut an opening in the side of the tubing about half way through and about 70 percent of the length. The tubing was a little over an inch in diameter and had about a 3/4 inch inside diameter.

Simple CT90 Valve Seat Check/Inspection

March 28, 2017

One of the best things you can do to your CT90 is to make sure your valves are seating and sealing to ensure that you have adequate compression. If you have your head pulled off the engine an easy way to check how well your valves are seating is with a small LED light. In the picture below I am holding the light I use and it was a cheap LED light that has a flexible gooseneck that makes it easy to stick into tight places and is a pretty common light you can find usually on the counter at your local auto parts store.

Repairing CT90 Plastic Covers and Air Filter Assemblies

March 28, 2017

Most of the time when you pick up an old CT90 the plastic covers or air cleaner housings are either missing or in need of repair. If you have the money new plastic's are readily available, but if you're cheap like me and not to picky you can possibly repair these parts to a serviceable condition. I'll describe the process I followed and hopefully it will enable you to salvage some of your old plastic parts. With this approach I use I need a seperate plastic cover or air filter assembly that has an undamaged section that is the same as the section I am trying to repair on the damaged plastic. This usually isn't a problem for me as I have several CT90's, but you may have to borrow a good part from a buddy. For this example I was trying to repair part of the air cleaner on one of my 1971 CT90's and the picture below shows the part to be repaired on the left and a good part on the right.

Dealing with Old Hard Rubber CT90 Carb to Air Cleaner Boots

March 28, 2017

I have had a couple of CT90's where the rubber boot between the carb and air cleaner and also the rubber elbow in-between the end of the air cleaner and the rack on the back of the bike have been almost rock hard and very difficult to deal with when trying to disassemble or reassemble these installations. I have found that if I take a hair dryer and heat up the rubber that it will become pliable and enable easier removal or installation. The softening effect is not permanent and the rubber will go back to being rock hard when it cools, but it does make things workable until you have a chance to go out and buy new rubber boots. I have mad another post on a permanent way to soften up old rubber parts at this link that works very well and recommend you take a look. Helpful Links (Shop Manuals, Wire Diagram, Model Information, etc.)

Figuring out wire colors on a CT90 stator when colors have faded or are not present

February 05, 2017

I have a 1971 CT90 I am working on and had an interesting electrical problem when I went to reattach the connector from the main with harness to the wires coming from the stator within the crankcase. While the one wire for the neutral switch was correctly colored, the other three wires had a cloth overboard and did not have any color. The answer to how you can figure out what the colors should be on a stator with faded colors can be found by joining the Honda 6 Volt group on Facebook. In the file section of this group, John Pardue was kind enough to share a very simple test you can perform that will identify what wire is what color. Here is a link to that file in that group, but you will most likely have to join which is very worthwhile as there is a lot of great information shared. The Pardue Brothers web site also has a lot of useful electrical related information and products to help with your CT90 restoration project. Helpful Links (Shop Manuals, W...

Soldering a Wire

January 12, 2017

A lot of times when you pick up an old CT90 some part of the wire harness may be damaged and need to be repaired. While everyone who works in their shop or on bikes and vehicles knows how to solder to some degree, I thought I would provide a little electrical help and share how I go about soldering two wires together to repair a wire harness. The first thing I will say is that if you plan on bringing old CT90's back to life on a regular basis keep an eye out for old partial wiring harnesses and pick them up when you can. Being able to salvage sections of wire in the right color and with a pin or socket at the end always makes for a much easier and cleaner repair. Some people may ask why not just use a crimp style butt connector to join two wires. While a butt connector would work and be functional, it's not that clean and over the life of a bike I feel a nice soldered joint will hold up much better and less likely to give you a problem when your 10 miles up an old...