My Dad bought this bike, a 1968 Honda CT90, when he was young; probably about 35 years ago. I pulled it out of his shed, where it had been sitting for about 10 years. It wasn't running, was rusty, and corroded. Luckily the bike wasn't missing any parts. I have never worked on a motorcycle before, or engines in general. This seemed like one of the easier platforms to start on, so I went for it.
I began tearing the bike down. This was a slow process as I continually ran into pieces I wasn't sure how to remove or I was worried I wouldn't know how to put them back on. I took a lot of pictures of parts along the way.
I got the engine out, it was nasty and surprisingly heavy for its size. It clearly had some oil leaks. I was the most worried about this part of the restore, so I set it aside for awhile.
parts were all over my garage for 2 years, but at least I labeled them!
I made a cardboard bolt holder where I labeled and stored all the bolts I pulled. It filled up a bit more than that later on. This is also about as clean as my workbench was during this process.
The naked frame. I felt like I have accomplished something at this point.
I scrubbed the engine multiple times to clean off the oil and dirt. It doesn't look too bad in the picture, but the cylinder is rusty and the paint looks terrible overall. I was overwhelmed by a sense of dread again thinking about taking it apart, so I put it aside again for about a year.
All the red parts were powder coated! A terrible picture, but they turned really great.
I got the steering stem in and front shocks in. I replaced the bearings, I had no idea what bearing races were, but after many hours of cursing at it I removed the old ones and got the new ones in. I kept the old front shocks, which are inside the front forks. It is an odd setup for shocks, but I do like the look of it.
I ended up buying new wheels and hubs on ebay because mine were rusty and a bit broken. I also put new bearings and brakes in. I used my old hub covers which contain the brakes and few others things. Putting tubes and tires on was a good lesson in patience and popping tubes. I bought 4 tubes, and luckily managed to only pop 2.
I got the handle bars on and the controls installed (for now). In this step I learned how to extract a bolt when you snap the head off. That skill came in handy later when I did the same thing to an engine bolt.
I got the front and rear breaks installed. Installed the taillight, and the rear shocks. Surprisingly uneventful, I don't think I broke anything during this step.
After the engine, wiring was the second most stressful part. I think i quit working on it for a couple months because the first wiring harness I bought was wrong and I gave up. I found one on ebay in Argentina which had all the correct wires! It was then that I found the light controls on the handle bars were wrong and I had to pull that out and find a new one.
I'm not sure how this happened, but I wired everything correctly on my first try and the lights worked.
The day finally came where my greatest fears were realized. I printed out schematics for the engine, made a numbered lists of all the parts, and got bags and storage containers ready. I also found a video of the engine build online and followed it backwards.
All the big parts are in bags and all the small parts are in the divided containers on the left. I also drew the engine sides on some cardboard so I could place the case bolts in the correct spot. Sorry, no picture of that.
Here are the cleaned crank case side and covers! One side of the crank case had to be repaired, there was chip in it that I believe was the cause of some of the oil leaks. I scrubbed them down, sanded the outsides and the painting began!
Many many coats of paint later they turned out pretty good. Etching primer, high temp primer, high temp color, high temp clear. Three coats of each.
A little jump ahead. I got the bottom end rebuilt. The assembly went pretty well, I broke one extremely important bolt, but I was able to extract it and replace it before the locktight took hold. Foolishly, I thought I was going to have the engine done soon. Turns out getting the cylinder bored and powder coated takes a month and half, who knew?
I got the top end done! It looks pretty good I think. I tried to polish the side cover, it's almost good enough to see me awkwardly laying down to take this picture.
I made this beautiful collage to give a comparison of the engine before, during, and after.
I got the engine on the frame. There are only two bolts that connect it.
I got a bit excited and didn't take as many pictures as I should have. I got several things chromed: cargo rack, headlight ring, and skid plate thing. I also tore off the seat and had a new one made. I then tried my had at rebuilding a carb. After a massive failure, I found a replacement carb on ebay for $20. I felt a bit foolish since I spent $30 on a carb rebuild kit for the old nasty one. The glorious moment of starting it for the first time was quite the rush!
Finally, here are a few pictures of the completed bike. It took me almost 2.5 years to finish, but I think it turned out pretty well. I have already pulled the engine out and taken the top end off a second time to try to fix an oil leak. There is still a slight leak somewhere that I haven't tracked down yet, but it does run great. It maxes out at 40 mph (43 with a tail wind) so it's great for putting around town.