A cm400 and a youngster

[Cafebikes]

Hello all you grease monkeys!

I've been lurking the threads on do the ton for a while, and decided to finally get a bike to cafe. But being 16, the funds are quite limited. In Utah, cb's can get up to about 1000 dollars for a non running bike. That's waaayyy too expensive for a bike that who knows what's wrong with it. Please point something out if you think there is something wrong. This is a learning process for me and I want your guy's feedback.


So I decided on getting a cm400. They are a lot cheaper. I know the frames aren't the best but I was determined to make it work. I ended up on one that was running and all original parts were there except for the headlight, it had been replaced with a funky looking one. The only problems were the starter motor not working, a leaky carb issue and the clutch switch and front brake switch don't work. Anyone know where I could get those switches?

I got it for 750. This is all in the past, I've been working on the bike for a while and will catch you guys up to speed.

When I first got it I wanted I just make sure I got it running good before dismantling it. I got the starter issue fixed in a couple minutes. It was a bad switch. The solenoid and motor were still good. I spent a day cleaning carbs and fixed the leaky carbs. The float needles were stuck pretty good. It had been just pouring out fuel. It ran well after the carb clean up and has some pep for a smaller bike.

Here are some pics of the day I got her.

And some after I started tearing her down.

I modified a headlight that I got from a friend a put an led headlight that is originally for cars. It has low and high beams. It's bright! I also started cutting off tabs and smoothing up the frame.

I got some parts and started seeing how they looked.

I got a cb360 upper and lower triple off eBay. It has the same bearing races and swaps right in. It has 33mm fork holes so it fit right in. The original upper triple is stamped and I couldn't lower the triple on the forks. With the cb360's I can.

I welded some square tubing to the frame to allow me to mount a seat. It helps continue the lines of the tank so a fiberglass seat would look good.

I welded a bar from the frame to attach the stock battery box. And later welded on a gusset. New lithium batteries are expensive and these older ones can still be bought at the store as they are cheap. So I wanted to be able to mount it to the frame. It can't fit under the seat so I thought this would be an ok place to mount it. Let me know what you think of it.

My fingers are tired so I am done writing for today. More to come!

 

[CafeDude]

Cool project. Before welding, clean the metals real good. Don't weld over paint. And turn up the heat on the welder, those welds look a bit cold.

 

[Cafebikes]

Cool project. Before welding, clean the metals real good. Don't weld over paint. And turn up the heat on the welder, those welds look a bit cold.

Yeah, I had to redo the welds later, I wire wheeled the frame to get the paint off to do it, and turned up the welder a lot.

 

[wahvtec]

if you ever get bored balled up aluminum foil and marvel mystery oil will clean up those spokes alot! Just a trick I've used a few times. Cool bike to start with.

 

[Cafebikes]

if you ever get bored balled up aluminum foil and marvel mystery oil will clean up those spokes alot! Just a trick I've used a few times. Cool bike to start with.

thanks! As I've been cleaning them I have been wire wheeling them and repolishing them. They were pretty rusty by the nipples. But thanks for the advice though! That trick will work well on the rims I think.

 

[Cafebikes]

Here is an update

I then started on my fiberglass seat. Here is the mold.

I had to make it a little square on the back so the stamped ends of the frame didn't poke out weird.

Test fit.

After adding more glass and body filler.

I bought some old schools rear sets and shorty emgo mufflers from dime city cycles. I used the stock rear brake linkage and shift lever to hook up the linkage. The rear sets are mounted on the passenger peg spots. I'm 5' 11" and needed that extra leg room. The setup fits me well.

I don't have pictures but I welded a mount for the tail light. I need to cut a hole in the seat to be able to accommodate the tail light.


Here is the product before I started taking everything apart. It had a good stance I think. And the lines of the tank carried well.

I still haven't finished updating everything so I will probably finish up later today.

 

[Cafebikes]

I got everything off the bike and started to clean everything.

Ive been working on getting everything down to bare metal. I am still in this process currently.

I got the front tire off the rim with some screw drivers and took apart the entire wheel.

I started engine teardown. I have the cb/cm400 shop manual and I'm going to check all of the clearances and tolerances.


The head came off no problem but the cylinders were pretty stuck on pretty good. I heated the gasket and use some penetrating oil. I used a wide piece of wood on the bottom fin towards the base of it and hammered upward, it finally gave way.

I had to buy a flywheel puller to to get the flywheel off.

I used a penny to mash between the clutch and crank gears. The penny is soft metal so it doesn't damage the steel gears. I also made a tool to get the clutch lock nut off. It isn't a normal hex nut. It's a circle with notches in it so I got a socket the same size and cut out some pieces. Here's a picture of it.

After the flywheel and clutch were off everything else was removed easily. I used the same technique to split the cases as I did to get the cylinders off. After that everything came off with relative ease. The engine is was actually pretty clean inside. Looked like it had always been up to date with oil changes.

Now is the stage of cleaning and painting the engine. I have been soda blasting everything. I'm going with vht gloss black for everything and then the side covers and valve cover polished. I might sand the edges of the fins to bare aluminum.

Now I am up to date and working on finishing painting the engine. I got the oil filter cover painted as a test piece to see how well the paint sticks. It turned out pretty good!

My friends dad has a shop and I am going to be able to powdercoat the frame and all small parts. All the aluminum on the frame I am planning on polishing.


Now I am up to date. The rest of the engine should be painted this weekend and the next week.

 

[8ighty1ne]

awesome! attention to detail. i went a different route with the cm400...im getting ready to tear this apart again for "stage 4".. 8)

 

[Cafebikes]

Nice project 81! What else is there to do? That is one good lookin ride! I really like bobbers too. I hope sometime in the future I can find a Harley Davidson iron head to hardtail.

 

[Cafebikes]

I got more of my engine painted. It's seems to be sticking really well. I got the cases done and I ordered a new gasket set, oil filter and hondabond. So after I bake the pieces I can go ahead and reassemble the engine.

 

[Cafebikes]

I forgot to take pictures when the bike was assembled but I made an electronics pan that goes under the seat that the fuses and solenoid and rectifier stuff are mounted on.

Any ideas on paint for the tank and seat? I was thinking either a classic honda red or a gloss white. But I can't decide.

 

[98kellrs]

Maybe paint it with a white undercoat first, and then you can decide if you want to spray a red over it or if you like the white?

 

[8ighty1ne]

put it together, the color will come to you if you cant decide. then take it all apart again! looks good so far

 

[Cafebikes]

Thanks for the input! Hopefully I can decide when it all comes together.

 

[Cafebikes]

I was cleaning some more part today and I soda blasted my honda tank logos. I thought they cleaned up pretty nice. I might just keep them this way.

 

[Cafebikes]

Are eBay rear shocks any good? If I can't get any good ones I'll probably just keep the stock ones. The ones on dcc are pretty pricey.

 

[warpt_99]

The "air" ones are junk, check emgo for some cheap shocks with decent quality.

 

[oldskool]

awesome! attention to detail. i went a different route with the cm400...im getting ready to tear this apart again for "stage 4".. 8)

. If you use 2" copper to make a 3" extension for the pods it will run a lot better.

 

[Cafebikes]

Thanks warpt, I'll have to check those out! Emgo is a good company.

And thanks joonyah for the copper extension idea, I have been looking around on tuning these cv carbs and the three jets are pretty much impossible but the two jets are easier. Luckily mine is a 2 jet. I'll have to try that out.

Does anyone know of some good jetting sizes? Some that you know will work and you have tested maybe? I live in utah so elevation is like 4300 ft above sea level or something like that.

 

[warpt_99]

Jetting is going to vary, I lived in northern Arizona for a long time (7000ft elevation) and jets would have to be swapped out a lot based on temps and the elevation because the air is much thinner.