CB400F First Build! College Kid's Cafe Project
- Thread starter aaron33royer33
- Start date
puddle pirate
New Member
If you are just looking for a start, all you really need is fresh fuel, power, 12.7 or better to the coils, and a ground running to the negative on the battery. You can use a charged car battery sitting outside the bike just to get proof of life. You can even use that to jump just the starter and save your leg some kicks. As far as the tank, I would buy a POR15 kit, I have used two of them and have nothing bad to say at all about them, they work.
My CB400f Build will have the starter installed, but i'm planning on running a small 6A battery so it will be kick only. Let me know if you have questions.
JT
My CB400f Build will have the starter installed, but i'm planning on running a small 6A battery so it will be kick only. Let me know if you have questions.
JT
Goodfella
Been Around the Block
I'm also an engineering student who rebuilt a cb500 in high school. I would recommend you keep the starter. It came in handy when starting it the first couple times after it sat for 20 years. It also helps when you need to check spark and timing. Are you planning on replacing the wheel bearings and the steering head bearings? Also good luck only spending $1500. That's what my budget was at the start and I spent way more than I wanted. I'll be following along and recommend you at least take a look at my thread for ideas and tips and so you can learn from my mistakes before you make them.
gordo2472003
Been Around the Block
Sonreir said:
Sonreir= always so cool, calm and collected lol
Sent from my iPhone using Tapatalk
NoRiders
Over 1,000 Posts
Good work so far....I've posted a link to my son's '78 400/4 starting up for the first time in over 15 years (last on the road 2001) for encouragement....enjoy the sound of a happy engine.
https://www.facebook.com/colin.davies.9843/posts/10201477906705684?notif_t=like
Carry on....
https://www.facebook.com/colin.davies.9843/posts/10201477906705684?notif_t=like
Carry on....
aaron33royer33
New Member
Build Updates:
Coils tested and installed
Air box interior sanded, wire brushed, and installed
New clutch spring installed
Handlebars installed with throttle and clutch
I had the carburetors installed, but then realized that I forgot to replace the aftermarket air screws with the stock ones. While the carbs were on, the fit up nicely with the throttle cable.
Notice that I have details about the airbox in the build updates.... I have seen the light and decided to not go anywhere near the emgo pods and attempt to fire the bike up with a stock setup.
To test the coils I used the coil test method described in Sonreir in the electrical 101 forum. Low and behold all of the coils worked as I saw a nice blue-white spark on each plug.
The major steps still needed to get this bad boy primed to start are gas tank interior clean, wiring, fuel wiring, and clutch.
An issue I have encountered is the clutch. I found out the lever return spring was snapped. After ordering and installing a replacement, the clutch does not really operate. The cable doesn't want to move in either direction more than a few mm. I have the cable hooked up to the lever and the lever will not pull at all. At this point, I don't know if this is an external issue like the cable or an internal problem in the motor. There is no oil in the motor right now if that would mean anything. I tried pulling the lever while shifting gears, but still nothing. Any help on this would be greatly appreciated.
Coils tested and installed
Air box interior sanded, wire brushed, and installed
New clutch spring installed
Handlebars installed with throttle and clutch
I had the carburetors installed, but then realized that I forgot to replace the aftermarket air screws with the stock ones. While the carbs were on, the fit up nicely with the throttle cable.
Notice that I have details about the airbox in the build updates.... I have seen the light and decided to not go anywhere near the emgo pods and attempt to fire the bike up with a stock setup.
To test the coils I used the coil test method described in Sonreir in the electrical 101 forum. Low and behold all of the coils worked as I saw a nice blue-white spark on each plug.
The major steps still needed to get this bad boy primed to start are gas tank interior clean, wiring, fuel wiring, and clutch.
An issue I have encountered is the clutch. I found out the lever return spring was snapped. After ordering and installing a replacement, the clutch does not really operate. The cable doesn't want to move in either direction more than a few mm. I have the cable hooked up to the lever and the lever will not pull at all. At this point, I don't know if this is an external issue like the cable or an internal problem in the motor. There is no oil in the motor right now if that would mean anything. I tried pulling the lever while shifting gears, but still nothing. Any help on this would be greatly appreciated.
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aaron33royer33
New Member
Just had a nice relaxing morning examining the wiring harness off of the bike. My Guatemalan roommate made some delicious coffee from back home that fueled the past few hours ;D. Took a lot of the wrapping off and just started to trace the wiring diagram to get an understanding for it. I labelled connections and started to remove the components that I won't need to start the bike (lights and gauges). I don't have the stock starter/kill switch for the right hand side, but the bike came with an aftermarket 3 position and push button switch that I will use for the starter and kill.
Results:
- I am deciding to use the original wiring harness off of the bike. I think it's easier for me to delete unnecessary items as opposed to creating necessary ones from scratch.
- I am keeping the starter, thanks to the persuasion from you guys. It would probably be harder for me to remove it than to keep it at this point anyways.
- No lights will be wired for the start. I don't think this will be a problem based on the wiring diagram, but if I am making an oversight, please let me know!
I'll be buying a battery in the next few days. I know there are options and pros to cons to everything, but if anybody has first hand experiences or recommendations, I would definitely appreciate it. Focus here is cost and simplicity.
I am going out to start the rust removal process on the gas tank today. I'm going to try the conventional evaporust and sit method to see what kind of results that yields. Just trying to think about what to use to stop up the petcock hole....
Anyways I really appreciate all of the feedback and advice thus far, and I hope everybody out there is having a chill weekend.
Results:
- I am deciding to use the original wiring harness off of the bike. I think it's easier for me to delete unnecessary items as opposed to creating necessary ones from scratch.
- I am keeping the starter, thanks to the persuasion from you guys. It would probably be harder for me to remove it than to keep it at this point anyways.
- No lights will be wired for the start. I don't think this will be a problem based on the wiring diagram, but if I am making an oversight, please let me know!
I'll be buying a battery in the next few days. I know there are options and pros to cons to everything, but if anybody has first hand experiences or recommendations, I would definitely appreciate it. Focus here is cost and simplicity.
I am going out to start the rust removal process on the gas tank today. I'm going to try the conventional evaporust and sit method to see what kind of results that yields. Just trying to think about what to use to stop up the petcock hole....
Anyways I really appreciate all of the feedback and advice thus far, and I hope everybody out there is having a chill weekend.
Attachments
NoRiders
Over 1,000 Posts
Good start on the wiring.....it's my weakest point, so I'm pleased my son is an electrical engineer to help.
Interested in the tank de-rust process as I have the same problem to solve......I have some vinegar and think I'll slosh around some nuts/bolts/nails to see how it goes. I really need convincing a liquid tank liner won't gum things up in the long term??
Could you cut a solid rubber disc to blank off the fuel outlet and use the retaining nut to seal it? Or use heavy duty polythene with the nut instead?
Interested in the tank de-rust process as I have the same problem to solve......I have some vinegar and think I'll slosh around some nuts/bolts/nails to see how it goes. I really need convincing a liquid tank liner won't gum things up in the long term??
Could you cut a solid rubber disc to blank off the fuel outlet and use the retaining nut to seal it? Or use heavy duty polythene with the nut instead?
puddle pirate
New Member
Good luck with the tank cleaning. Vinegar and "the works" toilet bowl cleaner will both eat or remove the rust pretty quickly. The problem I had was the instantaneous flash rust. I ended up going the POR15 route on two motorcycles, no complaints so far. You can get a small rubber plug from a hardware store for the bottom, and for the top I just used some two inch electrical tape.
As for the battery, on my GS650E I went with whatever battery would fit in the space from Walmart and had around 210 CCA. If it went bad inside a year I can take it back. The CB400f build will have a smaller battery and be kick only. I haven't quite narrowed it all the way down.
As for the battery, on my GS650E I went with whatever battery would fit in the space from Walmart and had around 210 CCA. If it went bad inside a year I can take it back. The CB400f build will have a smaller battery and be kick only. I haven't quite narrowed it all the way down.
Do not use toilet bowl cleaner or anything else that has sulfuric acid. It eats steel. Metal rescue or my preferred rust treatment, which is Phosphoric Acid.
A lot of radiator shops won't mess with tanks anymore. Depends on locale.
