My 1975 CB400F restoration project

[ozzybud]

Hi all i am going to start this thread documenting my recently acquired CB400F Restoration project.
I picked up this bike a couple months ago locally in Seattle for a Very good price. It has just over 20K miles on the clock. It had lots of corrosion and wear that you would expect from a 49 year old bike.

I was able to ride it over the last couple months to make sure it runs good and does not smoke. great compression and pulls very strong. Didn't know it was a six speed until my second ride. also nothing sounds like these small SOHC 4's.

I have been collection new parts,pieces and fasteners  from EBAY, CMS.NL and  David Silver Spares. I love to restore back to Factory Original as possible

 here are a couple pics before and in progress

[ozzybud]

This was my first accomplishment last week. cleaned , restored and re-faced the gauges

[Johnwebley]

Well done

Looking forward to many more posts and pictures

Sent from my SM-A546E using Tapatalk

[ozzybud]

I started in on the front rim restoration this weekend. I have a new DID rim and Spokes from CMS.

I always start with the the rubber still on and clean up the disk by spinning the tire and using 220 grit on a sanding block until all the black marks and glazing is removed. I hold the axle up with 2 boards bolted  to the bench sticking out about 18". I don't have a lathe to face them off so this is the next best method for me to make them look like new.

The Bearing were howling when i was cleaning up the Disk.  The Spanner nut has 2peen marks that need to be drilled out ever so slightly , after drilling out the peen marks, I then heated the hub up with a heat gun. Nut came out with ease and both bearings tapped out with ease. I ordered new bearings and a seal. they should be here by tomorrow.

I use aircraft stripper to remove all the factory clear coat from the hub. the pictures i posted are post clear removal only. I will sand with 400/800/1500 before polishing.

I will sand and polish the hub tomorrow after i install the bearings,i'm hoping with using heat they will drop right in.

I will then clear coat the  hub. i always use catalyzed automotive clear. just 1 coat so it will protect and not chip off.

[AshimotoK0]

Nice work. Which clear coat do you use on your  alloy parts ?... I use MIPA CA . DTM (Direct To Metal) 2k

[McCabe-Thiele (Ted)]

I will sand and polish the hub tomorrow after i install the bearings,i'm hoping with using heat they will drop right in.

As you will know the bearings are a press fit, I found putting the new bearing inside a small zip lock bag then into the freezer overnight that they would drift in quite easily.

A member here put me onto an inexepensive drift tool set that comes in handy for gearbox bearings as well. I'm afraid of heating up alluminium plus my hubs were powder coated so did not want to risk the finish.

.https://www.amazon.co.uk/Professional-Piece-Bearing-Driver-Metric/dp/B00G6KHULU/ref=sr_1_8?crid=UFKYELM2PSY8&keywords=alloy+bearing+removal+drift+set&qid=1705316495&sprefix=alloybearing+removal+drift+set%2Caps%2C70&sr=8-8

[ozzybud]

Yes they are a press fit. But thermal expansion and contraction is your best friend when it comes to installation. Freezing the bearings and heating the structure will make everything a lot easier. .
Using a heat gun should not affect and finish you might have. Unless it spray can paint.

[Laverda Dave]

That's a very nice starting point, it's all there for starters!
Nice work with the gauges as well 👍.
My rat bike project has about 45k on it and unfortunately everything inside the engine appears to be worn out although the wear may in some part be put down to the PO using a sand blaster on the complete engine prior to spraying it black. I'm sure some of the sand got into the engine.
Looking forward to the rebuild posts👍

[ozzybud]

Nice work. Which clear coat do you use on your  alloy parts ?... I use MIPA CA . DTM (Direct To Metal) 2k

This is the Clear I use. It is made by PPG but less than half the price. Sprays,Smells flows out just like the PPG 2K Clear. It seems a lot softer. polishes out nice but on dark colors it gets scuffy faster.Not sure the Manufacturer will Guarantee DTM use. I have used it for years on side covers without failure or yellowing. I have used it on Wood as well. Also I have sprayed it over any kind of poof can(including the Honda Silver Cloud color) and i have never experienced lifting.

I will use this clear coat when i paint the tank and side covers. The good stuff is so expensive and the clear will last a long time but the Hardener has a short shelf life after opening. so i will end up tossing out a couple hundred dollars.

[ozzybud]

A little update on my progress. I got the front wheel re-laced and trued. Detailing the parts and pieces as I go. Using as many new Honda Fasteners and Parts  as possible. Replaced the seals in the front forks and polished up. I have a really nice uncracked headlight bucket that i need to paint and then i will be complete with the front clip. I bought 2 NOS headlight rings for the CB360 a couple years ago. Nice to find out its the correct part for the CB400F as well.

[Oddjob]

Why Honda thought it was a good idea to paint the upper but not the lower crankcase is beyond me, looks awful imo. Didn’t do it on the 750 or 500/550 models, not even sure they did it on the 350.

[McCabe-Thiele (Ted)]

I know it's not original on these Honda Models but I do like black engines always thought they would keep cool better in black.

[Laverda Dave]

I know it's not original on these Honda Models but I do like black engines always thought they would keep cool better in black.
[/quote


Excellent job going on there. I agree with Ken though, why did Honda leave the lower crankcase bare, just crazy. I've decided to get my cases fully painted for practical reasons.

I wish I could travel back in time time Ted and meet up again with the guy who was busy with his sand gun blasting my mates 400 engine before painting it black. 'You'll damage the internal parts of the engine using a sand gun and not covering the ports' I said. I thought to myself how I would pity the poor sap who would buy that bike at a later date and suffer the carnage caused by the stray sand within. How I laughed when 42 years later I bought that very same bike and guess what was inside it . I dont think there is much left of the original innards, complete gearshafts, big ends, mains, valves, guides, chains, tensioner, pistons, rings, clutch, cush drive all binned so far. Mostly as a result of the engine being painted black! I've got say a big thank you to you though Ted for having the complete gearshafts and the NOS Honda piston kit

[ozzybud]

I absolutely agree about the blasting. I only media blast parts/pieces that am 100% sure i can get all the media out.It would not be wise to blast the case halves there are too many nooks and crannies for media to hide.

[ozzybud]

Why Honda thought it was a good idea to paint the upper but not the lower crankcase is beyond me, looks awful imo. Didn’t do it on the 750 or 500/550 models, not even sure they did it on the 350.

On some earlier Honda models Both case halves were left bare aluminum. This is true on my 1200 mile unrestored 1973 CL200. since the finish does not affect operation , Might be as the 70's progressed the customers were more concerned with aesthetics?
My passion is to restore bikes as close to the way the factory produced it. Beauty is in the eye of the beholder. It might not look Pretty but it looks correct! And that is what i am aiming towards