Topic: 1975 CB400F -> Project "something fun to build and ride"

[gsnorcal]

And while taking a measurement on the carbs, one of the boots separated. So, I'll be ordering 4 new ones, which it seems are still available.

Have a nice evening,
Dave

I'll make you a deal on a brand new set from Honda. I ordered them and could not get my old ones off without destroying the screws. I have the boots and the "O" rings that go behind them. PM me if you are interested.

Doh! Mine are already in the post from England/DSS. Thanks for the offer.

BTW, I had to use an impact driver to get my screws out.

[gsnorcal]

Anyone got a photo of the CB400F battery (-) to frame/motor connection? I can't remember how this was made originally. I thought I had a photo, but I don't.

Thanks,
Dave

Nevermind. I found a pic that I took before taking it apart. Lower right corner of this pic, at the motor mount.

[gsnorcal]

After a two week wait for the frame to be powdercoated, the project resumes. Today I got the frame back, in satin black powder. Once I got it home and removed all the masking from the frame and swingarm, I proceeded to install new shock bushings and new bronze swingarm bushings. Swingarm is installed on the frame. I also pressed in the steering races "for real".

The highlight of the day was receiving the most extravagant item of this entire build in the mail. TTR400 billet rearsets!!! I'll take pictures once they are on the bike, but they are just like this, black and all:



I would have machined these myself, but there are a lot of details to get the linkage as nice as this kit. Sure, the pegs, brackets, and levers would have been pretty easy to make. However, I'm feeling in a rush to get this bike back on the road.

I hope to start making really rapid daily progress from here on out. I'll be sure to take a bunch of pics.

Dave

PS-I've started machining another "R6 wheel conversion kit" for a fellow member. If anyone needs any machining done, let me know. I'm in a shared shop space now, with CNC capability. I can make just about anything you need.

[Greggo]

Those rear sets look great!

[Aladinsane07]

Awesome project.  I'm a big fan of where this is going.

[gsnorcal]

It's been a long time since these old friends spent any time together!



Anyone remember what goes in between the frame and left rear upper motor mount? I have the parts manual but I don't see it. A bushing or roller for the chain? It's about a half inch gap.



Dave

[-CB-Jamie-]

Ya theres just a metal bushing/spacer/collar whatever you wanna call it that goes in there,

It's no.14 in the following
http://www.cmsnl.com/honda-cb400f1977-usa_model7214/partslist/F++21.html

Can't wait to see this going back together, you get a great sense of achievement once you start to put things back together and it starts to look better and better as parts go back.

Jamie

[gsnorcal]

Thanks Jamie. I found the missing piece.

Here's a pic of the old girl standing on her own two feet!



Dave

[FunJimmy]

Dave

It looks like the forks are slipped up in the triples quite a bit.
Are 400 forks that much shorter than the R6 forks?

[gsnorcal]

Dave

It looks like the forks are slipped up in the triples quite a bit.
Are 400 forks that much shorter than the R6 forks?

Yea, I was surprised as well. I recorded 26.4 degrees of rake on the stock bike before dis-assembly. These are close to that number. I'll measure the stock rake from a local 400 when I get a chance.

Another reason they look worse in this photo, as compared to earlier ones, is because I have decided to put my clip-ons below the top triple. With the rearsets, it's more comfortable lower.

Dave

[cwchan]

Great build.  I'll take the original foot controls pegs off your hands if you're going to sell them

[Syscrush]

Another reason they look worse in this photo, as compared to earlier ones, is because I have decided to put my clip-ons below the top triple. With the rearsets, it's more comfortable lower.

It also looks 10x cooler.

[gsnorcal]

Dave

It looks like the forks are slipped up in the triples quite a bit.
Are 400 forks that much shorter than the R6 forks?

OK, here's what I have observed about the forks. I recorded the rake on the stock bike at 26.4 degrees under it's own weight, bike vertical (no side/center stand). The photo you see above is 26.3 degrees. I would still like to confirm this myself, on a local bike so that I understand how it was measured.

However, I measured the stock front-end last night. 20.5" vertically from the center of the axle to the height of the lower bearing race. In the position above, where the rake is 26.3, when I uncompress the forks, the current length is only 19.5" from axle to bearing race.

This makes some sense, since the spring rates are different in the forks. Basically, the stock suspension must sag more under the bikes weight to provide the same rake.

In the end, I think what this means is that I need to ride the bike and get a sense for the handling, and commence fine-tuning.

Dave

[gsnorcal]

Today was a milestone. I buttoned up the motor this early this morning--installed new clutch, adjusted valves, mounted stator. Then my buddy Chris (goatee) came over to lend a hand. We decided that it would be fun to get the motor running. In the time since I reassembled the carbs, my new jets arrived. So, we decided to bump up from 80 to 90 mains for the first fire up. So, we put those in and mounted the carbs. Then we temporarily rigged up the battery to the starter and coils, with a simple inline switch for the coils. No harness yet, since I am building one from scratch. We turned the motor on the starter for a few cycles until I observed oil flowing up at the tappets.

Then we connected the coils...

CB466F First Start

It started right up. Granted, it was only running on 1-4, but within a few minutes, we found a faulty connection at the points and 2-3 came to life.

I also connected and bled the front brake. Jimmy, that 11mm passes my garage test. Probably still has a little air in it anyway.

I connected the clutch cable and the throttle cables. All the (brand new) cables are too long for the new clip-ons. Expect them to appear in the flea market soon.

That's all for tonight.

Dave

[gsnorcal]

I got the wire and connectors that I need to make a new harness from Z1. More expensive than I had hoped, but it's nice to have most of the original colors. While my wiring will be a little different than stock, where I can, I'd like the old and new colors to be assigned to the same circuit.



And, for the last week I've been shaping my seat and cowl. I'm getting very close to finishing. The different color markers tell me when I've sanded down that far. Seems to help. The shape is based off the lines of the tank.





My friend is the owner of Renazco Racing, makers of the best dual sport and off-road rally seats. He's gonna help me make some cool pads for this seat. Check out his seats at http://www.renazco.com.

I also repainted the original Lockhart oil cooler today. I sandblasted it last week.

And finally, here's a picture of that carbon fiber battery tray. It hangs between the seat rails and you can see about an inch of it below the rails. So, the carbon looks good there. I'm no master of composites, but this is strong and doesn't look horrible (well... at least you really can't see much of it) 



My birthday is Saturday, so I really hope to get enough of the wiring done to at least ride the bike around the block. 

Cheers,
Dave

[FunJimmy]

Dave

Great progress man.
It's so nice when you hear the bike fire for the first time, isn't it?

Glad the 11mm passes the garage test, now go ride the hood and let me know if it passes the street test.

Cheers.

[gsnorcal]

First ride!!!

Cb first ride

First ride

The bike runs great. I only rode it up an down my dead end street a few times, as the charging system and lights are not yet wired (I'm waiting on a few pieces of hardware in the mail). She runs better than ever. The 90 mains seem to be in the right ballpark with the big bore/pods/exhaust. The clutch needs a little adjustment--it slips a little when the revs are up. The front brake is great! Jimmy, the 11mm feels pretty good. My rear brake is way out of adjustment--maybe needs rear shoes.

Tomorrow I am bringing the bike over to Renazco Racing. James is gonna help me make my own seat pads. With some luck, my wiring hardware will arrive as well, and I can connect up the charging system and some lights.

Dave

[greenjeans]

Nothing I like better than stumbling on a build I haven't read through before.

Great work.  You're right, that is going to be very fun to ride.   

You leaving the flame paint job ? 

[gsnorcal]

About the flames... Long-term, I'm sure I'll be painting over them (or buying one of DSS' repro tanks to paint). The paint job on this tank is really shot. You should see it in person. However, the PO is sentimental about the bike, especially the flames, so I wanted him to see my redo with that tank still on it. I will say that it is pretty "fun" to have the flames.

By the way, the seat is not painted--that's just primer and a guide coat. Still have some glazing and more sanding to do before paint. It will be rattle-can black for the time being, until I decide what to do about the tank.

I can't believe how well the bike is running considering that I haven't touched any of the fine controls--timing, carb sync, points gap, etc. I even removed the points plate as part of the rebuild and just slapped it back on.

Dave

[Syscrush]

The flames are among the best parts of that bike.  Do you know when they were done?

[socalenduro]

The flames are among the best parts of that bike.  Do you know when they were done?

+1
and the fact that they are faded makes it even better...
i say try putting a semi gloss clear coat over it so it doesnt fade more and have a perminent used look.

I wish i had done this with my stock tank. I look back at pics and kinda miss the sunfaded and gas eaten paint....

[TPColgett]

The flames are among the best parts of that bike.  Do you know when they were done?

+1
and the fact that they are faded makes it even better...
i say try putting a semi gloss clear coat over it so it doesnt fade more and have a perminent used look.

I wish i had done this with my stock tank. I look back at pics and kinda miss the sunfaded and gas eaten paint....

+2!

After getting my tank back from the radiator shop, I miss that well loved patina the original decals and paint had! I get nostalgic whenever I think about the history and character of these bikes and that would be a neat way to preserve some of it..

[gsnorcal]

The flames are among the best parts of that bike.  Do you know when they were done?

Tank was done in '76 or '77. Been there as long as the PO can remember.

Thanks for the "votes"... Duly noted. I'm still not sure where I am headed on the paint. We'll keep thinking...

In other news, I got the charging system wired up this afternoon. That seems to be working fine. And I got the rear lights wired. Just need to finish the forward lighting, speedo, etc.

And, this morning's time was well spent. My buddy had me up to his shop and we (99.999% he) made my seat pads.



Lots of fabric and foam choices. The rear pad is 1/2" of firm foam. The seat is 1/2" of medium memory foam over 1/2" of firm memory foam. For fabric, he has all colors, in suede, leather, and vinyl. I wanted black since I don't know where I am going with paint. I thought about leather, but I didn't care for the pronounced "organic" texture of what he had on my "resto-MOD" sorta racy build. So I was thinking plain black vinyl, but it was too plain. So, I ended up with a rather subdued carbon fiber black. It has a nice texture, geometric and modern, and doesn't come off as cheesy as some fake carbon. I'm really liking it. It's not attached to the seat pan yet--I still have sanding and painting to do on that piece.

More tomorrow.

Dave

[Syscrush]

Tank was done in '76 or '77. Been there as long as the PO can remember.

Love it.

And, this morning's time was well spent. My buddy had me up to his shop and we (99.999% he) made my seat pads.

So, I ended up with a rather subdued carbon fiber black. It has a nice texture, geometric and modern, and doesn't come off as cheesy as some fake carbon. I'm really liking it. It's not attached to the seat pan yet--I still have sanding and painting to do on that piece.

Very nice!

More tomorrow.

Can't wait!

[gsnorcal]

Today's update has some good news and some bad...

Good news first:

I finished up the wiring and went for a nice ride. I started with visiting my two local moto shops just a few miles from home. That way, if anything came up, we could fix it. Bike ran great. Front brake is awesome. Very very fun to ride. After the shops, I took the back roads to a friends house about 10 miles away. It is absolutely everything I had hoped for in the build.



Bad news:

The engine paint, which was by far the most annoying part of this build, is already irrecoverably ruined. The silver paint and/or the clear coat (both of which was previously cured in my oven, per the can's instructions, has turned to gold/brown across the whole top end of the motor. The stator cover still looks good, as does the oil pan and filter cover. But even half of the tranny/bottom end has turned.





I'm super disappointed because there is no "good" remedy. Notice no bluing on the pipes, and I've got 90 mains, so it's not dangerously lean.

Naturally, I am wondering if the bike somehow got too hot. I measured some temps within about 5 minutes of shutting down the bike. Prior to shutdown I had ridden about 10 minutes at moderate speed, not in traffic. The cylinders were showing 120C (246F). The oil itself was about 110C. I did notice a small amount of steam coming from the breather hose when I was at stop signs. Normal? Also, when I checked the oil temp after riding, there was a little mist down inside the filler.

Question is, how hot should one of these motors get? Surely not 550F degrees, like the paint is advertised for! But also, in general, for the motors safety, what kind of temps should I be seeing?

I do not have my oil pressure light wired in yet. However, I did watch and see oil pumping up into the tappet covers when I first started her up. So there is oil circulating.

Gotta admit, the bad news is outweighing the good after the first real ride. Mechanical glitches cause me no great discomfort, but this is a real suck.

ARG!!!