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Hi all - CB450 project bike inside

47106 Views 275 Replies 54 Participants Last post by  borzwazie
Hey all, just checking in. Today is my birthday, so I conned the wife into spending some cash:

Only $50 bucks! Got a title and everything.

As you can see, the fork seals don't exist anymore, and the bike is very grimy with green and rusty corrosion in lots of places. The motor does turn over though. It's got a CB500 motor in it, apparently the guy that owned it before wedged it in.

That's the original tank sitting there on the floor, but I'm told it leaks, and it's crusty inside, so it may not be worth saving.

The mufflers you see on the floor are off some Harleys and the guy had his own CB with these on it, I've got em so I can pass inspection after I get it running, as the originals are cracked in a bunch of places and kind of rusty.

Heck, I even got the key, bonus!

If you follow this (\11\23\bikepics-472165-full.jpg ) you'll see pretty much what I'd like to do to it.

Happy birthday to me!
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Thanks for the replies - and thanks for the link to Glass from the Past, that's a good site.
Thanks for the suggestions! You guys obviously knew what questions were coming, didn't you? :)

I didn't much chance to look it over this weekend, but I did pull off some of the completely dry-rotted fork covers, and found no pitting underneath. There may be pitting up higher, but not where it really counts, so got lucky there.

The spokes are a write-off, and I'll have to lace new ones on. They're pretty pitted. The rims are a little crusty, but I bet I can buff them out, no problem.

I took a look under the seat, the wiring didn't look too bad, and I didn't find any mice nests.

I also hosed down a lot of the bolts with Liquid Wrench to let them soak for a while.

Thanks for the suggestions about the oil in the cylinders. Marvel Mystery Oil is pretty easy to find here, so I'll get some of that tonight.

Rosko, I'd be interested in the tank, you can email me at yahoo, same user name.

Were there a lot of differences between the CB450 and CB500/550 regarding engine internals? They're both DOHC and they look exactly the same from the outside. I better get a manual for both, I guess.

Do you guys recommend that I tear the motor down completely? How hard is this motor to disassemble? Am I gonna need a press to split the case?
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excellent, only 1 manual to read! thanks for the many links.

To buy:

MM Oil
Engine oil
Spark Plugs

Edited by - borzwazie on Dec 18 2006 2:50:37 PM
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You know, something I didn't even think about at first - do I need lead additive for this bike? Or did Hondas of this era already have hardened valve seats? I ask because my dad has a '74 BMW R65 that didn't, and he had to have those seats added.
MM Oil - check.
1 Gallon carb cleaner (I always knew I was glad I had an ultrasonic cleaner!) - check.
Honda Manual - check. (had to order from local honda shop)
extra toothbrushes - check. I hate to use my own, they clean so good but taste so funny afterward.

In addition to the liberal hosing down with Liquid Wrench, today I popped the plugs off and squirted some MM oil down there, gonna let it set a while.

Obviously I won't get much done on it this particular weekend, but my plan for the following week is to drop the carbs and pick them apart. By then my manual will have come in and I'll have a better idea of what the heck I'm doing.

Just to stay motivated, I figure I'll toss up pics of the bike as I go along and you guys can nag me if I get lazy.
So, I'm real disappointed - you guys didn't nag me like I asked and here I am working on it today only for the second time!

Christmas kept me busy, as did the news that I'm going to have a baby girl. Apparently, the only paint jobs my wife can see in the future are painting my son's room pink and moving him to a new room.

Off comes the seat:

And what a seat it is!:

Minus the tank (and camera stupidly in macro mode):

I'm afraid to look inside:

Probably looks like these side covers inside:

One sooty and one sooty and oily plug:

Lots of work to do! Judging from the right cylinder plug, I have a re-ring job in the future. It's hella hard to kick over, though, so maybe compression is ok. The MM oil did it's thing, and the motor moves pretty smoothly with the plugs out.

No battery, which is good! No acid damage. Wiring looks surprisingly good.

Got the official Honda manual. It was print-on-demand, which means "take 4 weeks to ship it to me."

Out of time for today, but clearly I gotta get moving if I want to beat an end-of-May/start-of-June deadline (newborns take more time than teardowns, that's for sure).
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The bike shouldn't be that hard to crank over. Checked the valves?
I suspect the quantities of MM oil, but how best to check the valves?
Also to buy: fuel tubing.

When I was taking the tank off, the little fuel tube that goes between the two sides of the tank was pi**ing fuel all over my garage floor through a dozen tiny holes every time I tilted the tank. I simply cut the other lines. I can't believe it was holding fuel at all.

I'm debating leaving the side covers off. I was thinking about pulling off the current airbox and putting those little individual filters on, but I'm concerned about getting caught in the rain with those things on. Anyone have any thoughts on that?

The center stand is definitely going to go, as are the stock signals and fenders. Fiberglass!

Will these run without a battery?
450 twins are just cool ,even stock I like them alot and they are getting harder to find .I like the bigger tank I put on mine its from a cx500
The front and rear mounts work from a CX tank? No fabbing or welding? I do like the look of that tank better. I have a spare tank that I can mess around with too. I like the look of knee cutouts.

Someday when I'm rich and can afford the parts I'd like to do a replica CR racer. Square tanks are HOT.

I borrowed a battery from my buddy's bike, so I hope to fire it up this weekend. Going to pick up some plugs and fuel line on the way home tonight.

I really appreciate all the advice and comments here! keep 'em coming!
Man, I love the Honda factory manual.

I was reading about the battery and whether the bike would run on a dead or missing battery:

"the battery often becomes completely discharged due to carelessness"

Sorry mom!
So, the weather is warming up, and that means I can work in my unheated garage again. Back to the CB! Yeah, I know, long time, real men don't need heaters, whatever!

Today's first pic demonstrates a set of carbs - one before an entire bottle of carb cleaner, one after:

The carbs weren't too bad inside at all. No jellied gas, and just a little bit of crud.

Our second pic demonstrates that the previous owner apparently couldn't get those carbs to fit in correctly, so he beat them in with a hammer:

So, new intake manifolds...they're both like that. You could see that one carb was pretty black inside, probably from backfiring through the carb or something.

Edited by - borzwazie on Mar 25 2007 6:24:16 PM
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This might sound stupid, but does anyone know where I can get the intake manifold rubber boots? I've been searching online for a while now and can't find them. Note, this is a CB500T motor in my CB450. EBay is a bust, and online, well, I must be blind. I hate to go to the local shop, they're really expensive.
teighlor, I do appreciate it! I'll send you an email.
well, it took a long time, but I finally have a short update. No pics today, tho.

I bought a battery at the local parts store. There are two stores - how did I pick the store, you ask?

First store: I call - "How much for a 12v 12ah bike battery for a cb450?"

"$30 bucks."

Second store "How much for a 12v 12ah bike battery for a cb450?"

"$28 bucks and $51 dollars." "What's the difference?" "Once costs $28 and one costs $51."

First store gets the nod!

I have fork seals and intake manifolds on the way from EBay, so I'll soon be able to fire it up. I put the acid in the battery (first time I ever did that) and charged it for a bit. One question for anyone that knows - when a battery charger meter shows no amperage, that means the battery is charged, right? Shouldn't it take quite a while?

Anyway, I dropped the battery in, turned the key, and thumbed the starter - it turns! Big fat sparks, too. Headlight works, horn works - turn signal indicator works, but the horn beeps when I have the turn signal on, LOL <img src=icon_smile_big.gif border=0 align=middle>

I can't wait to give it gas, I wish my manifolds would show up.
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I'm sooo close to running - I got my ebay'd manifolds in yesterday. They're from a '69 CB450, and the angle is a little different, but the size is the same, and they seem to fit ok.

My wife (pregnant) went into false labor last night, only we didn't know it was false until late this morning, so that has curtailed some of my bike work.

I (very jokingly) suggested to my wife while we were waiting the hours away last night: "Honey, I should have brought the bike - I could be working on it while we're waiting!"

She did not get the joke.

Edited by - borzwazie on May 12 2007 7:25:54 PM
some pics!

new manifolds (well, new to me, they were pulls that I shot some silver paint on the metal):

All the chrome is badly pitted, oh well - the front fender looks ok from 4 feet away or so (I used some metal polish to get the green off):

I took a very quick pass at the sidecover, which had all this funky white corrosion on it, it may clean up ok, no real pitting:

I'm not getting too far into cleanup until I hear it running. I ran out of time, so I'm hoping to start it up this week sometime.

Out of curiousity, a question: The oil in this thing is as old as the corrosion. Should I start it up to warm the old oil before changing, or should I change it before I ever start it?
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I got the 9-year-old gas out of the tank today, put on new fuel line,
cleaned the air filters, dropped the battery in, hit the starter
button, and....


It started on the first try! Honda made a hell of a motor there, it
hasn't run in 8 years, and it just fired right up. It smoked a bit at
first (the choke and the Marvel Mystery oil, probably), backfired a couple of times, then ran like a champ.

I'm so pumped - I've wanted a motorcycle for so long, and to hear it
running really felt great.

Now the real work begins!

Edited by - borzwazie on May 14 2007 12:45:35 AM
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Hey LilBull - I really like the look of the CX tank, did you say that my stock petcock will work?

EDIT: Nevermind, I see where you said it does.

Edited by - borzwazie on May 14 2007 10:32:04 PM
well, I got a ebay'd tank - there's some flash rust in it that I'll need to clean. Didn't I see people here say that muriatic acid would clean this out?
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