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Hi all - CB450 project bike inside

47171 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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Congratulations on your new baby. In the interests of science you could paint your boy's room pink and leave him in there. See if all this "gender role imprinting" mumbo jumbo has any truth to it....just a thought. Its fun to mess with kids' heads.

The bike shouldn't be that hard to crank over. Checked the valves?

Honda go sideways!
quote:Its fun to mess with kids' heads.
Not so much. They pay you back when you're old.
I wouldn't jump to the "ring job" conclusion based on the way those plugs look. The one on the right looks like a new plug. Additionally, plug fouling could be a simple mixture issue. If compression is similar (and acceptable) in both cylinders I'd leave the rings alone. Just be sure to change the oil after soaking in Miracle oil or other solvents. You may want to change the oil, kick it over or start it for few minutes and change it again. Those solvent don't lubricate very well. And, more importantly, why is beer at the bottom of your list?
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?
Compression gauge. Check each cylinder against the recommended pressure and against each other. They should be fairly close to each other (better than 10% I would think). When you get your manual it'll have more precise suggestions. If pressure is not within spec, either the rings, valves, or headgasket might be at fault. If you put your hand over the exhaust port and intake port and feel pressure during the compression cycle you may have suspect 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?
I've removed my side covers and moved the electronics and battery to under the seat and cowling on my 350F. I kept the rubber air box (I don't know if your's has the same) and installed one big far no water problems although I don't ride in the rain often. I read that individual velocity stacks on each carb will require rejetting. Mine will run without a battery but will not start (you have to jump it). That's why I kept the battery. There are total loss systems that will hold enough charge to start it short term but I think they have to be charged periodically. Centerstand is more useful than the sidestand. I'd lose the sidestand but keep the centerstand.

Will these run without a battery?

You're probably better off getting it running as is (with a fresh battery).

Where are you in the process of firing it up right now? Post a step-by-step of what you are doing and maybe one of us can help.

Begin with:

1. Oil topped off.

2. Clean plugs.

3. Fresh (or freshly charged) battery.


1. Pull one plug and re-insert it into the plug wire boot.

2. Turn the ignition on.

3. Hold the plug from #1 next to the engine case and kick it over a couple of times, look for a spark.

3. Check for spark on both sides.

4. If you've got good (read: blue) spark on both sides, great. Worry about timing a little bit later.

Got spark?

Honda go sideways!

Edited by - krapfever on Jan 17 2007 3:19:54 PM
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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 you just have to use the standard 450 or 360 fuel shut off valve and you have to WELD a longer "C" tab on both sides of the front mount,the rear mount needs just a new hole drilled and a rubber grommet from what ever source you want to use. you can see pictures of my bike.the one with dual strips is the fourfifty the single strip is a 360 same tank.I made both seat from the old gas tanks of each bike.

Im so far behind ,that I think Im in first.

Edited by - LiLBull on Jan 19 2007 06:38:21 AM
Do open air box and besure you have no mouse lairs or nuts stored in your air box or a disinigrated air filter to get sucked into the intake.Get to the points and besure they are clean and that they open at least the width of a matchbook cover.See this is ussually the case looking at your plugs (which is not realy not a true way to tell the true condition as they could not be from the bike last time it was started ..who knows put in a fresh set then you have a far more accurate story to read plugs by,but ussually the points close up slowly and the owner reachs to adjust carbs and then you have fouled plugs and the performance is way off its I would set points clean and reset carbs to normal and it should start.)keep the battery and unless your a fabricator of even back yard variety the stock box is fine and even looks cool on those twins .I took mine off and sold them on ebay as i like the look of bareness to the bike.I also relocated the battery box lower on the frame by removing the tool box and welding on some fabricated brackets I also cut and rewelded the brackets for the electric parts that are attached to the box for a cleaner look.I also cut the box down some for more cleaner look.also you can run gas out of any tempory vessel to get it started so dont worry about a fuel tank just yet for the purpose of just hearing her run just be safe about it. I also agree with leting go the kick stand and keeping the center stands .It is a big lump of metal I felt good removing from the frame.It looks cooler on the centerstand in my opinion .And I hope you have a IMPACT screw Driver .It a vintage bikers first tool of deployment.

Im so far behind ,that I think Im in first.
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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!
A big "Hell yeah"" for the impact's save my butt a bunch of times....everything from case screws to brake resevior covers. In fact, if the fastener has never been removed I start with impact screwdriver. That way you minimize the chance of buggering up the head. I recomend everybody have one.
yep, ya gotta get an impact driver.... and a 2 ld hammer....then get a screw kit and get rid of all those shitty phillips heads, or take one of every size that you need o a place that makes metric screws, im in cleveland so theres a million places, and get yerself some good hex heads......
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.
It never ceases to amaze me how people attempt to solve mechanical problems with heavy blunt objects.

You may be well past this by now, but on the subject of 450s and batteries: no, they won't run without a battery, but there's a pretty simple solution. You can get SLA batteries that are easy to hide and will mount in any position - and they're cheap. I'm running a 450/500T hybrid with a 3AH 12v battery (not enough to run an electric starter, but plenty to create the magnetic field necessary to make the alternator work), which is only 1" wide and tucks invisibly underneath my seat where I've mounted the rest of the electrics. I'd post a pic but haven't any goddamned idea how.

Done a compression test yet? I'd be interested to know. If not so good, I find the 450 heads pretty easy to work on. No springs to poke your eyes out. If you do, have a look at the exhaust left rocker. It's the first thing to go (last in the oil path).

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For what it's worth, 450 manifolds are identical.
Hey i gots a cb450 engine layin can have anything you want off of it, as long as ya pay for the shipping....its a 72 K5.....let me know.
teighlor, I do appreciate it! I'll send you an email.
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