Topic: 1972 CB500 hasnt ran in 15 years...

[samIam]

Hey all, new guy with some questions.  I'll start by saying I know nothing about bikes, never rode one and never worked on one.  I am a young-ish mechanic and I've build a few motors but never touched a bike.  I just got this 72 CB500 that hasnt ran in 15 years from someone as a payment for work done, about $300 worth of work.  As soon as I got the bike, I started taking it apart.  The goal is to get it running without spending a lot of money and to not have to open the motor.  Motor spins pretty easy and I took a plug out and saw a decent chamber.  The only valve I could see come down was in decent condition, also. 

My son really likes it, wife told write a will





What I've found so far...rusted tank.  I've got vinegar in it now to soak.


Brake fluid completely dry


Been laid down?  Seems like there would be more damage


Handle bars bent


Got the carbs off and opened them up...


Three of the four bowls looked like this


This one has corrosion inside, can anything be done about it?


Clutch plates move when I pull the lever but only a couple on the outside.  Been told they will free up eventually and the main thing is that they arent froze in place


Points look good, alt looks decent.  Hopefully they work



Here is the gear selector foot lever, the rod that it is attached to has major damage and someone just drilled a hole and did a cotter pin type setup. Works pretty good.  I really dont want to open the motor up to replace it.



The wiring looks ify at best.  Some wires look like they were pulled out of connectors and some arent connected to anything.  I'll have to get some more pics of the wiring because I'm hoping its still good.





Anyway, thanks for letting listening, hope y'all see any easy process to get it running

[fmctm1sw]

I don't own a 500 but... 

carbs:  I've seem far worse.
instrument cluster off a later bike?
Master cylinder and brake caliper frozen?
yeah, looks like some wiring oddities.  Did it have spark?

you have your work cut out for you but I've seen (and owned) worse.  Welcome to the board, easily the best resource for SOHC Honda bikes on the net.

*edit*  You might be able to push that gear selector shaft right through the right side of the case if you take the clutch basket off and undo the shift linage under it.  Something tells me I did that with an old CB175 I had with the same clutch set up.

[mono]

welcome! 

wow the cooling fins on the engine look like they took the brunt of the damage from whatever caused the points cover to get scuffed... yikes.  but as long as there aren't any structural cracks in it, you're probably OK.

-the carbs (which look amazingly clean on the outside!) can be cleaned.  that grossness inside the float bowls is probably from the tank.
- may want to replace the brake lines if everything's crusty, and maybe a master cylinder rebuild.
- the electrical looks like it's been seriously hacked at.  also, the those front turn signals are pretty interesting... 

for the equivalent of $300, i'd have taken it!

[dhall57]

Welcome from North Carolina. The smile on your sons face says it all. Motor spinning freely is a BIG Plus. On the negative side, tanks rusted pretty bad, and looks like one of the PO's did there best to destroy the wiring along with the shifter shaft. Everything else not bad. I've seen and along with everyone else here have seen a lot worse for sure. Like most of these 35 to 40 year old sohc4's just needs some T.L.C. Good luck and keep us informed on your journey to get it back on the road

dhall

[LesterPiglet]

those front turn signals are pretty interesting... 

Normal Honda indicators for that year I think. They are also on 750's and my 550F.

[samIam]

Thanks for the replies.  I'm hoping to get it running by changing the oil, plugs, battery, cleaning the carbs and tank.  Think that will work?  Also, if anybody has any parts I need, let me know.  So far I need handle bars, plugs, carb rebuild kit, tires, driving lessons, liscense, experience and a convinced wife.  lol

[mono]

those front turn signals are pretty interesting... 

Normal Honda indicators for that year I think. They are also on 750's and my 550F.

oh i thought it looked like they were mounted a little far forward.

[vames]

Wiring looks like it's going to be the hardest thing to get back to normal. A word to the wise: don't mickey mouse it back to just for the cheap thrill of getting it running. If there are busted connectors or chunks of wiring, bring it back to stock. You can get replica bulk and bullet connectors for relatively cheap at www.vintageconnections.com. You and future owners of your bike will be very thankful if you don't hack and patch just to get it running.

[bollingball]

those front turn signals are pretty interesting... 

Normal Honda indicators for that year I think. They are also on 750's and my 550F.

oh i thought it looked like they were mounted a little far forward.

They do look a little odd if you look at the 2nd pic. it looks like they should go in that hole closer to the tubes. But I don't have a 500.
Looks like you might have a good helper.

[TwoTired]

those front turn signals are pretty interesting... 

Normal Honda indicators for that year I think. They are also on 750's and my 550F.

oh i thought it looked like they were mounted a little far forward.

They do look a little odd if you look at the 2nd pic. it looks like they should go in that hole closer to the tubes. But I don't have a 500.
Looks like you might have a good helper.

The front blinkers are mounted in the original position.  But, those aren't the original fork cover ears.  Those are probably from a CB550.  The forks were likely replaced after the accident that the bike suffered through.  Front fender is from a 77-78 model.
I'd certainly make some measurements to be certain things up front are straight and the repair work was done correctly.

Bars are bent.  If this was the result of the same accident, it would indicate a non-professional/incompetent repair, done on the cheap.

Clean the tank, (electrolysis would be my method of choice (fuel valve removed).
Clean the fuel valve.
Clean the carbs (don't forget the main emulsion tubes)
I'd get the proper 5.5 mm fuel tubing to replace that nasty "clear" stuff".
Make sure there is oil in it, and it should be ready to start up. 
Put a good battery in it.
Set the point gap and static timing.
If the key switch won't provide power to the coils, then jumper from there to the battery POS terminal and the bike should kick start.

Do front brake overhaul.  (See FAQ)

Address chain and sprocket status.

Tires may be good enough for around the block.  But, I'd not be comfortable above 50 MPH on them.

Sorting the electrics just takes some patience and a wire diagram in the Honda shop manual, which is a must have.

Should be a fun bike, and not very difficult to get road worthy.

Cheers,

[samIam]

Thank you for the insight, never would of thought about stuff being replaced after an accident.  The headlight is not on tight, at moves around when you tap it.  Anybody got some handlebars and a mount for the headlight?  I was looking in the parts for sale section but I'm not sure what years and models I can use parts from.  What type of measurement should I make? 

For the tank, the vinegar has done wonders.
Fuel valve needs gaskets
Can I stick the carbs in carb cleaner complete like pic below?
Clear gas lines are gone now.
Gap and points are new to me, gonna need some help there.
Chain and sprocket "look" good.  How do I tell?
Tires are from 95 and look scary.




I see two nipple between the two middle carbs that had nothing connected, vents?

[Deltarider]

Your carbs are not bad. BTW, no need to separate them (ever).

[dave500]

those are vents,just put some hose on them and route them downwards,the gear shaft can be pulled through from the clutch side once the basket is off,lots of bikes are like that,drop the pan and desludge it aswell.

[fmctm1sw]

Thank you for the insight, never would of thought about stuff being replaced after an accident.  The headlight is not on tight, at moves around when you tap it.  Anybody got some handlebars and a mount for the headlight?  I was looking in the parts for sale section but I'm not sure what years and models I can use parts from.  What type of measurement should I make? 

For the tank, the vinegar has done wonders.
Fuel valve needs gaskets
Can I stick the carbs in carb cleaner complete like pic below?
Clear gas lines are gone now.
Gap and points are new to me, gonna need some help there.
Chain and sprocket "look" good.  How do I tell?
Tires are from 95 and look scary.
I see two nipple between the two middle carbs that had nothing connected, vents?

On the carbs, there are folks that totally disassemble and those who are against it.  Yours don't look bad enough to be totally disassembled in my opinion.  In the 350 carbs at least, there are little felt washer things on the arms of the throttle slides.  I don't know that dipping the whole rack is a good idea.  But again, your carbs don't look bad.  I'd just make sure the passages are clear.  You can measure the chain.  I had a post here with a couple stretched chains and a good one but without the search function, it may be tough to find it.  Those open nipples are an atmospheric pressure source to your bowls.  Typically there are hoses on there that route up toward the airbox.

[TwoTired]

The headlight is not on tight, at moves around when you tap it. 

Probably an assembly error.  There is supposed to be a rubber washer between the headlight shell and "ear mount".
It can be tricky to the get the turn sig. posts tight enough and still be able to adjust the head light position.  Probably why the turn sig posts were mover to another location on subsequent models.

Anybody got some handlebars and a mount for the headlight?  I was looking in the parts for sale section but I'm not sure what years and models I can use parts from.  What type of measurement should I make? 

What is your goal, stock positioning?  Or, low uncomfortable "race" bars? 
What width, rise, and pull measurements do you prefer?

For the tank, the vinegar has done wonders.

Watch out!  Vinegar eats base metal as well as rust.  Can you say pinholes?  Vinegar won't eat through the paint from the inside, but it will metal.

Can I stick the carbs in carb cleaner complete like pic below?

I wouldn't.  You do have the Honda gasket set/kit for them, right?
16010-323-315

Gap and points are new to me, gonna need some help there.

I'm reluctant to type that out yet again.  It's been described in many threads on this forum.  And is in the owners and shop manual.

Chain and sprocket "look" good.  How do I tell?

How far can you pull the chain away from the sprocket mid curve radius?

I see two nipple between the two middle carbs that had nothing connected, vents?

Yes vents, should have 3.5mm tubing routing back and down between engine case and swing arm pivot.

[samIam]

Well I'm glad to hear that y'all think the carbs dont need to be rebuilt.  Wasnt looking foward to that.  I'm just gonna get the gunk out and call it a day.  Everything that I can see inside of them look good.  Anybody got a carb kit?

For the handle bars, the stock ones feel good.  Never really thought of position.  I'm 6' tall, 245lbs...that got anything to do with handlebars.  Just want something thats easy to learn on.  Stock ones feel good, though. 

The vinegar has done a good job and it seems ready to be done.  I'll get it out of there and take a look around.  Also saw a pic of the fuel cutoff valve/petcock(?) and it looks like there is a little tube that goes into the fuel tank, mine doesnt have one, like it broke.  It doesnt leak. 

I'll check around for setting the points.  I'll also check the chain. 

[TwoTired]

Well I'm glad to hear that y'all think the carbs dont need to be rebuilt.  Wasnt looking foward to that.  I'm just gonna get the gunk out and call it a day. 

Do remove the pilot jets and clean them.  Just might be all the "rebuild" you need to do.

Personally, I'd also push out (toward the bottom) the main emulsion tubes that are behind the bottom main jets, to verify they are clean.  The place where you push is in the carb throat where the slide needle pushes in.  Be careful with the needle AND the hole where it pokes in, as that is the needle jet.  Don't want that damaged.

Cheers,

[samIam]

So I think I broke something off the carb.  I was getting the old clear gas lines off when the nipple came off with it.  How do I fix this?


You can see the one on the right, I broke the left one.  Well, I dont know if it broke or is supposed to be able to slide out.  There was gasket/hardner stuff around it came off.  A previous repair or stock setup?


TwoTired, I'm trying to think about where you are telling me to push but cant picture it.  I dont see where I would actually push.  You are talking about the piece in the middle of this pic below, right? 



Almost forgot, I bought a battery for it and the headlights/brakelights work, not the blinkers that I can tell.  electric start turned the motor over nice and healthy.  Got me excited to finish the bike.  Tank is drying, need a carb gasket set, fuel lines, oil change, run through brake system and test ignition system. 

[TwoTired]

So I think I broke something off the carb.  I was getting the old clear gas lines off when the nipple came off with it.  How do I fix this?

Ouch.  That''s gonna be more work.  I went out to checked my spares.
Between the carbs is a T fitting.  The nipple is soldered or brazed into a barrel that fits between the outer carbs.  To do the repair justice, I would remove the outer carb from the connecting plate to get at/remove the barrel.  Then at least use silver solder to mend the T fitting, inserting the nipple back into the barrel.
You'll need 4 orings for the barrel during the refit.  They will be in the 16010-323-315 Honda rebuilt kit.

TwoTired, I'm trying to think about where you are telling me to push but cant picture it.  I dont see where I would actually push.  You are talking about the piece in the middle of this pic below, right? 

On the center post is the main jet in your picture.   It is likely glued in with dried gas along with the oring that seals jet to carb body.  Don't expect to reuse that oring.  With pliers, pull that straight out and you can see the flat end of the tube to move next.  Now look in to the carb throat and open the slides as far as you can.  You will see a needle extending from the slide and a brass nub that the needle fits into.  That brass nub is the other end of the tube you saw under the main jet, and what you have to push on to get that emulsion tube out of the carb body.  Review my notes in prior posts about avoiding damage to it.

Do get yourself some aerosol carb cleaner and clean as much crud as you can from the bowls and the parts that reside in the bowls.  Also, scrape off that corrosion so it can't flake off later and plug that tiny .016 inch pilot jet orifice.

Have you checked the float for free swinging and the smooth float valve movement?  Do the float valve needle spring pins move freely?  If not, bathe them in carb cleaner.

Cheers,

[samIam]

I tried taking a carb off once already and couldnt get it off.  I took the two main screws off the plate that connects them but couldnt see what else needed to be done to get it off.  I was thinking I could push the nipple back in and use JBWeld to hold it there. 

[Deltarider]

Yech, they look dirty, still no reason to separate carbs.

[samIam]

Well I have to take one off the rack because I broke the fuel inlet T-fitting.  I did see the procedure in the manual, I'll try it.

[fmctm1sw]

Well I have to take one off the rack because I broke the fuel inlet T-fitting.  I did see the procedure in the manual, I'll try it.

If you remove all 8 of those phillips screws the 4 carbs will come off of that backing plate as a unit.  To separate the carbs, you will need to unscrew those bronze looking (after you clean them) hex nuts near the very top.  Under those hex nuts are some very small pieces that need to come out to separate the carbs.  The tubes TT mentioned are under (or above, whichever way you look at it) the main jets.  Sometimes you can take the main jet out and pull them out (or they fall out) from the bottom.  I've used a Q tip to snag some of them.  You probably won't be so lucky though.  The throttle slides will need to come out in order for you to tap on them from the top.  I'm not sure of your level of ability but splitting a carb rack may be a bit aggressive if you've never done it.  Also, once you pull one off, the o rings on those little barrel connectors may start to leak, mine did.  Take a lot of pictures.  Maybe do a search for some other carb threads.  I know I have a couple that show my carbs in various states of disrepair.

[samIam]

I got them apart, wasnt too bad.  I'm gonna get the emulsion tube out so hopefully they come out from the bottom. 

[fmctm1sw]

Good deal...