Topic: 1980 Honda CB650: The Cash Machine - major progress

[JimJamerino]

The acquisition of my Honda CB650s is a story in and of itself, told here, but essentially I have two non-running 1980 CB650s for $150. One is a Standard, the other a Custom, both 1980 American models.  The Standard was a project started years ago with my friend Bob, while the Custom came into my ownership from a Craigslist "parts bike" ad.  Needless to say, the "parts bike" was in more complete and usable condition than my Standard, so the Custom is underway as a daily rider, and the Standard will eventually become a chopper or bobber project.

Neither one has run in at least 10 years.  What's odd is that the parts that were no good on the Custom are new or very solid on the Standard, so hopefully I'll be able to cobble together a solid runner.

Pic goodness!!

The Standard... sort of.


A closer view of the Standard's frame and some of the guts.




Original M/C on Standard


Molten spark units.  I understand Hondaman can help a brother out here...


Standard gauge cluster.  A bit over 10,000 miles on this one, and I have no reason to believe it's not accurate.  When I go to chop the Standard up, I am TOTALLY doing Industrial Cafe's LED mod... and probably some custom gauge faces.


Put the headlight back on and reconnected as much of the wiring as I could figure out.


This is the inside of the Standard's tank.  I think it may be beyond repair.


The Standard's engine.  Pretty greasy, pretty neglected.


The oil filter bolt is boogered to no end.  Don't know how I'm supposed to get it out now.


Exhaust ports


The seat.  Not bad.


Boogered up exhaust from the Standard.


Carb rack.  Piston style, moves fairly freely.  Definitely needs to be dismantled and thoroughly cleaned.  Probably a rebuild kit is in order, too.






Next post: the Custom.  If you have questions or comments about certain parts, I may have pics of them.  Any advice or feedback is appreciated.

[JimJamerino]

While reassembling the Standard, I picked up a non-running CB650 Custom for $150.  I think I will have better luck getting this one to run than the Standard.

The Custom.


This is just kind of a cool picture.


A lot of original decals still in pretty good condition.


Original 4-4 exhaust looks pretty good.


It must have been dropped at some point.  The left exhaust has a little damage, and the clutch lever was all sorts of ganked up.


Insulation on the spark units is melted on this one too.  Sooner or later, I'll be yelling, "Oh, Hondamaaaaaan!!"


The engine and carbs with the tank off.


This is what really sold the bike.


5500 miles on it before it was parked 13 years ago, according to PO.  Missing the choke cable... and I have a new one that was purchased years ago for the Standard.  Installed, it feels like it's moving the butterflies.


Missing the headlight assembly.  After putting the connectors together, it turns over strongly.  I swapped the headlight assembly over from the Standard, and it lights up fine.  The PO said there was a fairing on it at one point, hence the snarly, yet loose wiring.


A stock Custom handlebar is more of a buckhorn style, and these are definitely not buckhorns.  The bars had to have been swapped out at some point.  I'll point out the issues involving the M/C a little later.  The return throttle cable was jammed up big time... and I had a brand new one bought for the Standard.  Swapped out, life is good!


I swapped out the bars from the Standard onto the Custom.  In the process, I also put a Standard M/C on it.  Looks pretty all right, I think.


The top one is a Standard M/C, the bottom from a Custom.  The angle of the reservoir reflects the tilt from the buckhorn bars.  Also, the Custom M/C doesn't have a banjo bolt; the brake line has a flange that runs straight into the cylinder.


I don't know where these bars are from, but the hole for the stud on the controls is too far toward the front of the bars, causing the controls.  Ultimately the M/C and brake lever are rotated much too far out of spec to be useful.


Headlight reinstalled on the Custom.  I think the headlight ears aren't right, because the turn signal stalks are flat and there's a hole that looks like it's supposed to go to on the fork clamp tube, but doesn't fit at all.


Starting to look like a motorcycle again.


Tomorrow... CLR in the tank, followed by alcohol to pull the water, followed by a gas fill to inhibit rust.  Hook it up and see if it runs!

[Frankenkit]

hi there!  just lookin' in as a fellow 650 fan.    
The oil filter bolt thing is pretty common.  The flat washeresque base of the bolt's head is steel and the filter cover is aluminum- they tend to weld themselves together.  If you carefully take a grinder to the bolt head, you should be able to grind through it and get the filter cover off.  You'll need to be extremely careful not to mar the surface, though, or you may get an oil leak there.  Most find the remaining shaft of the filter bolt spins right out after that, however.

Hondaman does electronic ignitions on the other SOHC4s but I'm not sure about your melted ignitors.  There ARE different models that use the same ignitors, though, so they're not terribly hard to find used.  

You'll want to pay particular attention to the idle circuit on these carbs- the 650s were leaned out real, real hard from stock, and unless your idle circuit is pristine, you'll have some issues idling.  I'd also recommend fully unracking the carbs and checking the air cutoff diaphragms for pinhole leaks, as well as your accelerator pump on #2.  

Good luck! I look forward to seeing your progress!

[Hush]

Everything Kit said and then some.
Looks like a fun project, the custom has the best rake of all the 650's in my opinion.

[JimJamerino]

Today's project was to clean the tank and see whether or not the Custom runs.  Long story short, yes, it does!

The tanks for the Standard (black) and the Custom (gray).  I'll used the totally crapped out petcock from the Standard to block up the Custom's tank for cleaning.


This is a dead petcock!  It is no more!  It has drawn down the curtain and joined the choir invisible!


I'll not be reusing this one, but it does work.  It's from the Custom, and it'll be good to have a spare.


Old and new.


My cleaning materials:
28 oz. bottle of CLR
Boiling water (approximately same amount as CLR)
BBs
Small nuts
A bucket

Procedure:
1. Empty gas tank as much as possible.  Put on CD.
2. Pull petcock and plug tank (I used a completely blocked old petcock)
3. Pour in CLR, add boiling water.
4. Add BBs and nuts.
5. Cap the tank and start sloshing and shaking the tank.  Check progress every song or two (4-8 minutes).  Be sure to use a flashlight to see as much as possible.  I thought it was going well until I tipped the tank to see the bottom, and saw there were a couple of spots of rust still hanging on. 
6. Once the tank looks good, drain cleaning solution.  Rinse with gas.
7. Fish out the BBs and nuts with a magnet.  This took as long as, if not longer than the sloshing phase.
8. Install tank on bike, fill to the brim with gas.

Before.


After.


The cleaning solution to be discarded.


I picked up this cleaning procedure from www.hondacb650.com.  If you have any suggestions or comments, please let me know.

So, after all this cleaning, I was feeling pretty good about things.  I put the tank back on the bike, hooked it up, and filled it to the brim with gas.  My neighbor and his kid were present for the momentous occasion... to momentarily step in front of the camera, fortunately not at critical moments.  Bear in mind, this engine has not been run since 1997.

It started right up, but what made me stop was the gas flowing out of the #4 carb overflow like it was a direct line to BP.  I know it's a good idea to clean the carbs right away, but I just wanted to know if it would start.

Next step, yank the carbs and go to town with Simple Green and carb cleaner.

[Frankenkit]

I actually really dig brakekleen (or whatever brake cleaning spray you happen to get) because it seems kinder to your rubber bits than carb cleaner.

Congrats on getting her to start!!!!!

[The_Crippler]

Creative way to clean the tank...might have to give it a try.

[scunny]

instead of bb's I use a length of chain. does the same job but easier to fish out.

[The_Crippler]

instead of bb's I use a length of chain. does the same job but easier to fish out.

In my case, I don't have a spare hunk o' chain...but I do have a box of BBs...

[JimJamerino]

I bet sloshing a chain around inside would be just as effective, might even work better.  I thought I could pull the petcock and have the BBs drain with the fluid, but apparently there's enough of a lip inside to prevent that.  If you do go with the BBs, Crippler, I suggest having a magnet on a stick on hand.  Use one where the magnet doesn't move at all (the one I used had a couple of little joints so it got stuck to the side of the filler neck pretty easily).

[JimJamerino]

I've been trolling the web for a carb gasket kit on my 1980 CB650C.  As seen in the previous post, gas gushes out of the #4 overflow like it's a faucet, and I need to clean the carbs anyways.  I figure as long as I've got the carbs out and apart, I may as well take care of the gaskets, since it sat for 13 years.

It looks like there are gasket kits available, Honda p/n 16010-426-305, but what I'm wondering is if it's possible to get these in a set of 4.  I still need to call the dealer, but I'm pretty sure these are ~$35 each.It seems the CB650 with piston carbs (Keihin PD50BARH7, with a square around the A and the 7 looks like Japanese) truly is the redheaded stepchild... the part number only brings back '79 CB650, and '80 CB650 and CB650C.  P/n compatibility search done here, prices cobbles from other sources.

Any advice on whether or not to just cough up the cash, or is there a way to rejuvenate old gaskets, or should I spring for a total rebuild kit?

Also, I've been studying up on soda blasting.  I can handle building a soda blaster like this one.  I wonder if there are any extra tips to go with this procedure.  I remember reading somewhere on the forum about using vinegar or an ultrasonic cleaner to put the finishing touches on it.

[B.O.X.N.I.F.E.]

The 650 experts may know better, but I've not heard of any cheap 650 kits. They are just plain expensive. Rejuvinating hardened rubber gaskets & orings may be possible with the wintergreen oil thing, do a search for that.

For carb cleaning, I've never seen a set so bad that Berrymans won't clean them. I rebuilt a set that had sat since '78 full of gas. By far the worst carbs I've seen. The deposits were rock hard, it had past the sludge or gooey stage years ago. Took about 4 days soaking in Berrymans and they were good as new. Nothing cleans better in my experience.

I've been trolling the web for a carb gasket kit on my 1980 CB650C.  As seen in the previous post, gas gushes out of the #4 overflow like it's a faucet, and I need to clean the carbs anyways.  I figure as long as I've got the carbs out and apart, I may as well take care of the gaskets, since it sat for 13 years.

It looks like there are gasket kits available, Honda p/n 16010-426-305, but what I'm wondering is if it's possible to get these in a set of 4.  I still need to call the dealer, but I'm pretty sure these are ~$35 each.It seems the CB650 with piston carbs (Keihin PD50BARH7, with a square around the A and the 7 looks like Japanese) truly is the redheaded stepchild... the part number only brings back '79 CB650, and '80 CB650 and CB650C.  P/n compatibility search done here, prices cobbles from other sources.

Any advice on whether or not to just cough up the cash, or is there a way to rejuvenate old gaskets, or should I spring for a total rebuild kit?

Also, I've been studying up on soda blasting.  I can handle building a soda blaster like this one.  I wonder if there are any extra tips to go with this procedure.  I remember reading somewhere on the forum about using vinegar or an ultrasonic cleaner to put the finishing touches on it.

[Frankenkit]

yeah, they're kind of a pita to find.  $35 is a decent enough deal on the parts and if you only want to do it once, go with the OEM ones.  you shouldn't be disappointed.  for air cutoff valves and accelerator pump, you will want to go with another distributor- I think I did Siriusconinc.com.  

Gasket rejuvenation is iffy, and these carbs are a real pain in the rear to rebuild.  I've got it down to breaking the rack, completely dismantling, cleaning, and reassembling in 4 hours, but it's not a whole lot of fun.  I attained this skill via repetition- and the repetition via trying to cut costs.  do it right the first time and maybe you won't have to do it too often.

[Frankenkit]

oh and for the love of god, don't break the unobtainium black plastic choke lever. 

[MickeyX]

If you want a good read, try Kit's CB650 build. It's a real hoot. Yes, it is 38 pages. 

http://forums.sohc4.net/index.php?topic=30602.0


Hush's build was pretty good too. Lots of laughs. 

http://forums.sohc4.net/index.php?topic=35024.0


BTW, they were co-winners in the Feb Bike Of The Month this year. 

There's a good read on the charging/hot start issue too. just look up "hotstart".

[MickeyX]

yes, that black plastic doohickey is like gold. Can't buy them separate, can't find them anywhere. they break easily. don't ask me how I know. 

[JimJamerino]

I might just try reusing the old gaskets to start with.

Since I have an extra carb rack, maybe I should take the black plastic choke thingy and see if I can get a machine shop to make a metal one.

Thanks for the advice, y'all.

[The_Crippler]

Since I have an extra carb rack, maybe I should take the black plastic choke thingy and see if I can get a machine shop to make a metal one.

That's a solid idea right there.  If they can make one, they can make more, and you might find some takers on here. 

[Frankenkit]

lots and lots.   

[The_Crippler]

Especially Yesterday Kit and her Time-Traveling Motorcycle of Doom.

[Frankenkit]

  no kidding, man. Nothing like having your carbs all together, installing them, and *SNAP!*

...then having to dismantle them AND your spare set just for that little plastic bit.

[The_Crippler]

I'm ashamed to say that I've never read your log word-for-word...just skimmed and looked at all the pretty pictures.  Can you give us a ball-park of which page range we should look for this part?  I've heard mention of it a bunch, but can't for the life of me think of a plastic part on those carbs that fits it.  (I figure, if I don't know, someone else reading this thread might also not know.)

[JimJamerino]

The black thing in the middle of the carb rack is where the choke cable hooks up.  I was unaware of this, but apparently it is rather fragile.

[Frankenkit]

it's VERY fragile.  I suggest hooking up the choke and pulling the choke lever up on installation to pull that fragile lever up and out of the way of all the hard, mean rubber bits.

[The_Crippler]

Hmm...this is very strange...I've had my rack on and off, hooked and unhooked, and I've never noticed that bit...and my choke works perfectly fine. 


Looks like I know what I'm exploring again this weekend...