'78 CB650 Custom not running

If it's broken or just needs tweaked

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CrisW
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'78 CB650 Custom not running

Postby CrisW » Fri Apr 18, 2008 4:19 am

Hello everyone!

I'm new to this site and I would really appreciate input! So today I bought a 1978 CB650 custom for $200. It needs cosmetic work and it is not running. Not to mention that I don't know much about bike work. The person I bought it from said that his son had it running two years ago and that all it needs is a new solenoid starter. My dad is a mechanic and he will be helping me put new parts in. I have a few questions:

1. Should I start out by getting a new battery and starter solenoid?
2. What else should I work on before starting it up?
3. Is the solenoid difficult to replace?
4. I noticed immediately that 4 cables are hanging out of the right side of the bike. Shall I assume these go to the carburetor?

Any help is much appreciated. The bike is 30 years old but is pretty cool and has a lot of potential. I thought it would be a great project. I hope I'm right!

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Volker_P
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Re: '78 CB650 Custom not running

Postby Volker_P » Fri Apr 18, 2008 4:54 am

Welcome here! :D
I would be careful with PO statements like "all it needs is this or that" especially when cables hang out of the bike! :shock:.
Be prepared to check everything important before riding or running the engine. E.g. you should clarify if the brakes work and do an oil change and so on. Please have a look on previous articles what to do, I am a bit busy at the moment.
Changing the starter solenoid would be a simple job, however usually rather the starter clutch or even the starter transmission make trouble which is more difficult.
Don't hurry but get it running step by step. The CB 650 is not susceptible at all, however riding with very bad adjustments or defective parts may have consequences soon like for most motorcycles.
With regard to find out the year, this link may help: http://www.motorera.com/honda/
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

cb650
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Re: '78 CB650 Custom not running

Postby cb650 » Fri Apr 18, 2008 7:36 am

Carbs should only have 2 cables. 1 pull and 1 push. Clean out the tank also no sense putting any crap in the carbs. Read your manual. post a pic of it so we can tell you the model. Where are you? US verions where diff than most that went to the rest of the world.
Did you clean the tank out?!?!?!?!

CrisW
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Joined: Fri Apr 18, 2008 4:02 am

Re: '78 CB650 Custom not running

Postby CrisW » Fri Apr 18, 2008 2:21 pm

Thanks so much! Yes I am aware that this bike may need a whole lot more than I originally thought. And I am going to work step by step. I'm going to start out by cleaning and sealing the gas tank. Someone said I should start out by cleaning the carbs too but I may have someone else do that for me. It may be too much for my amateur hands! Then I'll have to figure out where those four cables go :?: ! I'll post a pic of it tonight and maybe someone can help me figure out if it really is a '78!

CrisW
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Re: '78 CB650 Custom not running

Postby CrisW » Fri Apr 18, 2008 2:22 pm

P.S. I'm in Oakland, California.

cb650
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Re: '78 CB650 Custom not running

Postby cb650 » Fri Apr 18, 2008 6:06 pm

chances are you have a 79Z US model. The haynes manual starts from 78 and some counties list the bike year when sold not acual manufactures year. No custom or standard just a Z. Some people call them a custom because of the comstars but all of them where the same. Honda didnt split the 2 untill 80 in the US. Your rear wheel should be a 17" reverse (black) comstar. Only year for it on 650. Cables are most likely the throtles and choke and clutch. Sounds like someone changed handlebars and didnt finish. Does your seat bolt on or is it hinged with a lock?
Did you clean the tank out?!?!?!?!

CrisW
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Joined: Fri Apr 18, 2008 4:02 am

Re: '78 CB650 Custom not running

Postby CrisW » Fri Apr 18, 2008 8:42 pm

Well I finally got enough of the dirt off the bike to find the VIN! Turns out the bike is a 1980 and was manufactured in Japan. As for the mystery cables, it does look like they are hanging off the carburetor. Time to flip to my owners manual :?

cb650
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Re: '78 CB650 Custom not running

Postby cb650 » Sat Apr 19, 2008 7:24 am

Owners manual wont say much. You need a repair manual.
Did you clean the tank out?!?!?!?!

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Volker_P
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Re: '78 CB650 Custom not running

Postby Volker_P » Tue Apr 22, 2008 2:34 am

... e.g. like the one Cosky is friendly to share:
http://cosky0.tripod.com/
http://cosky1.tripod.com/
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

CrisW
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Joined: Fri Apr 18, 2008 4:02 am

Re: '78 CB650 Custom not running

Postby CrisW » Tue Apr 22, 2008 3:51 am

Thanks so much for the link to the repair manual! I'm going to start out by cleaning the gas tank and carbs and buying a new battery. I'm hopeful that I can get this thing fired up. With a little TLC and cosmetic work this could be a great bike.

soos
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Re: '78 CB650 Custom not running

Postby soos » Tue Apr 22, 2008 8:20 am

What style carbs do you have?

Are the tops of the carbs round, or oblong?
Being an '80 frame, it should have a 16" rear.
If it has a 17" rear congrats... the 'late 80 through the '82 frames(SOHC) are all the same... the '79's is different.
The '79cb650 std. is a rare one among cb650's.

$200?
Not a bad deal if it has a clear title!

And as Volker_P said, don't ever trust a P.O.'s word for a condition of a bike. EVER....
I would literally(and have on 2 cb650's) checked everything that moves/swings/pivots before trusting it over say 15-20 miles an hour.

Good luck, these are nearly bulletproof bikes. Just more maintenance intensive than more modern rockets available out there.



l8r
-=≡ Soos ≡=-

CrisW
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Re: '78 CB650 Custom not running

Postby CrisW » Fri Apr 25, 2008 3:20 pm

Well my Dad pulled the bike apart and it looks like it isn't an easy fix like I was hoping. It appears that the starter clutch is shot and I don't know if I want to invest any more money in the bike. I was pretty bummer out :( . If anyone knows of anyone in the San Francisco Bay Area that wants a cool project bike please let me know!!!

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Volker_P
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Re: '78 CB650 Custom not running

Postby Volker_P » Tue Apr 29, 2008 1:29 am

Sorry to hear that.
However the starter clutch (if it is not starter transmission gears) can be repaired with the engine in the frame which means much less work compared to separate the crankcase halves. The trick is to pull the primary shaft and disassemble the torx bolts before you get the clutch out in parts through the oil pan opening. It seems that the three springs for the rollers get weak and then it starts slipping. replacing them may already do the job. I never did it myself so I can't provide more details, but some here did. You may find hints using the search function. I would guess this is no real beginners job, but not difficult with a bit mechanic experience.
If your dad is willing to help, I would think it is worth to get the springs and have a try. :wink:
But first remove the oil pan and check whether the starter transmission gears still have all teeth. Possibly the upper gear still turns when you turn the rear wheel backwards on the main stand. With the starter removed, you might see through the opening whether it is still intact then. Replacing a starter transmission gearwheel would mean splitting the crankcase however. :?
Cosky's great (free) online manual: http://cosky0.tripod.com

forum links to common technical issues

If you really like this site and you would not like to see it vanish soon, have a look there: Urgent: Future of HondaCB650.com Forum

cb650
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Re: '78 CB650 Custom not running

Postby cb650 » Tue Apr 29, 2008 8:10 am

I took one out of a parts bike and it is possible. Not easy though.
Did you clean the tank out?!?!?!?!


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