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Discussion Starter · #1 ·
Hello,

I'm on a crash course reading all the old posts and archives here, but there isn't time to get to them all. Looks like a fine, friendly forum though!



Within a couple days I'll be checking out a '79 CX500 and I'm trying to find out what I should check for on this oddball motor. I see from posts here that there is a possibility that trying to run the bike on a dead battery will fry the charging system. Well this bike is advertised with a dead battery; I was going to start it with the battery from my '86 VFR700.

Is jump-starting this bike a bad idea (from another motorcycle and not a car, of course)?

I've read several posts about failed stators; is this a deal-breaker? What about this CDI thing?



I keep hearing about the water pump seal, too. An issue here? Any way to tell? How hard is the repair?



I've had over 10 years' riding experience and do all my own maintenance on my bikes; chassis bearings, carbs, valve adjusts and general "freshening up" don't bother me.

But I don't know much about this engine's weak points, so if you can tell me what to look for I would certainly appreciate it.



I had a chance to ride a ragged-out CX500 years ago and found it to be a torquey hoot of a motorcycle; so if this bike is a solid platform mechanically, it looks to be cosmetically more or less complete and I'm hoping to bring it home to my geriatric stable.



Thanks a lot for the help...
 

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A couple of answers for you. It shouldn't hurt the bike to run it with a dead battery. The stator supplies the ignition current, and a different section of the stator provides the charging current. I would leave the old one in and jump from another battery. It doesn't make any difference if it is a car battery or bike battery. 12 volts is 12 volts.



Failed stators do occur and are a bit of a pain to remedy as the engine needs to come out. Engine removal is a couple hour project the first time and then rear case removal and parts replacement is another couple of hours. A lot of us do a "triple bypass" when we have the engine out and apart. (Stator change out, waterpump seal, and cam chain replacement) Doing all of these on your bike will cost approx $350.00 in parts and gaskets. And about 8 hours in dedicated time. Maybe more the first time or two.



The water pump seal, aka, mechanical seal, can be replaced without engine removal. Alternative seal (Davy, Yamaha) cost about @25.oo and can be replaced in a couple of hours. A brown stain and coolant leaking onto the engine below the left carb is the clue to a bad seal. Sometimes these re-seal themselves after a few miles, but not always.



The CDI is what takes the electrical energy from the stator and then provides a electrical pulse to the coils at the proper time for the spark plug to fire. They do go out, or get weak. New ones are not available, used ones on the "bay" are about $100.00. There is a work-around product called ignitech that replaces the CDI box and draws current from the battery for it's power. It seems to work well and if your stator is still providing a charging current, you may not have to change the stator out.



I would use the above information to adjust the buying offer to the seller. A average condition 79 CX is probably worth $1000.00 - $1300.00 if you know the stator, water pump and cam chain are good. Then down from there, depending on what is wrong. I have purchased several over the last couple of years from $100 - $300, depending on what was wrong. Prices seem to have increased in the last year or so tho. You may have to search for decent restorable $200 bike. Personally, I would shy away from bikes that have been bobbed, cafed, chopped or stretched. To much opportunity for unsafe modifications and creation of run ability issues that are difficult to solve.
 

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Coffe_brake:



We look forward to welcoming you to our site. Good luck with your prospective bike inspection.



If you review the fixed threads on the general discussion forum, you'll find a wealth of information on the CX/GL bikes.



Yes, the motor is torquey...that's why we love them. They're also easy to work on.



Other's will chime in with their thoughts....here are mine.



The weak points of this bike? Firstly it's not an oddball motor - it's actually a very good and efficient motor developing high horsepower per cc in comparison to other motors. You may hear tappet noise. It's easy to adjust the tappets on this bike as they are literally "in your face". We like that. It's not a weak point at all, rather a strength. Almost nobody reports issues with pistons or valves. These motors last a long time (with regular peroidic oil changes and maintenance).



Carbs tend to be touchy on all these bike (aren't all bikes like this?). They need to be clean and properly adjusted. Once done, you're riding in the clouds. Some people have difficulty with this. Great thing is, we do have some carb experts on line.



When on your bike inspection, take a spare motorcycle battery with you, in good working order. It should have around 12.5 + volts showing across the terminals. With the bike's kill switch turned off, crank the motor and measure the voltage drop. Possibly down to 9.5 when cranking. Then with the bike running and at 2000 + RPM, measure the voltage again....should read 13.5 - 14.5 but not higher than 14.8. This is a brief test to see if the charging coils on the stator are working and that the regulator is working. I believe on the 79's the stator also has low and high speed coils with which can best be tested on the open road at slow and high speed. If the stator needs changing, it involves a complete motor drop. There are other tests you can do and again, the information is on the site.



If a motor drop is considered, most will do Timing Chain, Water seals (all O rings), starter motor refurbishment, stator, possibly clutch, although you don't need to drop the motor for either the clutch or starter motor. In fact, the clutch is super easy to access on these bikes.



Starter motors are identical for 500's and 650's, however the large bike tends to be a bit tougher on the starter motor.



Look in the tank for rust. There are ways to clean it out, but it just involves a bit more work. This should/would not deter you from purchasing the bike.



Forks are no better or worse than any other bike - in my opinion. Same with brakes.



Enjoy!
 

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So long as the engine has no major mechanical rattles you will find them a joy to work on especially compared with a VFR.

There's little or nothing not known about the bikes and sources for decent priced parts.



My 2 cents
 

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Welcome to the group!

Most of your initial questions are answered in THIS LINK and as previously mentioned, the General Discussion section has the Quick Reference thread that has that link and tons of other helpful information, including links to factory service manuals that can be downloaded.



If the cosmetics are decent, chances are the internals are pretty good too. Although I can't physically do much myself due to my hands, these bikes are about the easiest to work on of any vintage machine out there, and they keep popping up out of the woodwork or barn. Some parts are a bit hard to find, but most are obtainable with diligence. Aftermarket items are not difficult to find either.



And the bottom line is that you have stumbled upon the premier resource right here for assistance. That said, take a moment to update your profile with your location and add any bike information to the signature line. You never know when someone is around the corner.



Good Luck!



Joel in the Couve
 

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Discussion Starter · #6 ·
Thanks folks, a whole lot.



It's a busy day, a good riding friend is nervous about buying a KLR from another good riding friend who lives far away, they haven't met yet. They're coming to my house for lunch to meet each other and do the transaction. If I can get 'em out happy and riding in time, I'm going to look at the Honda this afternoon.



Appreciate the links, and especially instructions on how to test the stator. I'm not sure if the VFR battery will fit, it's the smallest battery of my three bikes: a Concours ZG1000, and a Bandit 1200, along with the "rescued" VFR, it was in terrible shape when I got it but runs great now. That's why I have high hopes for the CX, if it hasn't been mangled or neglected too much.
 

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Just take a set of jumper cables and a can of starting fluid along. Jump from your vehicle (most say not running), after a shot of starting fluid down the air intake. Check for proper oil level before doing this. You should get a couple of seconds of running even without fuel in the tank. Enough to tell if the engine is free and the ignition works anyhow. Don't overdue the starting fluid, and I would also crank the engine until the oil light goes out before I flipped on the kill switch.
 

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Discussion Starter · #8 ·
Thanks everyone, after a nice visit, I got my friends out of the house just in time for a massive thunderstorm. Seller is out of town for the evening, it will have to wait till tomorrow.

I've gone through the advice a few times; I think I will know what to look for.
 

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Discussion Starter · #9 ·
OH MY GOSH I WANT IT SO BAD!!!



I just got back from looking at the '79 CX500, and it was about what I expected.



There are a few problems:



A gutted Screamin Eagle Harley exhaust has been (poorly) installed, without re-jetting. It pops and hiccups on decel, presumably from a lean condition.



The carbs show evidence of a partly clogged low-speed jet; the left side misses a lot at low speeds but picks back up at higher RPMs. The fact that it only misses on the left side excludes a bad coil, right?



The steering stem bearings are so far gone that the front end of the bike wanders in the road. The owner doesn't notice it (he has not ridden much), but he was kind enough to hold the back end down while I wiggled the front wheel; it moves over an inch in either direction. And the front tire is dry-rotted.



I'm not sure if it's got the original rear shocks, but the back end squats super low.



The clear coat is understandably cooked off the tank. Traces of the break-in sticker are still there.



The good:

I see not one single place where the wiring harness has been cut or mangled. Even went under the seat and fender looking for it.



The water pump leaked the predictable little bit of fluid after sitting up, nice and clean, the seal seems good.



Cosmetically, it's intact but it's been sitting. The seat cover's torn. The signals are sagging. It's dirty all over and all aluminum surfaces are moderately oxidized. Only 11k miles but it looks its age.



Owner's a nice guy, family man and all that, he was real patient and answered all my questions honestly. He's asking $900. Is that too much?
 

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Here is what I would do. I would send him a e-mail with the following information:



Items and cost to restore bike to current safety standards.



1. New front tire $80.00 cost plus $35.00 for mounting and balancing. ------------------------------------------------$115.00.

2. New stem bearings $45.00 plus 5 hours of time @20.00 per hour -----------------------------------------------------$135.00

3. New mufflers/collector box (Honda brand) $400.00 plus 4 hours labor -----------------------------------------------$480.00

4. Complete carb cleaning by Larry. (including UPS) -----------------------------------------------------------------$275.00

5. New seat cover or repair of original ------------------------------------------------------------------------------$150.00

6. Rear shocks (?) maybe, maybe not ---------------------------------------------------------------------------------$100.00

7. Clean up supplies $25.00 plus minimum of 20 hours @ $20.00 per hour ---------------------------------------------$420.00



Minimum total cost to restore -------$1675.00



Considering that this bike would be worth a maximum of $1500.00 when completed, I will concede the labor cost and use only the hard cost of replacement parts. This would be $925.00 for the parts. Let's say that you will easily find another $75 of needed parts and call it $1000 total parts. Subtract $1000 from the $1500 max value when done and my offer is $500.00 for the bike in current condition.



I would probably even offer him less, maybe $400.00 just to test the waters. And don't be afraid to leave an offer on the table for a couple of days. Often times you will get an acceptance of your offer. And don't let him know that "you want it so bad"
 

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Hi Coffee_Brake,



I noticed this thread & thought the name was familier, I am also on VFRD, I think if you get this bike you will not be disapointed, they are a blast easy to work on, run forever....



Good Luck, If you anything I have got a 80 parts bike with not much off her...





Gary

V-FORE
 

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Discussion Starter · #16 ·
Haven't brought it home yet, that's why there's no photos. My very patient and understanding husband has finally put his foot down that some other unused parts get gone out of the garage before the CX comes in, I'll be spending today lugging out junk to make room and picking up likely Monday.

Our garage is small, we have to keep it tidy or it would be useless.



It's all there, except that awful exhaust. I've ridden the bike; it must have new neck bearings and a new battery. The carb bowls are leaking but they are still streetable. Oh, and the rear running light is out. All else seems OK to run.



So...I need the collector and cans, as I understand it.



I might be after a part or two Gary, but hopefully not much. This bike may look its age but it's a lot more intact than that poor unloved VFR was when I got it!
 
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