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New to the forum, but I have read many threads over the past couple months. Everyone seems very helpful, so I thought I would pose a question.



My short question is this: Where can i find a new set of valves for my '80 cx500? And how much should I pay for them? Am I going to have to search junkyards and parts bikes for them or is there an easier way?



My long story is this: This is the first ever motorcycle that I have had. I originally bought it because I have a fairly long commute to work and a gas hungry car. I learned how to ride it on the way home from the house where I bought it. (for 500$) It was scary as hell, but I made it home. The next three times I rode it, I finally got why people are obsessed with motorcycles. I felt the wind whip around me and I was hooked. I only got to ride it 4 times, because the second time I took her on the highway it overheated. I was watching the temp gauge, and it seemed fine until I felt a loss of power and noticed steam coming from the coolant overflow tubes. The engine shut down and I assumed the PO hadn't put coolant in it. So I went to the gas station, bought some premix, and put it in the coolant reserve tank. (Maybe I should have put it right in the radiator?) The bike had about 25 mins to cool from when I left it to when I got back with the coolant. I started the bike up and whoo hoo! It started. I gave a cheer and walked the bottle of coolant back to the car. Before I shut the trunk I heard the motorcycles engine die. When I ran back over, no amount of coaxing would get the thing running again. I ended up having it towed to a shop who said they would do a compression test on it for me for free. He said the results were 125 in one cylinder and 90 in the other. I asked him what he thought it could be, he said it was probably that it burned a valve. He said it would be around 500$ to fix it.



Since I only paid 500$ for the bike, I am wondering if it is going to be worth fixing or if it would be better just to junk it. I have the money, and I don't mind spending it as long as it will actually fix the bike. The shop also seems kind of shady, and I am wondering how difficult this would be to do myself. I don't know alot about it, but it seems like it wouldn't be that much harder than adjusting the valves, which I am confident I could do myself.



Thoughts?



btw, Make sure my profile is updated with my location and bike type. I think I did it right....
 

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Hi Mrkump,... I wouldn't put $500 into a $500 bike, UNLESS 1) You've studied it throughly, AND it makes viable economic sense. These bikes offer a low return on economic investment, and often only make sense to fix if you do the labor yourself.

In the General Section of the Forum, -Quick reference material for new members 'there is a reference to Used Bike Evaluation. (costs and systems to evaluate and general costs)'



If you evaluate the bike (using that information) you'll decide if it makes economic sence. Good Luck
 

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First, good job on your profile location and bike model. I just wish everyone would do the same when they register.



I would not start buying valves at this point. More examination needs to be done first. Can you turn the engine with the crankshaft bolt under the radiator? If it turns, you are a lot closer to success. If it turns I would squirt a couple of tablespoons of ATF down each sparkplug hole and let it sit for a couple of days. I think that maybe the overheating has caused the rings to bind to the piston. Hopefully not permanently, the ATF may free things. Even if you can't rotate the engine, add the ATF in the plug hole. If the rings are binded to the cylinder, you may also get lucky. There is also the possibility that the overheating has caused the rings to friction weld to either the pistons or cylinder walls. ATF won't help that out.



If you get the engine to rotate, I would renew the oil, coolant and fuel and try starting it. If the rings are stuck, it may take a lot of miles for them to shake loose. I would say try 50 or so gentle miles if you can and then check the compression. Compression should be checked on a warm engine, throttle wide open, kill switch off, and cranked until the reading stops rising.



Keep us in the loop on this, inquiring minds want to know. And welcome to the forum!
 

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Hi,

You should always check/add the coolant at the radiator,,don't go by the overflow bottle. When you added coolant to the ovorflow bottle and then started the bike that would not have put any coolant into the rad or engine. Running the engine without the coolant may have caused problems as Blue Fox mentioned, or it could also be a bad head gasket on the side that is reading low,,valves would be less likely in my opinion.
 

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Welcome to the forum.



As much as we all like these bikes, it rarely makes economic sense to pay somebody else to work on them. You'll have significantly more tied up in it than it's worth in short order, and then the odds are very good that something else will fail that costs even more. There are certainly exceptions, such as a well-maintained bike or a barn find, but these are not the typical bike bought for $500.



No way would I pay anyone $500 to replace valves on a $500 bike, even more so not knowing what else may need attention. If you have a hunch the shop is shady (or even mildly incompetent), you're probably right. Listen to that inner voice.



These bikes are actually pretty easy to work on. If you're even the least bit mechanically inclined and willing to learn you can do the work yourself. There is a wealth of information here on the forum and folks will be happy to jump in with good advice.



Regarding the valves, did you watch the compression test as it was performed? The throttle must be held wide open when performing the test - if not, then the numbers are often close to those mentioned. This is a common mistake.



If it is certain the valves are bad you can probably get a whole used cylinder head from ebay for around $25. Or worst case, a complete engine for a couple of hundred bucks.



There's something to be said for getting that first bike really cheap, even if it's severely ragged out, and getting it on the road for next to nothing. But if it needs many things, a well maintained bike in good condition is almost always a much better deal.



Can you post some photos of the bike?
 

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Don't junk it.



Go through the bike and check things over to makes and make sure the valves are going up and down when they should when rotating the engine with a ratchet at the inspection cover under the radiator.



90 and 125 isn't that bad either because the test should be done on a hot engine so it should go up higher. My compression is only 100 on both sides and it runs fine.



After you check everything over try to start it again. If for some reason it doesn't start spray a bit of starting fluid in the air box and see if it runs. If so it's the carbs. You can also check the coils.
 

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As per above and consider these 2nd and 3rd+ opinions e.g don't take the mechanicals words as gospel.



If it were me I just get the heads off first to see what the real damage/problem and then post back.If it is just a valve or two and there's no there's damage then a head gasket set and a couple of 2nd hand heads will be less than $200 I reckon if you shop carefully.Couple on Ebay going cheap,



http://cgi.ebay.com/ebaymotors/Suzu...7048935QQptZMotorcyclesQ5fPartsQ5fAccessories
 

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I agree with the other forum members -- fill up your cooling system at the radiator on a CX500, never at the overflow jug. Next, check the oil. Put you bike on its center stand on level ground. Unscrew to dipstick, wipe it and put it back in without screwing it down. Now read to level on the stick. Do not screw the dipstick in to check the level. What does the oil look like? It should be light brown.



Then try to get the bike running again however you can. Spraying a little blast of starting fluid into the carbs while trying to start it has often worked for me.



I'm skeptical that you burnt a valve. I've been on this forum for several years and I've owned four of these motorcycles. Burnt valves are not common on these motors. Other stuff goes bad, but not commonly burnt valves.
 

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i am thinking coils or crap from the fuel tank but like everyone else has said try to rotate the engine and DO NOT PUT 500 MORE IN TO IT there is a crap load of help here all you have to do is ask
 
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