[oldnubie]

Let me introduce myself, I am an old rider (I have the scares to prove it) however a newily entering the two wheeled scene also I am looking to purchase a good CX.

I am considering buying a 1980 CX500 that the owner says has a bad coil and will only fire on one cylinder.

I will verify compression with a compression tester to make sure the problem is not an internal engine problem.

If it is a coil what does it cost to fix?

Is a bad coil a common problem for this bike?

Are the parts available?

I can verify one side is not firing on the non runing side while the bike is running by pulling a plug wire and checking for spark?

Is there a quick check to see if it is truely the coil or another part?

I used to ride a CX back in the 80s when they were new. I appreciate their smoothness and reliability.



TIA



Oldnubie

 

[Cobram]

The coils are pretty much bulletproof, not saying it's not the coil, but it almost never is on a CX.



Swap the coil wires at the bullet connector, and check for spark, you may find you have spark at the "dead" coil. If you get spark at the dead side, this will also rule out the wire and spark plug boot.



Most likely a dead CDI unit, bad pulser inside the engine, or both.

 

[thackney]

You will need to move the coils from side to side on the bike to see if the misfire follows. Make sure you keep the wires coming from the CDI on the same side as they are now on. If the misfire follows the coil change, new aftermarket coils are available pretty cheap (search this site). If the misfire does not follow the coils then the CDI, pulsers or stator could be at fault if I remember correctly.

Bad carburetion can also cause one side not to work. You can verify firing by connecting a plug to the plug wire and cranking the engine while watching for a spark. You need to ground the plug to the head or block or other known good ground. The valve covers have rubber gaskets and are not suitable.

You can download the service manual from the tagged lists in general discussion forum under quick reference.

 

[oldnubie]

Thanks for the tips, ya'll are helpefull and fast. I looked on line and found a Coils, Stator, CDI and Pulser.



I am going to guess the stator in on the back of the engine. I have changed stators on traditional transverse crankshaft.



How dificult is it to change a Stator on a CX? Do you have to drop the engine?



oldnubie

 

[thackney]

Yes, the engine needs dropped, but do the diagnostics first, may be a bad coil or a carb issue.

 

[marshallf3]

Yes, the engine needs dropped, but do the diagnostics first, may be a bad coil or a carb issue.

Agreed, a simple ohm meter can provide some pretty reliable results when testing the stator according to the procedure.



There's really no excuse not to have a meter in your tool kit what with Harbor Freight putting the things on sale as low as $2.99 from time to time, matter of fact the last one I got was free so long as you spent $10 on anything else even if it was some sale items. It pays to get on their mailing list as it does to browse their website from time to time. If you see something shown as being on sale on their website be sure to print the ad out as the local stores often have not a clue what's on sale online.



Highly disorganized store but often some reaqlly decent deals for the money. The wrenches and more expensive of their sockets and drive stuff is getting rather good but they do stupid things from time to time. For instance I love their long handled open/closed wrench sets, however the metric set omits a 13 mm in favor of a size that's rarely used for reasons unknown.