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Discussion Starter · #1 ·
Hi all, I got my bike last June (and have been lurking about until now). I've put about 450 mi on the bike this year on short rural runs. I believe it has some carb issues but has been rideable. Initially wouldn't go above 50mph/~5k rpm, replaced plugs/caps and could reach 55+mph (didn't push it-I've still got my training wheels on.




Last week I did the the tappets/cam per Shep/Lucky/FSM (yes I had all three in different tabs on my computer next to the bike). Any afterwards it seems stronger on the lower end (jumped right up to 3k rpm) so a buzzed around town to get a feel for it. After a little bit it begam to labor and balk and didn't want to go, so I limped home nursing the choke/down shifting just trying to keep revs.



Rats did I screw it up? Cheese & rice I must have really botched the adjustments (so I thought). Rechecked everything today and setting seemed okay but I went through it all again. Started just fine (with the usual choke). Let it run while I cleaned up and changed to take spin and see. No way, it had died; restarted roughly and struggled and quit.



Huh? How does it not want to run now, I don't understand, it makes no sense. HELP!



Okay I'm ready to listen now. TIA
 

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How old or new is your battery? If it ran well at first and then started having issues I'd look at fuel supply maybe? Does it run ok on choke and then have trouble without it?
 

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Your work may or my not have caused the problem.

First, be sure you really had the left cylinder at TDC on compression stroke. The valve rockers should all rock some by hand. Cam chain is adjusted from this same position. Then rotate to right TDC and repeat adjustments. If you are sure you followed this procedure then your work is not at fault.

I would first check that the fuel petcock is properly attached, vacuum line to the frontmost nipple on the engine side of the petcock and the vent hose on the rearmost nipple. Make sure the vacuum hose is attached on the R intake "manifold". If that is OK, disconnect the fuel hose from the carb inlet open the petcock and apply vacuum to the petcock with a pump, your mouth, or crank the engine with the kill switch on. Fuel should flow freely in a good stream from the fuel hose. If not, fix the petcock.

Check your spark plugs.

Now, if you have fuel, valve adjustment is proper (so timing is OK), and there is compression the next is ignition.

You have a CDI bike and it could have failed. Look in the service manual and this forum on how to check the stator. If is OK by resistance checks, the CDI could be bad, but the only way I know to check it is by substitution.

Since you could not get above 5000 rpm last year, my gut feeling is the CDI.
 

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Discussion Starter · #4 ·
How old or new is your battery? If it ran well at first and then started having issues I'd look at fuel supply maybe? Does it run ok on choke and then have trouble without it?
New battery this year



Drained tank, pulled petcock, checked strainer today - OK



Before adjustment needed full choke to idle ~1 min, then half choke til it warmed up (~5min) then none; after adjustment needed less/little choke to idle cold, once it starts to register on temp gauge it begins to stumble adjusting choke only helps for few moments then no choke, nothing lasts and back and forth. Different degrees of bad from moment to moment.
 

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Discussion Starter · #5 ·
Your work may or my not have caused the problem.

First, be sure you really had the left cylinder at TDC on compression stroke. The valve rockers should all rock some by hand. Cam chain is adjusted from this same position. Then rotate to right TDC and repeat adjustments. If you are sure you followed this procedure then your work is not at fault.

I would first check that the fuel petcock is properly attached, vacuum line to the frontmost nipple on the engine side of the petcock and the vent hose on the rearmost nipple. Make sure the vacuum hose is attached on the R intake "manifold". If that is OK, disconnect the fuel hose from the carb inlet open the petcock and apply vacuum to the petcock with a pump, your mouth, or crank the engine with the kill switch on. Fuel should flow freely in a good stream from the fuel hose. If not, fix the petcock.

Check your spark plugs.

Now, if you have fuel, valve adjustment is proper (so timing is OK), and there is compression the next is ignition.

You have a CDI bike and it could have failed. Look in the service manual and this forum on how to check the stator. If is OK by resistance checks, the CDI could be bad, but the only way I know to check it is by substitution.

Since you could not get above 5000 rpm last year, my gut feeling is the CDI.
I pretty sure I did the cam chain on the wrong side (right). I watched the vavle action to get compression stroke (exhaust rockers, intake rockers, compression stroke).



There's no vacuum lines on petcock since I had it (it does have two nipples).



Have no idea if it's CDI/TDI. Have HF Battery/alternator condition tester wired to battery, shows green when rpm @ 2k



New DR8ES-L w/new plug caps (non-res).
 

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The TI ignition wasn't in the CX until '82, so you are CDI. You need the vacuum line to the carb and petcock for fuel to flow unless the petcock was modified to work with out it, i.e. the diaphragm turned the other way and the spring reversed. Another thing to check is the vent hole in the gas cap to make sure you aren't getting a build up of vacuum in your tank.



Joel in the Couve
 

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Your stator is charging, but that doesn't show condition of the CDI coils on the stator.

Open the petcock with the fuel hose disconnected from the carbs. If it flows freely then the petcock has been converted to non vacuum. Check to be sure the vacuum port on the right intake "manifold" is sealed.

Reset the cam tension using the left side as reference and do the ignition system checks described in the service manual and here.

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=17&t=521
 

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Discussion Starter · #8 ·
Your stator is charging, but that doesn't show condition of the CDI coils on the stator.

Open the petcock with the fuel hose disconnected from the carbs. If it flows freely then the petcock has been converted to non vacuum. Check to be sure the vacuum port on the right intake "manifold" is sealed.

Reset the cam tension using the left side as reference and do the ignition system checks described in the service manual and here.

http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=17&t=521
Fuel flowed when I drained it yesterday, can't say that it was "freely" though. It flowed better when I switched it to reserve setting. There wasn't a lot of fuel in to start with (<1 gal). Do I need to install a vacuum line then?



Will examine vacuum port closely for seal/cap.



Will redo cam chain "correctly" this time (hopefully), so apparently I didn't do any permanent damage?



Need to do my homework for the igintion checks first.

-----------------------------------------------------

I appreciate everyones guidance & patience. TYVM
 

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Sounds like the petcock was converted, make sure the vacuum tap is closed.

Don't think there is any harm to the cam chain, in fact I question why left tdc would be any different than right tdc,but that is the recommended procedure.

The resistance measurements are done on the STATOR END of the CDI connector. Some have done them on the CDI side, that doesn't work.
 

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Discussion Starter · #10 ·
Okay, finely did ignition/stator check per Blindstitch's diagram.



1. RH low speed coil

2. RH high speed coil

3. LH Adv Pulsar

4. LH low speed coil

5. Ground

6. LH high speed coil

7. RH Adv Pulsar

8. Source coil high speed

9. Source coil low speed



(Acceptable Range) - My Measurement



1/5 (95-116) - 126

2/5 (81-99) - 107

3/5 (185-225) - 219

4/5 (95-116) - 122

6/5 (81-99) - 104

7/5 (185-225) - 223

8/9 (77-95) - 92

5/9 (387-473) - 347



Resistance between the three yellow wires is 2.1 - 2.4 (spade to spade to spade)

Resistance from each yellow wire to ground is infinite (1.0 @ 2000k ohms)



Low reading on source coil low speed means . . . ?
 

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Two quick things.



1:Make sure the small vent hole in the filler cap is not blocked.If blocked they cause a partial vacuum in the tank inhibiting the fuel flow.



2:If an inline fuel filter has been fitted make sure,if it has a direction arrow,that the arrow is the correct way round and there are NO bends or restrictions in the fuel pipes.



These are a lean-burn engine with miserly carbs and anything restricting fuel flow and you will know about it quick like leaving the petcock in the,"Off" position
 

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The low resistance from 5 to 9 (ground to low speed coil) is possibly an indication of a short in the coil. Were your checks done cold or after the bike was warmed up and showing symptoms? If not done when it was showing a problem I would warm it up until the fault occurs then shut it down and recheck the resistances. There may be an even greater abnormality then. If so the stator is bad. The yellow wire checks are OK as you know because it is charging.

Your options then are switching to an Ignitech system or replacing the G47 stator only to have the CDI fail next

Even though there is not a group buy going (from what others have posted) an Ignitech is still probably cheaper and easier than replacing a G47.



http://www.ignitech.cz/english/aindex.htm

Looks like the Sparker DC-CDI-P2 is 127 euro.
 

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Discussion Starter · #13 ·
The low resistance from 5 to 9 (ground to low speed coil) is possibly an indication of a short in the coil. Were your checks done cold or after the bike was warmed up and showing symptoms? If not done when it was showing a problem I would warm it up until the fault occurs then shut it down and recheck the resistances. There may be an even greater abnormality then. If so the stator is bad. The yellow wire checks are OK as you know because it is charging.

Your options then are switching to an Ignitech system or replacing the G47 stator only to have the CDI fail next

Even though there is not a group buy going (from what others have posted) an Ignitech is still probably cheaper and easier than replacing a G47.



http://www.ignitech.cz/english/aindex.htm

Looks like the Sparker DC-CDI-P2 is 127 euro.


I did these checks cold, I'll need to redo them while warm.



That'll make the ignitech price ~$185, plus the factory is on vacation until August 7th.



Shep, I had the tank in the sun when I drained it. I put the cap on and moved into the shady garage, you could here the vent "whistle" as it cooled and drew in air.



No inline fuel filter, I need to find one.
 

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I did these checks cold, I'll need to redo them while warm.



That'll make the ignitech price ~$185, plus the factory is on vacation until August 7th.



Shep, I had the tank in the sun when I drained it. I put the cap on and moved into the shady garage, you could here the vent "whistle" as it cooled and drew in air.



No inline fuel filter, I need to find one.
Those are European dates, translation--- 7/8/2011, so they are back in 5 days.
 

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I did these checks cold, I'll need to redo them while warm.



That'll make the ignitech price ~$185, plus the factory is on vacation until August 7th.



Shep, I had the tank in the sun when I drained it. I put the cap on and moved into the shady garage, you could here the vent "whistle" as it cooled and drew in air.



No inline fuel filter, I need to find one.
Those are European dates, translation--- 7/8/2011, so they are back in 5 days.
 

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But no VAT, so 20% less, but bigger shipping to US.


They are still a bargain compared with some modern parts.As I've stated in other posts I'd buy one if I didn't have so many good spare CDI units
 
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