Topic: its charging ok what the heck 900

[cb650 bobber]

Checked the voltages ...wrote the numbers down at home....the charging system seems to be working fine. I cleaned all the coil connections....that didnt help...checked and cleaned up the ground..that didnt help. I need to mess with the rpms it is running pretty fast didnt know if that could make it heat up to much and maybe that is part of the problem. Also I raised the Rpms because it seems to be choke heavy in the beg. even when it is warm out maybe that is pointing toward one of the multiple problems that could be causing the cold start issue.

[Laminar]

What's the problem that you're trying to solve?

[cb650 bobber]

Wont start after initial ride...Taking it that heat is an issue. Will start in about 10-15 min once it has cooled.

[TwoTired]

Jeezz, do we have to drag each little detail out of ya?  You make it so hard to help.

Does the engine not spin with the starter or spin with the starter but not fire?

[cb650 bobber]

SPins just doesnt fire....Sounds like a normal start except it doesnt fire up.

[TwoTired]

SPins just doesnt fire....Sounds like a normal start except it doesnt fire up.

I recently read in other posts that the pulser coils fail and cause this problem on the 650.

[cb650 bobber]

what is the pulser coil....just one of the standard coils

[cb650 bobber]

I am guessing getting new coils would expensive and take a while

[cb650 bobber]

and also is there upgrades to the standard coils.... I got a used pair last time...mine was cracked and would give my fits when it would rain.

[TwoTired]

what is the pulser coil....just one of the standard coils

No, the pulser coils are near the crankshaft.  These tell the spark box/units to fire the high voltage spark coils, when the crankshaft is in the proper position.
If the pulser coils fail with heat, the spark units can't make the main coils fire the spark plugs.  Pulser coils actually trigger the spark units.

You should be able to test for spark when the unit is hot.  If you have spark when cold but not (or weaker) after it gets hot, suspect the pulser coils.

[cb650 bobber]

where can i get a pulsar coil....should i just call some dealerships and see if they are stocking it.

[cb650 bobber]

Or should I do some cleanup on the connections maybe or that wouldnt help. Can I test with a volt meter.

[mlinder]

That wouldn't help. When they go south, they go south for good.

[cb650 bobber]

so if it went south for good it could still be ok when cold just not hot.

[mlinder]

so if it went south for good it could still be ok when cold just not hot.

It could exhibit normal operating characteristics while cold. Which doesn't last long in a running motor...

[cb650 bobber]

would it effect the way it runs then. Because the bike seems to run fine even for rides where the motor is def. hot. It just wont after it gets hot.

[mlinder]

Kit went through much of the same. You should read her threads.

[cb650 bobber]

I have found a lot of threads seems like everyones issues are different ...I am really thinking it may be the pulser coil. Now I have to call the dealer and see how much they want for one.

[TwoTired]

You have two pulser coils.  Each one fires a pair of cylinders.  I wouldn't replace anything until I tested it and found it bad.

[cb650 bobber]

ok how can I test those coils....I am taking it they are in the side cover on the right side of the bike....right side if you are sitting on it that is...

[TwoTired]

The pulse coils are under a cover on the right side of the bike, I think.  There should two yellow and two blue wires going there.

 The wire diagram shows these wires going to your spark units.  You can probably disconnect at the spark unit and measure the resistance of the wires and the coils from that location.  Take a cold measurement across the yellow wires, blue wires (disconnected from the spark unit). And then when it's is hot and won't start take another measurement then.  If there is a big change in resistance, you probably found the problem.

I'm assuming you have already checked for spark both when the engine is cold and when the engine is hot.  If there is no spark difference with heat, probably no need to measure the pulse coils.

[cb650 bobber]

no I havent checked the spark yet everytime I do something I am in a hurry as I watch the baby at night that is why this thread has been such a pain I have to try and find time to do things. SO last friday I cleaned up the coils changed the fuel filter and tried that ...no dice.

[cb650 bobber]

I will check the spark so I guess if I check it hot and cold and it is good then it isnt the pulser.

[cb650 bobber]

Well I didnt get to check the spark but took it around the block to see if it showed anyother signs of issues.....it misses when you hammer the throttle as well. Not sure if this would still be an issue that could point to the pulser coil