timing help needed...

chopit25

chopit25

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Ok so i have read alot here on this and went by the manual and even watched some youtube videos. I amlost now though. Every wire and connections ir correct, grounded well and new. Carbs are clean as new and set to factory settings. Brand new coils, points, condenser. I tried to start the bike and it seemed the timing must have been off so i checked the cam chain adjustment and it was in spec. I adjusted the valves to the manual specs. I have never had it run so i tried the static timing method by using a 12v bulb on the right point and turning the crank with a ratchet. When i spin it around it lights up way after the timing plate and no matter which way i rotate the points plate it doesnt even come close. Then the coils got really hot and shut down. I hope i didnt fry them before ever even getting it started!
It is a 73 tx650 with stock points setup. Am i missing something or could i have done something wrong when adjusting the valves? They were just too tight so i backed them out to the manual specs.
Any help or suggestions are greatly appreciated! :wtf:
 
Hey, chopit25, having fun? Remember this?

chopit25 said:
... I am sure the PO was retarded. I swear everything on this bike was screwed by the PO ...
Click to expand...

If the points are way off, and the points plate can't be adjusted enough to get static timing close, then maybe it's time to check the cam timing. Quick check is to see if the cam/mechadvance indexing pin, on right side of head, is perfectly vertical (top or bottom) when at TDC. If not, may have a severely stretched camchain, or worse, a cam out-of-time.

If the cam is in time, then check for proper assembly of the mechanical advance, advance rod and pins, and points cam and it's pin. Wouldn't hurt to disassemble all that anyway, for good cleaning and lube. It's possible to find missing pins, backwards mounted slotted advance rotor, worn weight activation ears, damaged receiver slot in advance main plate, or simply a worn-out points cam (lubrication neglect).
 
chopit25,

Just be sure that you do not have the points wired to the wrong cylinder, or the pins in the advance rod out 180 degrees. Check this little detail as well:

atu7.jpg
 
TwoManyXS1Bs said:
Hey, chopit25, having fun? Remember this?



If the points are way off, and the points plate can't be adjusted enough to get static timing close, then maybe it's time to check the cam timing. Quick check is to see if the cam/mechadvance indexing pin, on right side of head, is perfectly vertical (top or bottom) when at TDC. If not, may have a severely stretched camchain, or worse, a cam out-of-time.

If the cam is in time, then check for proper assembly of the mechanical advance, advance rod and pins, and points cam and it's pin. Wouldn't hurt to disassemble all that anyway, for good cleaning and lube. It's possible to find missing pins, backwards mounted slotted advance rotor, worn weight activation ears, damaged receiver slot in advance main plate, or simply a worn-out points cam (lubrication neglect).
Click to expand...

Twomany, so does this mean i need to tear into the top end? I think i will take the advance to clean and inspect. Can you lube with just multipurpose grease? The last time i actually got into an engine was in high school to redo a go cart engine and i had an instructor so i have been nervous about getting in too deep on my own.
Oh and yeah i am having tons of fun! Lol
 
pamcopete said:
chopit25,

Just be sure that you do not have the points wired to the wrong cylinder, or the pins in the advance rod out 180 degrees. Check this little detail as well:

atu7.jpg
Click to expand...

Pete, i checked and the lines on the advance line up. I checked the wires and from what i can tell the right coil is wired to the right side point and vise versa. I have one power lead to the two coils on the yellow wires, two black wires come out of coils to condenser and points, right coil black wire goes to a double bullet connecter which is right point and one condenser lead together and same on the other side.
I am stumped and dont want to jump the gun and just tear into things and mke it worse. I will check the advance unit closer to see if something is out of whack.
 
The top set of points should be hooked to the right coil/cylinder, the bottom set to the left. I think your advance rod is assembled correctly since the scribed lines look right but I guess it's worth checking. Do you see that little slot showing from behind the nut in Pete's pic about at the 10 o'clock position? That's the slot for the locating pin. The little points cam on the other end of the rod will have a similar slot and pin. They both need to be facing in the same direction .....

AdvanceRod.jpg


It's possible to assemble the rod with one of the pins 180° off from the other in which case the timing will be 180° off.
 
chopit25 said:
Ok so i have read alot here on this and went by the manual and even watched some youtube videos. I amlost now though. Every wire and connections ir correct, grounded well and new. Carbs are clean as new and set to factory settings. Brand new coils, points, condenser. I tried to start the bike and it seemed the timing must have been off so i checked the cam chain adjustment and it was in spec. I adjusted the valves to the manual specs. I have never had it run so i tried the static timing method by using a 12v bulb on the right point and turning the crank with a ratchet. When i spin it around it lights up way after the timing plate and no matter which way i rotate the points plate it doesnt even come close. Then the coils got really hot and shut down. I hope i didnt fry them before ever even getting it started!
It is a 73 tx650 with stock points setup. Am i missing something or could i have done something wrong when adjusting the valves? They were just too tight so i backed them out to the manual specs.
Any help or suggestions are greatly appreciated! :wtf:
Click to expand...

Have you set the points gap to 0.014"?
 
Does the advance rod just slide out or is it hooked to something that turns it? Sorry not at home so imagining all the worst case scenarios. Lol
 
Remove the nut and little disc from the advance side and slide the rod out the points side with the points cam still attached. You may need to spread the points sets open a bit to get the cam and rod to slide past them. But to check the alignment of the pins, you don't really need to remove the rod. The pin slot on the points side is usually more covered with the nut and may be hard to see unless you remove that nut.
 
So why are the coils getting hot? If it is just out of time, the system is still operating properly, just firing the plugs at the wrong time. The coils getting hot would seem to indicate a different issue, no?
 
I figured they were hot because I had the ignition on for a long time while I was trying to find the right firing/timing with no air flow. Wouldnt they get hot after a long time with no air flow and power going to them? I thought the coils were always hot with power and the points create a ground which causes the spark. Is this wrong?
 
The coils build up a charge (and heat up) when the points are closed, release it when they open. When running, this cycle constantly repeats itself so the coils aren't allowed to charge (or heat up) for too long. When you're static timing the ignition with the motor off, this may not happen. A coil may sit there with its points set closed and just keep charging and charging, getting hotter and hotter. That's why it's best to turn the key off while you're doing all your setting and adjusting, and just turn it on for a short time to do the check with the light bulb. Then turn it off again while you make any more needed adjustments.
 
Cool that's what I thought. I wont just leave the key on anymore.
Thanks 5twins for confirming what I thought.
 
If the advance rod assembly is correct, be sure to check that 3rd locating pin for the advance unit that Pete pointed out in post #11. That pin locks the advance to the cam "in time" and your timing could be anywhere without it.
 
I think you misunderstand how points ignitions work.
As the engine turns the points open and close. When the points are closed power flows through the coil, this creates a strong magnetic field around the coil.
When the points open the power stops flowing and this magnetic field collapses and creates the voltage in the secondary windings of the coil producing the voltage to jump the gap at the plug.
With your light bulb hooked up it will only light up when the points are open. This means as the engine turns and comes up to the marks the bulb should light up as the marks line up. Not go off. The points close about 90 to 100 degrees before they open. When they close makes little difference to timing, it's when they open.
So set the timing marks to line up between the fire marks. Now turn the key on and the engine stop switch. Turn the backing plate till the lights off, then turn it back a bit till the light just come on.
It can take a bit of trial and error to get right. Do this on the upper, right set first, then repeat for the lower left set.
The repair manual explains this very well.
I use my ohm meter for this. That way you don't risk hurting the coils. Just unhook the points wire to the coil, attach this to one lead of your meter, hook the other lead to ground. Now when the points are closed the meter will read very low ohms, as they open the reading goes to infinite.
Leo
 
Ok I got it now. I was doing something wrong and decided to just start over today with the manual and multimeter. Fired right up first kick! Fuck yeah!!!
Thanks for the help guys!
Now I gotta figure out the carbs because it starts with one kick every time but the idle is really high. I will do some reading and start a new thread if need be on that issue. I am stoked!!!
 

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