no light while static timing?

Trying to Time my 1975 xl 250,


 I have spark and the bike runs, has a brand new battery. When I kick it with the plug out it has spark, (my test light is good) but when I rotate the motor by hand and try to check the points at the wire with my test light I get no light. Grounded the light to every posible good spot o the bke, Six volt system too week to light the light?? I just want to time the thing.... and adjust the carb.... wich leads to another question...


 Does any one know the recipe for the air filter mod that doesnt effect jetting?? Thinkin about just using the stock set up and wrapping it with uni foam / hot glue / and zip tying it to the original cage inside the original box. 0.jpeg

like you said, 6v won't light your 12v test light,  might use an ohm meter.  Think emgo still has filters.

Licks, your points are not connected to the battery... your bike is a magneto ingnition run by the ignition coil in the stator and a wire to the points.  The stator coil won't make any useful current just by turning by hand.  Also, one side of the points is grounded through the stator coil and the other grounded through the spark coil so you would have to disconnect them to check with a battery and test light.


Here's a manual....



Patuca thanks for all the info so far for sure!!


 The bike actually has no skark at all now, gremlins. Cleaned the carb and was trying to adjust the air fuel mixture but couldnt get rid of the flat spot at about 3800-4200 rpms. At this point she was running ritch and hot. Did the compression test, came in at 210. (Lost fuel flow from the tank, cleaned the overflow in the bowl and regained flow.) The bike quickly started running like chit, died. Now no spark. 






I am going to look at the points, make sure I didnt fry them. Dont know how to test the coil though. Could it be something to do with the stator? Could it be a bad condensor and can it be bought seperatly, looks like the coil and condesor are package deal.


I have a wee bit of an exorsism going on here...


Any suggestions as to my next approach???

Edited by Licks

Licks, you can't adjust the carb mixture at 4000 rpm with the only changes the mixture at idle and very low rpm.  Bikes with stock jetting and carburetor  run well when the airbox and filter and exhaust are stock.   If  the exhaust or air-filter are  altered, you will have to change jets.


If the bike started running crappy after you did carb work,  that is where I'd look first if it didn't run after that.


There are only 5 items in your ignition....alternator-coil, points, condensor, spark-coil, spark plug.     First , put in a new spark plug....just to eliminate the obvious.  Then look at the points and make sure they are opening (measure the gap).  If you've already altered the timing, move it back to where it was.  


Read the manual I linked you to on how to check the timing etc.  Page 38 and 39....use a bright light and just set the timing by eye by judging when the points just start to open when at the F mark.  That will get you close.  It's all in the book,  When looking for spark it is hard to spot unless the room is dark....And, it's easy to mistake a carb problem for an ignition problem.


You have a very nice little bike, it's worth spending some time on to get it running well and they run their very best with a completely stock set-up.



Patuca, THe exuast is stock and I rapped the stock cage in the air box with coarse uni foam. I found the spark problem, it was a loose screw on the timing plate. How do i get rid of the flat spot at 3800- 4200ish and cool the running temp while leaning it out??? Raise the clip a notch? OR Start with getting a timing gun and getting it dead nuts that way?


Stoked I dont have to chase the spark !!

Got the manual Patuca thanks a ton!! If I cant get it figured with manual, I'll be blowing it up again. 


Keep ya posted...

That's good you found the problem.  Usually a bike running hot indicates a lean condition.   A rich mixture would tend to keep it cool.  I would try moving the needle one notch up or down, and testing ....if it works better in one direction  do another notch if  you have one.  Experimenting is the way.   The next time you have the carb float bowl off, check the main jet to make sure it isn't partly blocked.


See if you can get a stock filter.  The air - flow of a non-stock filter can change the fuel mixture a little too. And also the Float Level is critical,  too low and the bike will run lean, too high it's  rich.


good luck lick.



What would cuase the idle to climb and drop a little, Float level??


 Adjusted the idle, runs cooler, boggs out of the hole but still runs good up in the Rs. When I road it I stayed in the throttle,  checked the plug and it is the right color but I was up in the Rs most of the time. Not sure how to approach it now.


Fine tuning annd trouble shooting is embarassing, blowin up the post!



Hi Licks:


The first step is to take the float bowl off and check the float level...if it's not  right nothing is going to work.  While you have the float bowl off, unscrew the pilot jet and blow it out clean, and the main jet too.   When you put it together, gently screw in the mixture screw until it bottoms, then back it out 1 3/4 or 2 turns.


Check the throttle cable, and make sure the slide is not stuck and is coming all the way down easlity with the throttle closed.  Get a spray-can of WD40, and while the engine is idling spray the carb connection rubber to the engine and listen for any change in idle to check for an air-leak.  A split in the mount could leak air and change your mixture.


If all that stuff is okay it should idle and pull smooth.



Will do.

Gas flows from the petcock with the line disconnected from the carb, when I connect it, the gas stops flowing (from the petcock). Its like its not vented (overflow?). I cleaned it with a guitar string.

Im not making this stuff up. I did get it registered and plated today!

Still workin through it.

 Dropped the needle and it did not fix the issue. If I roll on the throttle it will pull through (not perfect but will pull through), If I open it wide right off Idle it bogs out still. Road it a couple miles like this and it died and ran a little more like chit. Thinkin it got a little hot.


 Im considering the advance unit might be the issue.  ??


 Any more thoughts 

Got the carb sonic tank clean idles good runs fine but Ritch.

I need to get smaller jets.

Any one know whee I can source out some new ones for the stock Kien for this bike.?

Main: 110 and 115

Pilot: 40


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