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"An engine with a spark timed about right will usually fire if there's gasoline in the combustion chamber."

This is why I'm saying something other than the carb is hosed up at this point. Valve lash to tight... leaky rings.... etc.

110lbs you should at least get a little running on starting fluid. NOTHING tells me (if there's some compression) that you have to check the STATIC timing.

Find TDC on the compression stroke and see where your points are opening ref that. The points advance and cam are on a tapered NON-keyed shaft. It can slip. Rough static timing is done by knocking that whole assembly loose and replacing it loose with the piston at some (I don't have my book with me) position either at TDC or just before. The advance is turned till the points just open (with the advance plate centered in it's adjustment slots).

I'm doing this from memory so someone feel free to fill in the details.

While you are at it, check that your battery is ok and all the associated wiring. You can manipulate the points with a grounded plug and should be able to make it spark.

Poor mans leak down test could tell you about the compression situation. Put the Piston at TDC (again, on compression) and push your rubber tipped air blower against the plug hole (if you have one of those compression testers with the gauge that is on a quick disconnect... guess what ... that will usually chuck right to your air line). Dial the regulator down LOW and feed in some air. Listen at the intake, exhaust and breather. Where's the air going the most... out the intake you have a sticky intake valve etc.

TG

Last edited by tg4360; 03/21/16 6:22 pm.

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Ok. Still working thru this

Please correct me if I have this wrong

My inner lifter should go to my exhaust push rod and my outer lifter should go to my intake push rod.

If that is opposite my timing is 180 degrees off?

Thanks

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Tim:
is there any chance you can borrow (just for a try) a carb with all the cables ect of a bike thats known to be running fine .........if your bike starts and goes ok you will know for sure its a carb problem, if it still doesnt go its not the carb.

no one has mentioned fuel height in the bowl yet .......that can have a huge effect on keeping it running


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So my inner pushrod should go to my exhaust valve. But if my inner push rod goes to my inlet value instead of my exhaust will my timing be off 180 degrees "?
Thx

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If you get them the wrong way round it will not be out by 180 but the valve timing will be totaly wrong with the inlet valve acting as the exhaust and visa versa, the spark does not change. To get the timing out by 180 you just pick the wrong TDC so thespark is 180 out as its a 4 stroke not a 2 stoke.

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Get a chop stick and feel the piston rise then fall on the intake stroke then when it hits the chop stick before tdc just get it to top, set points at cut out square on cam, push it with screwdriver to advance atc springs so points just start opening, put in plug flood and kick. then you can strobe or whatever. Make sure your points plate is in middle of adjustment. If it starts there then you have enough room to advance or retard it by moving it sub mm steps. You can watch tappets to know what stroke your on when using a probe. Don't stick in the stick too far it can get jammed on opposite side of bore.
S


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