Author Topic: A10 ignition timing  (Read 3229 times)

Offline HDhikaru

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A10 ignition timing
« on: 05.07. 2008 11:08 »
 Hi
I have just spent all day today to get proper ign timing  for my  62 A10 with manual advancer
but could not start the engine.....
anyone please help!

Offline a10gf

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Re: A10 ignition timing
« Reply #1 on: 05.07. 2008 12:39 »
Hello, here are some toughts that may help. Did it start well before the timing adjustments? The engine gets petrol, and is not flooded? Sure L and R plug cables have not been swapped around? Are the points separating, and roughly within spec? The manual adj works well in moving the cam ring? Did you do the timing at full advance setting?

Check that the magneto is ok and you have good sparks on both plugs, by taking out the plugs, one at the time hold them tihgtly against some part of the engine that gives good contact and see if you get a spark. If no sparks, then try taking the plug caps off the cables, and hold the end of the cables something like 1mm from some part of the engine, you should get a good spark. Maybe good if you have someone to take care of the kicking (easy job with the plugs out) while you do the checking (and of course, carefull not to get any electric shock!).

Tell us if you got sparks or not. Good luck.

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Offline HDhikaru

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Re: A10 ignition timing
« Reply #2 on: 05.07. 2008 21:28 »

hi A10gf,
thank you for your post.
I got this bike a few month ago but never seen it  running before.
previous owner told me it was running .....

anyway,
I have healthy spark here,  point gap is 0.5mm.  cleaned up carb,
but I was checking the timing with full retard position...   maybe that was wrong...??

so what I should do is
get correct position of point with full advanced. (just before for the point to open..rgith??)
then get correct position of  piston..
please advice the best way to get this ....measure through plug hole  ???
then put the pinion gear back.

then kick with  full retard position??

Shin
 

Offline a10gf

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Re: A10 ignition timing
« Reply #3 on: 05.07. 2008 23:10 »
Hello, good that your magneto is working fine. Yes, do the adjustment with the mag's camring in max advance. Any start is best done with retard, may save your leg!

Search the forum for techniques of finding TDC and correct timing advance. Use the plug hole to find top point TDC, then back off as per spec for your A10. Even if measuring trough the plug hole may sometimes not be 101% accurate, it should be able to give you a close enough setting to start, and use, your bike.

I assume you have ok compression, ie should need a firm good kick to turn the engine properly. My quick check to know if the cylinders gets petrol is to smell for petrol vapour at the silencers. If none, try tickling the carb a little more, if very strong, likely the plugs are wet (some 'not very scientific' tips  ;) but may help in some situations).

Tell us how it goes.

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Offline snowbeard

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Re: A10 ignition timing
« Reply #4 on: 08.07. 2008 18:31 »
I used a degree wheel and a stick in the plug holes, as well as a center stop I made from a bored out spark plug with a bolt thru it.  round the end of the bolt to avoid marring the piston.  there should be a post on here giving a really solid description of how to find TDC with a stop.

I did my timing first at slack cam, which for my bike was incorrect, so I had to start over, but this time with all the covers on. 

I made a balloon to tell when my cylinder was in compression mode, rather than take off the valve covers again. I cut the tip off a rubber glove and put it over the bored out plug center stop with a small hole in the end.  when that cylinder was on it's compression stroke the finger would blow up and whistle.  then I used the stick in the hole to find TDC, set the wheel on something that turned, I think I actually used the timing gear with the magneto nut just tightened enough to hold it in place as the engine rotated, then wedged the wheel on the tach drive slot. I have the side mounted tach, hole in the timing cover set up.  If you have the tach on the inner timing cover and no hole in the outer timing cover, that outer cover's gonna have to come off, which is good because it gives you a more permanent place to "mount" the degree wheel.

on the points I used the cigarette paper to tell when they were just letting go.  put the paper in when they're closed, and when it just starts to slip out that's your spark, set it right there. 

be careful of that pinion, it slips the timing gear around as you tighten the nut, so always check a couple of times after you're done to make sure that ciggy paper releases at the right moment after everything is tight.

best of luck there, hope any of this is useful to you and not just confusing drivel. :-)
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