Tuned 395xp - ignition timing

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Time for a bit of an update after running the saw today. This is first run since crank seal replacement and frigging with ignition timing after shearing the flywheel key (weather and access to field).

Things I've learnt:

Coil is unlimited as far as I can tell,  I saw 13250pm on the tacho once while settting the high speed.

Coil has no spark advance curve, constant tIming above idle speed.

Piston stop method of finding TDC gave me exactly the same result as using a piece of wire in the exhaust port - but it is simpler, less juggling.

 

Sadly I didn't get to check ignition timing before stripping the key out the flywheel. My best estimate of standard ignition timing is 19 degs BTDC.

I've advanced timing to  25 degs BTDC, engine seems quite happy,  no nasty noises or signs of impending doom. It has had 4 tanks through it today whilst milling oak, 28" bar with 22.5" max cut, (need longer bar...). Engine runs pretty strong, I'd like to think a little stronger than before but no hard evidence to support this.

Starting is more precarious,  starter rope was ripped from my hands half a dozen times; it doesnt seem quite as willing to start.

 

And that's about it,  I'll stick with the 25 degs of advance for now, the starting issues being the limiting factor for me. 

[spudulike]

When I get a 395 in I will do my patent method of getting the timing right and send you a pic along with the method of getting there. Just getting a shed load of 365XP Xtorqs in at the moment for conversion...and a brand new MK2 550XP.

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26 minutes ago, spudulike said:

When I get a 395 in I will do my patent method of getting the timing right and send you a pic along with the method of getting there. Just getting a shed load of 365XP Xtorqs in at the moment for conversion...and a brand new MK2 550XP.

That would be very much appreciated, hopefully it'll confirm where I'm at. ...

Clean machine eh, someone's spoiling you !

 

Thank you mister.

 

[spudulike]

For a change, a brand new 550XP and 365XP plus another very clean 365XP. Makes a nice change!