Setting timing on BGM with Agusto

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Dazza
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I'm struggling to get my head round this one :?

I fitted an Agusto 6000 last year and although I wasn't overly happy how I set it up but it seemed to perform ok.

So I've just fitted my BGM, re-checked my timing using positive stop and marked up 19º BTDC.

I wound the BGM anti clockwise to its limit and strobed the timing at tickover and low revs and the timing lined up at 19º (this is the point where I come unstuck with advance -retard etc etc :) )
BUT when I increase the revs the arrow on my flywheel moves clockwise ( is this advancing or retarding?)

I always understood that the idea of the agusto is when the engine is at high revs the timing should strobe at 19º or thereabouts ( is this correct?)

So i filed the slots in the stator almost to the limit of the slots and refitted it a little further anti clockwise but this made little or no difference.

Is the way it is working now correct - have i got totally the wrong Idea about the way the agusto works? :?

Someone help me out here ..please :D
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GPMatt
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usualy you set the ignition to 24-25 static, so when it gets to about 6000rpm the timing should be 17 degrees!

this means anti clockwise (fully) on a bgm with 58/ 60mm stroke roughly should breing you close to that set up. check ur TDC mark.

;)
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Dazza
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I think I've just discovered an alarmingly embarrassing reason to my problems - so bad in fact I'm deliberating wether or not to post it....

I've marked my timing mark as 19º After TDC :oops: Feck me!

Which would make total sense as to what's been happening - Doh

I was looking at this then the penny dropped:
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paulmgreen
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might have been wise to just delete the post Dazza lol.......
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Dazza
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You could well be right Paul but others may learn from my stupidity :D
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J1MS
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Dazza wrote:You could well be right Paul but others may learn from my stupidity :D
I leant my dead stop to a mate for him to TDC a motor, and then from that point mark off 19 degrees BTDC so is could be strobed later...
A few weeks later when the scooter turned up at mine (he didn't have a strobe) to check the timing, there was no timing mark at 19 degrees BTDC, but there was one timing mark which was very neatly marked up and tippexed in to make it stand out, at 19 degrees AFTER top dead center... :roll:
So your not alone Dazza in the "wheres that timing mark gone" club... ;)
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Dazza
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So...is the photo of the disc above wrong? :shock:
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Bofs
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At first glance the disc does look a bit baffling but if you mark TDC using the red arrow then turn the disc anti-clockwise to your desired timing,lining up say 19 degrees with your TDC mark, then you use the red arrow again to the left to mark the timing BTDC.

Then with the Agusto fitted you`ll need to turn the stator further anti-clockwise,advancing the timing, you`ll find that when you strobe it the flywheel mark will show to the left of the 19 degree mark and will advance towards it the more you rev.

That`s the theory anyway, I fitted one to my SR190, it strobed ok but ran like a bucket of spanners :roll: .Gave up on it in the end :(
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Dazza
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I see..

That makes sense now,so I wasn't a total feckwit last week andI had measured BTDC not ATDC :D

I used a decent disc today as opposed to the VE effort I had before and am 100% certain of my timing marks now (although there's quite a few on the casing now) the Timing was around 24º - 25º at tickover/low revs and advanced to 19º nicely at full chat - runs lovely on the road as well.
If it aint broke.........tinker with it.....
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