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Ok Joe, your stator is identical to mine, nothing fishy there.
The reason for asking, is I just cannot figure out why you only get 24,5 mechanical advance, while I get 29.
Twisting both base plate (base plate alone should give more or less 25-21 range timing) and pick ups should give a lot more advance than 24,5.
Now, let us go through this step by step. Don't remember what I and others have written elsewhere about this, just stick to the following:
1: Find the 3,13mm (23 degrees) value, and be 100% sure you are correct. (If not, everything else will be uncorrect later on in the process)
2: When found the 3,13mm distance poston crown to TDC (you gotta use the special measuring tool you actually screw down in the plug threads, all other methods could give you false readings), make a exact mark on your rotor with your marking pin set spot on to it. Make sure you look from the exact same angel every time you look at it.
3: Now you know at what point your stroboscope is supposed to hit when you KNOW you hav e 23 degrees advance.
4: Use the flat curve on your zeel, and set it to 23 degrees.
5: Fire it up and let engine warm up.
6:When engine runs smooth at idle, use your stroboscope and see where your 23 degree mark on the rotor you just made by using the special tool finding the 23 degree value by reading off 3.13mm distance piston crown to TDC, is compared to the pin you sat exactly at the rotor mark at 23 degree.
7: You alreadu have the static timing set at 24,5 degrees on your zeel, and hopefully your just set 23 degrees timing mark is way off. Now, while engine is running, set the static angle on zeel until you are spot on with your 23 degree mark and pin. You will see that changing the static angle value on zeel, also change the position on the 23 degree rotor mark you just made, com pared to the pin.
8: Set the static value on zeel so you match your mark/pin spot on. When spot on, the static angle you now have on your zeel to get it spot on, is your mechanical timing on engine. Mechanical timing equals to static timing, and that value is the max advance you can get.
9: If your 3.13mm measurement is dead on, and your 23 degree mark you made based on the 3.13mm measurement is dead on to the pin and you read the the stroboscope timing to the mark/pin spot on, hopefully you have ended up with a 27-30 static angle value on your zeel.
10: Thing is, lets say you ends up with 28,5 degrees static/mechanical on your zeel, and in real world plot in 24,5 degrees, you ar 4 degrees off all the time from the timing curve you have put in. That is a huge difference.
11: Use your new 23 degree flat curve, and take it for a ride.
12: Then, use my curve provided for you and take it for a ride:
1. 900 rpm 21 degrees
2.1300 22
3.1600 24
4. 5500 28 (or max advance you can get, same as static angle put in, but stick to 28 degrees, not more advanced than that)
5. 6000 24
6.7000 23
7.8000 22
8 8800 19
This is my actual curve, and it works really good on my bike.
Basic theory: You need the most advance you can get in the 2/3 rpm of max torque rpm, or at the time returning wave enters cylinder just before piston close transfers.
But you gain from advance from all the time transfers are open when that supercharging pulse arrives. That pulse can be very hard, and supercharge as much as 1 bar or even more at race engines.
All 2-strokes are affected by this phenomenon, the torque dip.
You have 2 additional holes cut into your cylinder, the rear boosts ports. Just below those tunnels you have a single petal reed almost kissing you piston. This reed is affected by the returning wave, and creates a even greater torque dip than if the reeds were placed further away from cylinder, or for a piston port. And you feel it better, as you have more power in the 2000-4500 rpm area than if piston ported. And the crisp throttle response you have in that rpm area due to the reeds when everything is dialed in, you loose some of it in that critical time just before piston closes transfers. After they are closed (when wave arrives) you are in the powerband and everything changes as you do not have a pumping engine anymore, but have true resonance that runs your show.
The whole point in advancing as much as you can in that critical time, is that the returning pulse gets weaker the more advance you have. Thus, it messes up less if you advance the timing.
Good luck
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72 H2, 72 H1B, 74 H2, 74 H2 Cafê Racer, 71 F8 Bison
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............he is the one that clued me in on the needle jet being the lower portion and the needle being the upper portion..........then I did my due diligence and found the chart showing the relationship between needle jet and needle in the VM super tuning manual...........just as he expalined to me.........and on the needle between shifts at 3/4 throttle and listen for the "ping" when backing off the throttle between shifts.........I heard it, plain as day.........then richened the needle up a half notch (using a 5/20 shim kit)........I kept all his PM's for future reference.........he knows what he is talking about......thank you Scott............it's crisp and clean now
