How many degrees should be between the TDC and the magnet attached to the timing ring of this engine?

On an engine with a CH ignition you use the degree wheel to set things correctly. You time the actual spark not the magnet.

I checked this angle using a protractor; translated the position of the magnet using a needle saw, then projecting this point and the TDC to the intersection on the spinning backplate as follows, is this a valid way to measure it? most important is the angle shown on one of the pictures correct for this engine?:

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Terry, what is the correct degree that your ignition should fire at with the BME 110?
Thanx
Ralph

TKG
I see what you mean. I used to do the tune up of my Bug VW, by then I adjusted the spark using a strobe light gun. The CH electronic ignition will automatically sens that the engine is accelerating and will advance the spark accordingly.
However the magnet still will be adjusted in the factory or at field if that ever, ever is necessary.
I just want to make sure what I have is OK, since this morning I tried to fire up this engine for the first time. It kicked-back on me, possible flooded carburetor or bad hand start technique, I waited and tried again with same results. It was too late decided to go home and try again next weekend.

To date, I have never had a kick-back on my BME 110, or any other auto adv. electronic ign. engine. I have had my 110 flooded and still nothing happened. I do flip my props pretty vigorously and fast though.
I would e-mail Keith Monday and see what he recommends. That engine should not kick you.

I had that happen to me on a brison 2.4
The engine was flooded to the point that the plug was soaking in fuel.
I removed the plug, a few flips to clean it out then started on the 3rd flip.

Basic set timing should be around 28 deg BTDC

The quickest way I know to get an engine to kick back when you start it is to have the throttle all the way open. That'll work to bust you up almost every time. Leave the throttle closed and only open the throttle trim for starting. Choke or no choke. Flooding the engine is the second quickest way to get a kick back.

You can download all the timing proceedures for a CH ignition, along with a copy of the timing wheel, at the CH website.

By using the method explained in the CH web site, the meassured timing angle was be 27 +/- 1 degrees. The spark must be the actual indicative to measure the ignition timing angle. The angular position of the magnet with regards to the TDC can't be used to specify the ignition timing. The ignition timing angle is definitely affected by the magnet angular position, however there must be other factors to consider that will impact the time when the spark occurs, such as: the gap between the magnet and the sensor hall, the internal delay introduced by the electronic circuits .The hall sensor triggers the electronics inside the ignition, however after certain time the actual spark is generated, hence the difference in my readings ( 36 vs 27 degrees).
By the way, thanks to tkg, RTK and Keith.
So now I am confident about the timing, next think to consider: I need to review the hand start technique that I am using.
If you have a good hand start sequence for this engine, let me know. Another reason why I want to rule out any possible issues is that those kick-baks really hurt, in my case the effects were felt in my elbow, which by the way now is feeling better.

The hall effect switch triggers the ignition when the magnet leaves. It does not fire center line to center line.
Strength of the magnet, air gap and sensitivity of the sensor all effect timing. This is why we say to time the spark and not the parts.

This is how I start all my engines Albatross

Choke on, Ignition on, Throttle set for high idle
Flip till it pops once then stop, do not continue flipping
Choke off, Throttle at idle or 1 click higher
1-3 flips and it is running.

This is how I start my BME.
Choke on, Ignition off, Throttle set at idle
Turn prop over by hand 6 times.
Choke off, Ignition on, Throttle set at idle
It starts on the first flip 80% of the time.
Always start by the 3rd flip

Make sens to me, your method is similar to what others have described to me. By performing the the two steps described at the beginning of this sequence, I will know that the fuel already arrived to the ignition chamber and most important the right or near the optimal amount of fuel to allow the engine to start.

This is what I do to start with my ZDZ 50:

Choke On, Ignition off, full throttle.
Flip prop, paying attention to the noise of the engine/exhaust, hard to describe in words when it changes, then I know that the fuel is in the ignition chamber (takes around 15 flips), at this point stop flipping.
Ignition on, high idle
it fires at right after one flip.

I used pretty much the same method with my BME 44, which by the way was hard to start.

That afternoon I tried to apply this approach, since I am not used to the engine/exhaust noises, the only way for me to tell that I already have fuel at the engine was by looking at fuel line at the carburetor end. Harder to apply when the cowl has been already installed.

I will try that next time.

Thanks again.

I crank my BME:

Throttle on idle, choke on, igntion on, flip till starts and dies.
Choke off, flip till runs.

Hello F1racer- How are you liking that BME? Pretty nice aren't they.

Yes, I finally moved up to 35% planes and the BME 110. I could kick myself for not making the move before now.
I ran about 3 gallons of fuel very rich with a 26 X 10 NX, then went to leaning it out, within a couple of more tanks the 26 X 10 was ripping. I am now flying a 28 X 10 NX on a WildHare 35% Extra.
I am really liking this combo.........
It's like flying a kite.
This engine is really a stump puller.

If you like the NX, you a Beila or a Menz on it and you will fall in love all over again!