Im not going with the degree key either. nyroc, are you going to start using high octane gas with the new CDI from now on? 92 or 93 whatever it is?

 

Dyna said to use 87.

I put 89 in because I pumped 89 into the car when I fille the 650. The car takes 87, but I knew I was going to be towing and placing a load on the motor (4 bangers aren't highly recommended for towing). I will probably keep putting 89 in the car when it tows. The car actually tows excellent on a flat, but I really do not want to tow that 650 though the mountains. I guess I could just downshift into 4th on the hills.

I think that your results next to mine proved that there is no reason to use 89 or even 93 in our 650s with the CDI. We got the same gains even though your 650 is quicker than mine.

 

87 sounds great with the CDI. I have always ran 87 octane with great results. I wasnt sure what Dynotek said though.

 

My degree key gives me 6 degrees ahead of the stock advance rate, at whatever rpm it's at. The CDI may have an abnormally high advance at an idle. Mine never kicks back.

 

The stock CDI does not fire on the first revolution when starting. I cannot remember but I think the stock unit does not fire until the third revolution when starting, The Dyna CDI fires on the first revolution when starting. That is what causes the motor kickback.

 

Good info, dadbandit. Now we need a kill switch that won't stop the starter from working so we can get the motor rolling before putting power to the coils.

 

I don't think the kickback should worry us. I honestly think that the kickback is only on the second cylinder. I only got kickback after the engine had turned 3 or 4 or so times, that is why I thought it was advance.

It would be easy to get the timing right from the first cyl, but they have to calculate the right time for the second cylinder.

funny thing, if you look at Dyna's advance chart (scroll down) you will see that the advance should be equal at idle (1100rpm) between stock and Dyna. I know for a fact that it is not equal because the Dyna CDI makes the engine idle 100 rpm faster. It can only do that with advance.

So, my question for you guys is, why is the idle advance different even though Dyna shows it the same at idle? Is the stock CDI retarding something we don't know about? Did dyna make a mistake?

Somehow, I suspect the stock CDI has the rear cylinder retarded at idle to make it start smoother due to the difficulty of predicting when to spark the second cylinder.

I'm not sure what the deal is, though.

 

Maybe the stock CDI actually has a lower advance during the startup cycle as opposed to the idle speed advance rate.

 

For the engine too kick back the CDI must be advancing the ignition timing. More ignition timing effectively creates more cylinder pressure....which makes the engine harder too turn over. Expect too replace starter related components at a higher rate.
Gary

 

That's my point: the stock CDI seems to have less advance during the startup cycle than does the Dyna CDI.