RCU Forums - View Single Post - Saito FG-60R3
Thread: Saito FG-60R3
View Single Post
Old 11-10-2018, 09:58 PM
  #1874  
cathurga
 
Join Date: Jan 2007
Location: Dubai, UNITED ARAB EMIRATES
Posts: 500
Likes: 0
Received 2 Likes on 2 Posts
Default

Adrien,

Thanks for contributing, I am sure you know more about these ignitions than most of us combined, so its good to have you here.
I understand the way the timing works, and with a history ot timing older car engines (before electronic ignitions) it was always interesting to see how the advance/retard setup worked on the vacuum of the engine. All you had to do was remove the distributor cap, and suck on the vacuum tube, and you could see how the entire "points" chassis would revolve around, thus advancing when the revs increase. The exact same thing is happening with these ignition modules, except it is being done electronically, based on the engines speed, at any given point.
I imagine that if there was a spark ONLY at 28 deg while you were starting the engine, there would be many sore hands from the engine kicking back, and not a lot of running engines, so having the spark "retard" to around 5deg BTDC, or even on BTDC makes sense when starting. At 6000rpm, the fuel needs time to burn properly, so the spark is advanced.

The problem that I am seeing, is that it is physically impossible to move the sensor to a point where it is able to be timed at 28Deg....there is no movement of the hall sensor to do this.

Its a shame you dont have one of these engines to check it out on. Unfortunately, being in Dubai, it doesnt make sense for me to send one of mine to you.

In my video above, I mentioned that I have a second FG60, and although I havent posted the video here, I did a check with that engine, and it is exactly the same. If there is any difference in the timing, it is very small. The sensor is in the stock position, and at the point, the magnet comes into contact with the hall sensor at around 45-48Deg BTDC. Thats a long way off.....

I also wish that Saito or RCexel could see and take part in this discussion, if nothing else, just to justify what each other is saying. Its a lot of money to be spending on model engines, and would be nice to know WHY they have done it the way they have. Its quite obviouls that they are trying to correct things in design of these engines... They have adopted the Ray English mod of the brass bushing, the intake variances since they were released, and more recently, the piston design has been changed to lower the compression. Most of the failures of these engines has been cylinder mounting failure....and what causes this.....? High compression? Hydrolock? Excessive heat?...or maybe...pre-ignition....cos' pre-igntion is most definately a symptom of timing problems.....

Anyway....