Rough running 914

[rhtrudder]

Still trying to figure out my engine, switch between the mags below 4000 not much drop, up in cruise, above 5000, the is a big drop on both sides, I know the ignition systems are separate from each other but is there something common to effect both 

[Red]

914 is known to have a substantial rpm drop on switching off one ignition circuit 

What are your numbers?

https://legacy.rotaxowner.com/si_tb_info/serviceinfo/si-914-034.pdf

[rhtrudder]

In the past if I have left one off I could barely notice the difference but not now , both sides the same, feels like it will cut out, I’ve never come across this information before, can drop up to 500, at 4000 , just found out the 914 runs one side a bit more advanced , I guess to help with detonation, read somewhere the earths off the cdi and coils can corrode, just cleaned them up , fly tomorrow and hope my imagination was the trouble all along 

[facthunter]

Don't test mags at high rpm and load as a general rule. Running on one does give some timing retarding effect. IF I have to complete a flight in that condition I enrichen the mixture and cruise at a lower power setting. and try to keep the head temps down..   Nev