Ignition Checks at Various RPMs?

[DHeal]

Occasionally I would like to verify the independent operation of each of the ignition modules on my 912 ULS at times and RPMs other than during the usual 4,000 RPM run-up. Is there any danger to the engine if I perform an ignition check at 2,000 RPM?, 3,000 RPM?, 5,500 RPM?, etc?

I know that an after-fire event in the exhaust system is typically a concern on some engines if too much unburned fuel is introduced into the exhaust system following an ignition check at high RPMs. Any concern here for the 912 ULS?

Thanks -- David

 

[Piper J3]

I check ignitions often while flying especially if flight plan takes me over water. Simply shut off one ignition at a time and look for RPM drop. Goes without saying to be careful not to shut off both ignitions otherwise you'll be flying a glider...

 

[RFSchaller]

From the ROTAX course it appears the only think special about4000 RPM is to be at a high enough RPM where carb imbalance is not a issue for rough running.