Blueadventures

Maybe phone flexible Drive and ask if they have same compond grade in your sizing.

Lord Mounts Part No. CB220113 from Flexible Drive are the same size and used over here; I am told by another Skyranger owner in Australia. However I purchase from the manufacturer.

These are the Skyranger ones. 13 pound a set at Flylight Airsport UK. (Image apart is the ones I replaced on a Skyranger last year.)

Hearing that an instructor is involved it's interesting that he has not provided advice and connection to an engine service person. Seems the instructor is leaving it up to the owner to sort the engine issue and is prepared to run a time expired engine with unknown maintenance history. A very good instructor would not do such in my experience as they would ensure the aircraft is airworthy and if asked provide advice on required work before operation of the aircraft.

Best to phone RAA with aircraft details and they will advise if required for its category and send the documents and the form to be completed by an L2, annual requirement re engine condition report etc. (I have done a couple.)

MARAP Engine Condition report #23 and can't be used for training or hire.

If your not solo; I would not be doing high speed taxi runs as you will be in the air before you know it. Wal is great to talk to; a full carb rebuild by him is a good option to set up for trouble free operations into the future; especially if it has not been done for a while and the needle, o rings etc and worn a perished. I'll PM my contact should you wish to call. Cheers.

Give Floods a call and they may be able to solve the issue and comment of fast throttle movements. The POH for the Gazelle will state throttle operation method recommended on take off and other situations. How many hours have you done with this engine or other 912 Rotax?

Are you moving from idle to full throttle over a four second period? The Rotax does not like fast throttle (like it sounds when you refer to "stab the throttle quickly") which is not correct application of throttle according to Rotax.

Worth dropping off the carb bowls and check closely to see if any slithers of fuel hose is present (you said fuel lines replaced) while off check the floats (type and weights). Next I would do a mechanical balance as per the maintenance manual. Then watch the movement of the throttle arms through the travel. Then run engine up again; if vibration still present and same and when in the vibration rpm range pull the carb heat and note what occurs. Cheers and I have some other checks but do these first.

DPP is a bit lacking at times in my past experience.

Never been an issue to post relevant links to information aviation relevant. Thanks for info. Cheers.

Do you need to recheck its configuration? Just a guess. Cheers.

Best that you read the moments on the aircrafts w&b sheet; it will show the info about the seats and the fuel tank behind and the effects of differing mass weight at those positions. It's important to know. Cheers.