ORIGINAL: rayelljay

Binding in the main driveshaft can rob power from the overall system...you're requiring more power to fight the additional friction.
Please don't get me wrong....I am, by no means, an expert in model helicopter flight and I am only trying to "open doors" for further consideration. I'm a mechanical engineer and I build model things of interest.....I started my technical life as a jig and tool maker for a company specialising in steam turbines in 1959 and have been ensnared in that net ever since.
If you have a friend who has an identical machine, try swapping out the Tx and Rx for a tryout to see if the speed control is bad.......you could even have a gyro problem...there are a few links in that rudder control system. Is the clearance between the motor pinion and the drive gear too tight....that will sap power and load up the speed control system.
I remember one flight and the tail was a bit wild so I landed and found thatpiece of plastic tube which holds the tail rotor and gear together was a little displaced and the rotor was breaking free from its drive gear...!!!!!
Choppers...I have a question re the HBK2.
I finished a flight yestereve of just over ten minutes in around 90 deg. still air and bright sun. When I went to remove the battery it seemed a bit hot.....it's the 1500 and I think it's a 10C 'cos when I charge it, my triton shows 1.5 amp. The Pro's were fairly warm and the 400 batteries don't seem too bad but this raised my eyebrows.
Have you found a need to cut air circulation slots in the canopy to better supply cooling air to the battery area. It's got an area each side of the lower nose which could be opened up and I'm wondering whether air slots could be cut in the "windshield".
I'd be interested to hear your thoughts.....or am I being an alarmist....?
Lovely evening but 92 deg here in Kville......"but 92 deg".....???

Must begone....
Ray