Heliguy Forum - RC heli forum

I decided build a plastic Belt CP from spare parts I had from an old kit. I have the original rate gyro, receiver and radio so ordered a new ESC and motor. Here is the motor I ordered. The 25a ESC also from this place.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=5245

The motor only has a 3500 KV rating and I don't know how powerful it is compared to the Belt CP stock motor, but I fitted it with a 13t pinion (which is all I had at the time) and setup the heli.

The rudder was moving in the right direction and the gyro direction was correct. THe problem is when it's just about to take off it wants to spin really fast in one direction. When I normally setup a heli I move the tail server forwards or backwards until the tail is stable. I tried this but it seems very sensitive and I can't find the stable point. For example, if it's spinning fast clockwise I move the server back towards the tail but then it spinds fast anti-clockwise. I don't seem to be able to find the right point.

Here is my concern. I have introduced a motor that with the 13t pinion could be much more powerful that the Belt CP stock motor. The only thing that occurred to me was the blade padles. Do I need to get bigger paddles with more head speed? I would have guess not because the tail is also spinning faster if the head does. But other than a faulty gyro I have no idea what could be wrong.

Any ideas much appreciated. Thanks.
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