newbie, overheating engine

[Helinovice]

Hi,

my name is Michel De Meyer, living in Belgium, started with dragonfly 4 about a year ago, moved on to nitro (Kyosho Caliber 30), starting to fly 8 figures by now, not so spectacular I know.

I recently bought another electric heli, carboon 400(zoom/shogun style), don't know if it's a known model in the U.S., came with servo's and brushed motor, but I seem to have problems with it. After +/- 3min engine is HOTHOTHOTHOT (burned my fingertips)

motor slows down, measured the lipo pack, voltage still 11,35V.

Is this normal? Is there a solution besides going to brushless?

regards,
mike

[sportygreg]

Make sure gear mesh isn't too tight and belt tension isn't too tight-anything putting extra strain on the motor will heat it up.Consider getting a heat sink for the motor-only $4-5 for a decent one.A smaller pinion will reduce head speed but motor will run cooler and too much pitch also bogs motor and causes heat problems.

[Helinovice]

Many thanks sportygreg,

will check the gear mesh if it isn't too tight.
I have another question though, is it possible that engine heats up so much that it continues running but hasn't got power enough too lift the heli? I'm still in the "non spectacular flying zone", so I guess pitch is ok. My pitch curve is 0° at low sitck and about 8° at full stick, engine is also 0 at lowstick and full at high stick, both graph's are linear.

Was stupid before and threw away battery packs(lipo), cos I thought I wrongly charged them(not familiar with electronics ). Now started measuring them, batteries are not the cause apparently.

apologies for newbie question, if I should be in a different forum, please tell me

Gracias merci bedankt

[sportygreg]

Well,pitch is not your problem-motor should not get hot enough to burn your fingers.An inefficient motor wastes energy as heat and the brushes are literally burning up-you should also see if the ESC is getting hot which would indicate the motor is drawing too much juice.A hot motor will slow down because resistance increases and bushings or bearings are being galled because lubricant is cooking off.If you can't find any obvious reason you may just have a motor that is not adequate or of poor quality.

[Helinovice]

Hi again,

thanks for all your advices, I contacted the manufacturer about the motor, he admits the motor is just enough to do some transition flights for a short time. So I guess all I can do is switch to brushless motor.

Does somebody has any advice on this, will I do with a 15A speed controller?

many spanks,

greetz

Michel

[BLACKHAWK DOWN]

id go with 25A or 30A esc just incase ne thing happens u have security especially if u wanna use differntyt and higher mah readings for ur batterie u dont have to change esc everytime.

[Helinovice]

Thanks guys,

upgraded to brushless 3200kV with 30A ESC.

Heli flies very nice and have flight times of about 14 min with 1800mA lipo,

I guess this is not too bad isn't ist.

happy landings