Fit! D.Yeo where are ya?

[MicroHeli-Nut]

The Cybird Motor it seems is more powerful then the FEda 370.
D.Yeo I've re-timed the motor like ya said. I didn't actually adjust it to ur instruction... I couldn't find the big jump in current u were toking about, so i choose the turn with the lowest no load current draw and the least ohms... I think... Used the mulitmeter to read the 'omega' or Ohms and got the endbelll fixed at 19 "O" and 0.6~7 Amps

Fit, I switched back to the cybird motor with my modified setup. Comparison:

CYbird motor on 8 tooth.
Lift off slower ( but faster than stock Feda). Red light comes only during flares ( blasting throttle with cyclic to stabilise from a fall in height ). Flares occur as low as 3 inches above ground. Prob not enough clearance in terms of power. No loss of tail auth even with red lights on or hard flaring. ????

Feda 370 retimed on 10 tooth.
Lifts off very fast, but tail 'slips'??? Red flickers on and off and constant hover sometimes. Flaring occurs at higher height, 1m, but tail loses grip during flaring. 'Fall' rate faster, heli is more jumpy and unpredictable. ?????

Will try the Kaichin motors soon....

[MicroHeli-Nut]

Fit,
If i got me some 2 x 1200 Etecs I think the lift off would be nuts with one of the re-timed kaichin motors... or just the cybird motor on 9 tooth. DOes Daniel still carry the Etecs ? yeow_hwee u there?

[MicroHeli-Nut]

Forgot to mention, the re-timed 370 runs a bit cooler.

[Super-Hornet]

Hi all

Just wanted to add some info that I found out myself or read from other sites.

Changing pinion should not effect any change in your tail rotor. Your tail rotor changes is due to your battery cannot provide enough juice for it.

Having higher pinion Teeth count will lower the gear ratio and therefore, you have more room for your throttle BUT your main motor have to work a bit harder than lower teeth count.

Bottom line is that:
Lower teeth count = Higher Division Gear Ratio = Lesser load to Main Motor = Lesser Current Drawn by Main Motor = Main motor need to spin faster in order to give u the same amount of head spin or same lifting power

Higher teeth count = Lower Division Gear Ratio = Higher load to Main Motor = Higher Current Drawn by Main Motor = Main motor run more hotter.

Super-Hornet

[D.Yeo]

Hi Ray : Re timing a motor does make quite a difference eh...

Thing is when you set the timing where no-load current is at it's lowest you've actually set it at the motors natural neutral timing.

Like i said, as the motors as stock are actually advance timed to run in reverse, this would be quite an improvement already. But to get even more power , rotating the magnets slightly more clockwise(when looking at the motors back ) would be great.

Perhaps you could try giving it a few more degrees, say 3-5? You'd probably have an even more jumpy, powerful heli to play with haha

Hornet:

You're right about the gearing.

knowing the relationship between gear ratios and load helps you select a gear ratio that lets you bring your motors operating RPM range as close as possible to its natural optimum RPM range to let the motor produce it's best output as efficiently as possible.

[loyn]

Man you all are good....really going in depth to all the technical behind the motor....now I feed like a boy with toy (even I am in fact an old man ).

OK something for me to do now to retime my 370 and hopefully improve my heli performance and life spend of the motor. (since it will run at lower temp).

D. Yeo, just to confirm so just rotate the motor end cap clockwise until the no load current is the lowest or right before a sudden increase in current drawn right? I will try it on my spare 370 motor. BTW which shop did you manage to get the cheap replacement motor. May be I should try one of those before going for the expensive 370. Please advise and you assistant is much apppreciated.

Thanks
loyn

[D.Yeo]

loyn : Yup right before a noticeable jump is good. For me i'm too lazy to set my 300 motors properly and simply follow the ST models motor timing or around there.

just rotate the endbell till one of the four plastic dots ( the bits of the brush holders that stick out the back of the motor ) goes just past one of the metal tabs. Just follow the one i passed to you that's timed also.

If you want to try the 6.80 motor just take mine, i dont think it's worth getting another one.

[loyn]

Thanks for your advise, it is really a risk to try on those $18.5 370 motor which I may turn it into.......nothing! If you don't mind I will like to try on your motor....hopefully not to scrap it in the process... May be I can get it from you in the next funfly if there is any or even meet up over the weekend !

Really appreciate your help!

regards
loyn

[D.Yeo]

haha yeah i know, it's quite cock that whenever i get a new motor i immediately more or less disfigure the stupid thing.

No problem you can try to time either the motor i'll pass to you, or the motor i passed to you the last time, but they're both already retimed so you got to bear that in mind when you start taking current readings.

Then when you're done we could pass it to anyone else who wants to try.

I think i'll call the guy at the shop and tell him we wont be ordering, but that he might want to carry some stock and i'll tell people to get it from him.

[Super-Hornet]

Hi D.yeo.. what about Tail motor (CN12-RXC or any equivalent or better)? Any source for less than S$10 per piece?

Super-Hornet

[loyn]

Ok in that case I will try to work on your old motor (the one you pass to me other time) instead of getting another one from you. As I though the other one has not been timed yet. So I can start new!

Anyway thanks again will keep up update on my learning.

As for the tail motor, I want to try the coreless motor with 5:1 gear ratio. Not too sure will work anyway!

[D.Yeo]

loyn you should also take the new one and try and see if it's powerful enough for you.

[loyn]

D, Yeo, OK then I will work on the new motor instead of the old one....BTW what do you mean by using 2 cells to test for no load current. 2X 1.5V battery or 2P lipo 8.4V, please advise

[D.Yeo]

Loyn : sorry meant 2 1.2 or 1.5 cells not lithium heh

[loyn]

Thanks that mean 2.4~3V, that is great as I can use my home build power supply which come with amp and volt meter to do the timing. Hopefully it is not more than an amp that is the limit of the power supply.

Will update you the outcome, Thanks alot for the information.