SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Jul 29, 2013, 08:10 AM
Registered User
Australia, VIC, Frankston
Joined Jun 2013
28 Posts
Discussion
Yak 55 power plant

I purchase a Hobbyking Yak 55 3d plane,

http://hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=17521&rc=(<strong>248</strong> replies)-(<strong>80</strong> comments)

I installed a 480 size motor 960kv from out of a Parkzone Mustang which I thought would work well, and fitted an 11x7 prop with a 1300mah 3s battery and a 50amp hawk speed controller, on full throttle the plane wouldn't pull out of my hand when held verticle, do I need a bigger motor? change to 4s ?
natwill is offline Find More Posts by natwill
Reply With Quote
Sign up now
to remove ads between posts
Old Jul 29, 2013, 08:28 AM
Registered user
Joined Oct 2011
109 Posts
I believe they make different Kv's in that size, that's the wrong kv, too low.
Ryan1325 is offline Find More Posts by Ryan1325
Reply With Quote
Old Jul 29, 2013, 08:34 AM
Registered User
Australia, VIC, Frankston
Joined Jun 2013
28 Posts
yak 3d

OK...thanks for that, they have a 1300kv motor of a similar size that I will order and hopefully that will do the trick
natwill is offline Find More Posts by natwill
Reply With Quote
Old Jul 29, 2013, 07:43 PM
Shore Huckin'
KE Spin's Avatar
Ohio
Joined Aug 2010
2,693 Posts
Hold on for a minute guys.

The 480 motor with an 11 x 7 prop should have plenty of power. Let's slow down and look at a couple of things first.

It sounds like the lack of power is likely due to a weak battery. To diagnose if the problem is the battery or not could you answer the following:

1. Is the battery fully charged (should be around 12.6 volts when fully charged)
2. How old is the battery
3. How many cycles are on the battery
4. What is the discharge "C" rating of the battery
5. Have you balance charged the battery
6. Do you know the individual voltage of each cell (the cells should be at 4.2 volts +/- .05volts per cell at full charge)

Note: A very standard prop for a 480 size brushless motor is an 11 x 5.5 apc thin electric. The 11 x 7 is higher pitch and will eat your battery power quicker. You may actually find out that an 11 x 4.7 apc slow flyer prop may work better and give you longer flight times as well.
KE Spin is offline Find More Posts by KE Spin
Reply With Quote
Old Jul 29, 2013, 08:17 PM
Registered User
RCstudent's Avatar
United States, WA, Bellevue
Joined Jan 2013
283 Posts
I personally used the turnigy l3010B-1300kv. It has amazing power, unlimited vertical... I believe Michael Wargo uses the same motor in his videos. For 15$ it's a must have!! I have a 10x4.7 prop, 50a hk esc, 3s 1600mah nano-tech
RCstudent is offline Find More Posts by RCstudent
Reply With Quote
Old Jul 30, 2013, 07:38 AM
Registered User
Australia, VIC, Frankston
Joined Jun 2013
28 Posts
thanks for that I have just ordered the 3010b 1300kv motor, should I down size prop to 10 x 4.5
natwill is offline Find More Posts by natwill
Reply With Quote
Old Jul 30, 2013, 07:41 AM
Registered User
Australia, VIC, Frankston
Joined Jun 2013
28 Posts
Quote:
Originally Posted by KE Spin View Post
Hold on for a minute guys.

The 480 motor with an 11 x 7 prop should have plenty of power. Let's slow down and look at a couple of things first.

It sounds like the lack of power is likely due to a weak battery. To diagnose if the problem is the battery or not could you answer the following:

1. Is the battery fully charged (should be around 12.6 volts when fully charged)
2. How old is the battery
3. How many cycles are on the battery
4. What is the discharge "C" rating of the battery
5. Have you balance charged the battery
6. Do you know the individual voltage of each cell (the cells should be at 4.2 volts +/- .05volts per cell at full charge)

Note: A very standard prop for a 480 size brushless motor is an 11 x 5.5 apc thin electric. The 11 x 7 is higher pitch and will eat your battery power quicker. You may actually find out that an 11 x 4.7 apc slow flyer prop may work better and give you longer flight times as well.
Thanks for your reply, the battery seems ok from testing on the watt meter, admittedly it had about 60% but I thought that this shouldn't matter, I have ordered a higher kv motor, hopefully a few more rpms will do the trick
natwill is offline Find More Posts by natwill
Reply With Quote
Old Jul 30, 2013, 08:43 AM
Registered User
SubaruMike's Avatar
United States, DE, Magnolia
Joined Nov 2011
389 Posts
Quote:
Originally Posted by natwill View Post
thanks for that I have just ordered the 3010b 1300kv motor, should I down size prop to 10 x 4.5
I have the same motor. Just a heads up: Your ply, stock motor mount will need to me strengthened and made a tad bigger. The X mount on your new motorwill BARLEY fit on the stock mount. All I did was cut a slightly bigger, thicker ply mount and installed four blind nuts on the new ply mount for the X mount. Then I adhered the new mount to the old one using Goop Automotive. I have about 100 flights on it with NO problems It seems to be an amazing motor. Great quality with gobs of power.
SubaruMike is online now Find More Posts by SubaruMike
RCG Plus Member
Reply With Quote
Old Jul 30, 2013, 09:21 AM
Registered User
RCstudent's Avatar
United States, WA, Bellevue
Joined Jan 2013
283 Posts
You don't necessarily need a bigger mount... Mine is on the stock mount, but I did pre drill 2 extra holes on the mount to make the X fit.. I used loctite on the screws, it's still as strong as before... Also I ran some gorilla glue super glue( the clear stuff) down both sides of the mount just to make sure it doesn't move. But you will love that motor... I haven't watt tested my power setup, but the 10x4.7 does great things... Throw the 11x4.7 prop on and test it before you fly... But the motor is rated at 420watts... Let me know how the test goes.
RCstudent is offline Find More Posts by RCstudent
Reply With Quote
Old Jul 30, 2013, 09:46 AM
smoke is my wattmeter
Longview, Tx
Joined May 2008
1,124 Posts
I tried the lower kv eflite 480 and I thought it was very weak. I've heard the 1020kv model is much stouter. Personally I think this plane needs over 300 Watts to make of fun.
krexken is offline Find More Posts by krexken
Reply With Quote
Old Jul 30, 2013, 09:56 AM
Registered User
RCstudent's Avatar
United States, WA, Bellevue
Joined Jan 2013
283 Posts
I've actually seen a 3536/8 1000 kv on this plane... Plane felt a little heavy when I test flew it, but the power was crazy! You could pull out of anything, but again you sacrifice weight and if you're trying to learn 3d you need as less wait and as floaty as possible... I think the 3010b is the best fit on this plane.
RCstudent is offline Find More Posts by RCstudent
Reply With Quote
Old Jul 30, 2013, 11:48 AM
Shore Huckin'
KE Spin's Avatar
Ohio
Joined Aug 2010
2,693 Posts
Quote:
Originally Posted by natwill View Post
Thanks for your reply, the battery seems ok from testing on the watt meter, admittedly it had about 60% but I thought that this shouldn't matter, I have ordered a higher kv motor, hopefully a few more rpms will do the trick
When you said, "it had about 60%" what did you mean by that? It had 60% of what?

The 480 motor will deliver around 275 watts which is plenty of power for a plane this size. Any larger is just extra weight and will try to tear the plane apart. A plane of this size will generally be ok with a 450 sized motor.

With regard to getting more rpm by moving to a higher kv motor, this may not be the magic answer. While it is true that a higher kv should give more rpm it must be noted that you may need to use a smaller prop to achieve the higher rpm or risk over heating the motor.
KE Spin is offline Find More Posts by KE Spin
Reply With Quote
Old Jul 30, 2013, 06:11 PM
smoke is my wattmeter
Longview, Tx
Joined May 2008
1,124 Posts
Mine weighs right at 30 ounces with an 80 gram motor, cheapie mgs, 30 amp esc and 1550s. Not exactly a flyweight.
krexken is offline Find More Posts by krexken
Reply With Quote
Old Jul 30, 2013, 06:34 PM
Shore Huckin'
KE Spin's Avatar
Ohio
Joined Aug 2010
2,693 Posts
Just double checked the specs and I guess this thing is something of a porker but my AJ Slick (42") weighs in at a little over 33oz and hovers easily with an E-flite 480.

I had a 39" Sbach that flew fine with a 480 and currently still have my Parkmaster that actually is flying on a 450 size motor...not stunning verticals but hovers easily.
KE Spin is offline Find More Posts by KE Spin
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Twisted Crack Yak 55 - power issues dr_jones 3D Foamies 23 Mar 26, 2014 11:56 PM
Gallery Yak 55 (u-can-yak) houstondominant Your Plane Photos 0 Jul 20, 2005 09:08 PM