upgrading an old thunder tiger sparky 400 to a brushless setup - RC Groups
Thread Tools
Mar 04, 2012, 06:47 PM
Registered User

upgrading an old thunder tiger sparky 400 to a brushless setup

when i was about 14 i bought an ARF sparky 400 kit and built it, it took me a long time to get the courage to go and try to fly it and when i did it did a nose dive then the motor wouldn't start, so i just hung it in my room and left it, years later I now have several little planes that I fly and i went and found the dusty old guy in my parents basement, I quickly diagnosed and repaired the problems and charged its old NiMh batter and took it to really fly it for the first time, the motor could barely get it off the ground and it only flew for about 30 seconds before the battery died, still i was surprised it few after all that time.

Now my Question is this, I want to upgrade the plane to an new brushless setup, so as far as i know ill have to replace the motor of course, and the esc, i also already threw in a spektrum receiver i just need some help deciding which ones to use, im still not too good and getting that all right. based on my little knowledge of motors and escs, the size of the area where the motor will have to be mounted and the types of batteries i already have i've decided on this setup, let me know if this would work, also sorry for making a new post if one already existed, but RCgroups search wasn't working.

these are the batteries i already have and use for several other planes, so if at ill possible id like to stick with them.

I plan to use this motor without a gearbox


and im planning on getting this esc to go with it

would that be a good setup? the way the plane is set up i really need to stick with an inrunner, but i still fear that that motor is going to be a bit overkill for a parkflyer 3ch plane, also which props would you guys recommend?
Sign up now
to remove ads between posts
Mar 05, 2012, 02:52 PM
Registered User
bump? anybody got an opinion on these?
Mar 05, 2012, 04:38 PM
Some Girls r Bigger thn Others
swps's Avatar
I'd say that 2600kv is too much for this plane even with a prop the right size. I just don't see it holding up to that.

I'd get the 1370kv version and swing a bigger prop.

Or maybe the 1500kv version if the prop clearance won't work with the 1370kv.
Mar 06, 2012, 01:42 AM
Registered User
thanks for the input, i thought that motor would be a bit quick for the plane, it's got some pretty big landing gear on is so prop clearance shouldn't be a problem, but as far as esc and battery go, i'd need to get a beefier esc for that motor, which would you recommend? i seem to have a hard time finding in product description which ones have a bec or not, and i don't want to do a second battery for the rx. would this one work?

what about this one? does it have a bec?

they both have some form of bec, but it's always got some prefix, like ubec, or sbec, i just wanna be sure
Last edited by hermanmango; Mar 06, 2012 at 01:48 AM. Reason: added links
Mar 06, 2012, 11:14 AM
Some Girls r Bigger thn Others
swps's Avatar
You could keep the original ESC you had on 3s and be fine or prop down on 4s until you were under the rated Amps. BUT that being said, any of those motors are going to make that plane scream and will probably rip the wings right off.

Both the ESCs you have listed above have internal BECs. I personally prefer to get an external one, in case the ESC frys I can still control the plane.

I would avoid the red brick ESC, I have not heard good things about them.

I like these ESCs, they are made by Hobbywing and are excellent quality. You can get them with or without internal bec (without is listed as OPTO).

or get the Hobbywing.

I like these external BECs from HK but are currently out of stock.

And these ones are Hobbywings repackaged as Exceed and are fantastic and in the USA.
Mar 07, 2012, 09:53 PM
Registered User
after looking around i think ill just try to modify the plane to use an outrunner, they seem to be more in the power range i want, as for mounting it do i need a special motor mount? or just fit some balsa in there and mount it to that
Mar 08, 2012, 07:02 AM
Sussex, UK
RobinBennett's Avatar
An outrunner would make sense - a slow flier like this would probably be better with a 1000-1200kv motor (if you're using a 3s battery). 1500Kv is for sport models (IMHO)

Most HK motors come with a mount, but you'd need to glue in a plywood or liteply firewall. If you use balsa, laminate a couple of layers at 90 degrees to prevent it splitting.

If you pick an outrunner of similar weight to the speed400, it'll be a lot more powerful, probably too powerful for the model. If there's scope to move the battery forward you could save quite a lot of weight by picking a lighter motor.

Something like this would have about twice the output power and be half the weight of a speed 400


Why are you looking at 70amp ESCs? Even the burst rating on your battery is only about 30amps - and the speed400 would have used about 10amps at full power.

Most of the ESCs under 40amps have a BEC, and with only two servos you'll be fine with a linear 1amp BEC (the better ESCs have a 3amp switching BEC, which you need for 4 servo planes)

This one should do you for $6 (some of the Super Simple ESCs have poor reviews, this one seems OK) Or you could pay a bit more for the better quality Turnigy one. I tend to order both when they are this cheap and if the cheap one doesn't work I've not lost much (and they usually work fine)

Mar 10, 2012, 05:11 AM
Registered User
thanks for the input, ya, im still trying exactly to figure out how to choose motors and such, i found a pretty good package deal on heads up RC that i think will work well for this plane


not the cheapest on the internet, but I've heard a lot of good things about this website, and I wont have to deal with HK shipping, stock issues, and customer support.
Mar 10, 2012, 05:46 AM
Sussex, UK
RobinBennett's Avatar
That should work nicely, and will cope with more power than your battery can supply.
Mar 14, 2012, 06:23 PM
Registered User
well, I'm heading out to maiden her right now, wish me luck, ill let everyone know how it went.
Mar 16, 2012, 05:29 AM
Registered User
flew great!, had way to much up elevator so i had to trim the crap out of it to get stable flight, but that was on purpose, better to have too much up than too much down. the motor was a little more power than the plane needs, and I can flip loops with it pretty easy, but still it flies it well without ripping the wings off. it was nice to see the thin finally fly after so many years. thanks for everyone's input
Mar 16, 2012, 05:41 AM
Sussex, UK
RobinBennett's Avatar
Excellent result, well done!

You may find you need more downthrust to prevent it climbing too much when you open the throttle, but the exact amount is down to personal preference.
Jun 11, 2017, 08:38 PM
Registered User
circletree's Avatar
Anyone still flying a Sparky? I just bought one off CL and plan on the maiden flight in the am......brushed speed 400 motor and all! I'm planning on swapping to a brushless motor and a 3S battery to make up for the weight loss between the BL and the ancient speed 400 with a gearbox.
Jun 12, 2017, 08:53 AM
Registered User
circletree's Avatar
Maiden flight this morning.......what a beautiful "old timer" Sparky is! Nothing more than a Sunday flyer, and that is fine with me. I gained about 250' and throttled back to just ticking over, trimmed for a wide right circle and let Sparky free fly until it got a little too far away....trimmed rudder back and flew it back to me. Beautiful!
Jun 14, 2017, 10:26 AM
Registered User
The Sparky is a great plane. I have flown a couple of them, when they were still being manufactured, with the stock set up and they flew well. A couple of years ago, I found one on the auction site and it is hanging in my hobby room waiting to be flown.

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
AP from Thunder Tiger Sparky 400 tdavis Aerial Photography 11 Feb 04, 2013 09:48 PM
For Sale REDUCED!!RTF!!!Thunder Tiger Sparky 400 Super Combo Brushless!! Trade? kramer Aircraft - Electric - Airplanes (FS/W) 17 Oct 09, 2011 04:44 PM
For Sale Thunder Tiger Sparky 400 ready to fly. 2robinhood Aircraft - Electric - Airplanes (FS/W) 0 Oct 25, 2007 08:22 AM
want an oldtimer? get the thunder tiger sparky! someone special Parkflyers 3 Apr 30, 2003 10:46 PM
Thunder Tiger Sparky 400 In Flight RC4x4 Parkflyers 14 Aug 22, 2002 10:51 PM