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Eggvoel
11-14-2005, 05:24 PM
Is anyone flying one of these motors and on what type and weight airplane. Thinking of putting one on my Formosa and Estarter and wondered how the verticle performance would be. Also, would it fly with just a 2c lipo. I'd like to use them also since I have them and get a 3c for the extra boost. Thanks. Larry

ForestCam
11-14-2005, 05:45 PM
Made my formosa fly like a dog, largest prop I could run on a 3c was a 8x6.

Switched to an EP283012-970KV outrunner from GWSExpert.com and I love it! Plan on getting another as soon as I score a ARF CAP-232 off ebay.:D

http://www.wattflyer.com/forums/attachment.php?attachmentid=3723&d=1131599878

Steve
11-14-2005, 06:13 PM
I'm flying one now on a foamie I built called an "STC". I think that with battery, it weighs about 12oz or so. Goes just fine with the 8x6 prop and 3cell 1350 lipo.

I think it does well in most cases where you're looking to replace a geared 350 brushed motor. Not sure what RPM's it's turning.

It will run on a 2cell...just about 1/2 the power which may or may not work for you.

Eggvoel
11-14-2005, 10:40 PM
Thanks Forest Cam & Steve for the quick replies. They claim 21 oz. of thrust at 11.2v, so it seemed that with a 16-17 oz. plane it would do better than the 350 geared. Just starting my research on this now and will check out other sites I had previously visited over the past year. This upgrade is coming from Santa who has a limited budget. Larry

Steve
11-15-2005, 11:59 AM
Yeah....information about the real numbers for this motor seems to be a bit sketchy. Maybe 21oz of thrust with the 1047 prop? I don't have a thrust meter, but that number seems high. What do I know.....

Personally, I would go with an AXI or one of those outrunners that HobbyPeople (lobby?) are selling for $30.Eskay...or something like that.

Eggvoel
11-15-2005, 05:12 PM
Looks like I am going to have to look not only at thrust ratings, but also the amp draw, etc. I have a lot of homework to do. Thanks. larry

Bil2
11-29-2005, 02:35 AM
Hobbypeople.net has a good deal going on now in their catalog. Phase 3 foamie, 4 different models, $29.99 each, but for another $10 you get an outrunner B/L motor and motor mount. Motor is KMS brand, model KBM 31/21. Got one under my Christmas tree right now! (Grin....) Bil

qban_flyer
11-29-2005, 02:52 AM
Yeah....information about the real numbers for this motor seems to be a bit sketchy. Maybe 21oz of thrust with the 1047 prop? I don't have a thrust meter, but that number seems high. What do I know.....They indeed appear to be so. Current draw is high too.

Personally, I would go with an AXI or one of those outrunners that HobbyPeople (lobby?) are selling for $30.Eskay...or something like that.

Hobby Lobby sells the Esskay 400XT for $29.90, everybody else is charging as much as $49.99 for the same motor. H/L just had a sale on them at $19.90 for one hour on Black Friday.

Keep checking their web page as they change their Sale Specials every Thursday after they close. When I bought mine I got them @ $24.90 each. I own six of them so far.

Great motors, extremely powerful and silent! :)

GallopingGhost
11-29-2005, 02:55 AM
Is anyone flying one of these motors and on what type and weight airplane. Thinking of putting one on my Formosa and Estarter and wondered how the verticle performance would be. Also, would it fly with just a 2c lipo. I'd like to use them also since I have them and get a 3c for the extra boost. Thanks. Larry

I have two of them and they run great for me. One is on a "3D Flipper" which is a big Foamie 37" and weighs in at 19oz. It will pull a 9X3.8 without getting overly warm. Only thing is it wants 15 plus Amps at WOT. The other is on a FFF "Maverick" a SleezeBay kit I picked up for $3.00, pretty nice for the money! Shipping was twice the cost of the kit! Its a smaller plane and it does pretty good at 1/4 to 1/2 throttle which keeps the Amps down. I have no reason to complain about the BP's but the Hobby Lobby XT 400 is about the same money when on sale and is much better looking construction. I think Balsa Products has a new version(BP12?) that will do better with the bigger props on less Amps.
Ooo by the way mine run great on 3 Cells but barely flew on 2C.

Dr Kiwi
12-03-2005, 01:42 AM
I think Balsa Products has a new version(BP12?) that will do better with the bigger props on less Amps.


I've seen ads for the BP 12 for ages - I've always thought it seemed, on paper, to be the better motor, but everyone has taken to the BP 21???? I've never tested either, though, through the generosity of Andrew at AWL Hobbies, a BP 21 is on its way to me for testing as we speak.

Cheers, Phil

Steve
12-03-2005, 02:00 AM
I'm running my BP21 with 3s and an 8040dd prop. It draws about 12A WOT static, so with my 1320mah lipos, I think it's pushing them a bit. I don't fly WOT much to protect the batt from over discharge.

Just moving up to an 8060 APC, it pulled almost 17A, so I had to back it down. My ESC and batt didn't like the pressure.

I'm going to try the Esskay motor setup Qban suggests on my next ride....

Rittenflyer
12-03-2005, 06:05 PM
Is anyone flying one of these motors and on what type and weight airplane. Thinking of putting one on my Formosa and Estarter and wondered how the verticle performance would be. Also, would it fly with just a 2c lipo. I'd like to use them also since I have them and get a 3c for the extra boost. Thanks. Larry

I converted a GWS P51 from 350 gearbox to BP12 outrunner with 3s 1320 lipo and 8x4 prop. My plane is 16.5oz all up and flies like a certain kind of ape. Vertical is just fine for a plane this size and might even challenge those with weaker eyes.

Sean Rittenhouse

roccobro
12-03-2005, 07:06 PM
I have one of my GWS F4Us with the BP21 and 8040 on 3s. Pulls 12 amps static,and has way more power than my Himax 4200 with 9x6 on the same batts. Verticals to out of sight are easy. Both Plane are around 15 oz's.

And Steve- The 1320's PL's are great. I've had mine up to 17 A continious in some Alfa EDF plane tests and they were 5 deg above ambient when done.

Justin

Steve
12-03-2005, 07:11 PM
Good to know Justin. I'm thinking I have a F4U in my immediate future so all I'll need is a couple of servos and I'll be all set....I have everything else.

Steve

Steve
12-03-2005, 07:12 PM
BTW...do you have any links to good GWS F4U build/mod threads?

roccobro
12-04-2005, 02:15 AM
There is one going on right now if I'm not mistaken. I built my first one completely stock, but some more down thrust is needed with the higher power motor.

Justin

rahtware
02-05-2006, 01:07 PM
I decided to buy one of these after flying my Stryker with it's stock 480 (broken in and timed) against a heaver Stryker on a BP-21... The vertical of his setup was over twice that of mine and he had about a 20% advantage in speed over mine. Not outrageous, but for a $50 (with ESC) upgrade I feel it was worth it.

Eggvoel
02-06-2006, 05:25 PM
`I posted this info elsewhere on this sight, but will restate it here. I opted for the BP08Y from Balsa Products instead of the BP21. I was looking for something that would turn a larger prop, wanted more pulling power than speed. My Formosa gets too far away too quickly anyway. Now have 5 flights on this motor with 3c 1500ma battery. Had stock GWS 350 with c gearing and 9070 prop with 2c lipo. Been a great aerobatic trainer, but now it is a GREAT flying plane. Having loads of fun at way less than full throttle and the power is there when you need it. No having to wait to gain altitude, you are there! Presently using a GWS 1047 prop and will try an APC 1147 when prop adapter comes in.
Tried flying it with 2c lipo and 9070 prop and it wouldn't stay up. Haven't flown until LVC yet, but getting a good 15 minutes with varied throttle settings. FUN! Larry

rahtware
02-07-2006, 12:55 AM
I would love to try the other BP motors on the Stryker, but am limited by the clearance between the fins... Maybe when I get around to finishing myFlatOut Cap... :D