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Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  RknRusty on Thu Sep 28, 2017 8:13 pm

Just when I thought I'd figured out all of my Killer Bee facts, I now find that early ones had a 128tpi NV. Till now, I had always believed that No KB ever had a fine thread NV ... Banging my head on the keyboard!

However, that detail really makes almost no difference unless you are feeding it pressurized fuel. On suction, it may make it slightly easier to adjust, but that's about all.
Rattled Rusty

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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Thu Sep 28, 2017 9:28 pm

Yes less machine time to make the 2nd gen type, the fine thread version came from a first gen 051.
I will be doing a bench test with the Nelson plug and a stock Tornado 5x3. it's in good shape and
should yield similar results as a Cox 5x3 and expect to milk extra rpm with the fine thread needle
and another 500 ish rpm with the Nelson plug so the variance could be as much as 1k ish boost on
25% nitro. Standard hard tank no pressure.






Last edited by 1/2A Nut on Fri Sep 29, 2017 8:53 am; edited 1 time in total
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Thu Sep 28, 2017 11:48 pm



Cox 5x3 built up engine from Killer Bee parts
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Fri Sep 29, 2017 9:31 am

1/2A Nut wrote:

Cox 5x3  built up engine from Killer Bee parts

yes, it is possible that my engine has a difference from the video, I suppose it must be the type of fuel and that my engine has some obstruction (even full gas), the acceleration ring.
I think finally in a beautiful copy of Killer Bee version II Thumbs Up
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Fri Sep 29, 2017 2:39 pm

Yes he was using 25% nitro best sustained 18,540 rpm with a Cox grey 5x3
With yours and a throttle ring 17,880 is good for the Cox black 5x3 / how much nitro?


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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Fri Sep 29, 2017 3:34 pm

Fired it up on my lunch break for a quick check it is loud!
Think I can milk some more out of it will mess with it this weekend.

Tornado 5x3 / 25% nitro / nelson plug / 128 tpi.

Static: 21,883rpm / 13.75oz thrust / 62.1 mph / .141hp / 76.84w

Want to try the Cox yellow 4.5x4 for a bit more pitch speed.
Also the HQ Prop Carbon 4x4.5 for top end reed speed.





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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Fri Sep 29, 2017 9:56 pm

1/2A Nut wrote:Fired it up on my lunch break for a quick check it is loud!
Think I can milk some more out of it will mess with it this weekend.

Tornado 5x3 / 25% nitro / nelson plug / 128 tpi.

Static: 21,883rpm / 13.75oz thrust / 62.1 mph / .141hp / 76.84w

Want to try the Cox yellow 4.5x4 for a bit more pitch speed.
Also the HQ Prop Carbon 4x4.5 for top end reed speed.





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Hi Brad, here I am having a beer watching your report and photo Smile !, excellent !, that engine "flies", according to the manual that I own, the maximum is 22,000 rpm, so you are a sigh to arrive ... very powerful ! Clapping
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Fri Sep 29, 2017 9:57 pm

1/2A Nut wrote:Yes he was using 25% nitro best sustained 18,540 rpm with a Cox grey 5x3
With yours and a throttle ring 17,880 is good for the Cox black 5x3 / how much nitro?


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25% Nitro
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Fri Sep 29, 2017 10:55 pm

Yes 22k looks like the recommended max, thank you for the Greene's Very Happy
Gave you some on this thread too my friend Thumbs Up

I think I will try for 22.5k with the Carbon HQ Prop 4x4.5 and be happy.
Matt from Cox  Ex model engines sells the Killer Bee crank you can increase the
performance of yours!


http://www.exmodelengines.com/product.php?productid=17675&cat=0&featured=Y


Beer Cheers







Last edited by 1/2A Nut on Sat Sep 30, 2017 6:19 am; edited 1 time in total
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Fri Sep 29, 2017 11:20 pm

thanks to you for such good information.
If I have seen many accessories and spare parts, but I am trying to get the contact of those who do the service of bringing things from the US, because here many things are held in customs for several months and others pass quickly, I hope to find the right way. My country is in a process of restructuring due to many problems of mismanagement Paranoid
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Fri Sep 29, 2017 11:50 pm

I can buy the crank and send it to you if that will help?

Next test Cox 4.5x4
I have replaced the back plate to the 78 tpi threaded version to see if there is more
effort to set the NV and elevated the back plate to allow better airflow into the intake.
Should help to increase power perhaps another 10w or so.  

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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 2:35 am

Hey Brad, you're very kind to me and I value your gesture a lot. If you ever want to travel my country, just let me know, You will have food (and good) and my house to stay, I offer it from my heart! besides going to fly clear !!

I am waiting for a relatively important order of a few accessories, (April makes) that my contact bought them, but I still do not deliver them, I do not know whether it is a problem of it, or a problem in customs, he tells me that he is about to receive it, but it has been several months and I am still waiting.

Some time ago Mr. Matt was looking for testers of his vénturí and needle for Tee Dee 049/051, I offered and kindly agreed, he sent it directly to my address and arrived between 7 and 10 days! ... I asked in the mail and I was informed that just that, can happen that does not delay or that they have it retained for a long time in the customs.

I will wait another time and if I do not receive this order that I have pending, I will be testing with other people who (say) do the service.

In any case if I have no way I could think of bothering you, for this I ask you, You could receive money through Western Union ??

Regarding the Killer Bee, has the wood drilled in the back, just so you can take air without restrictions .... besides, I did different tests, put another needle (just to test), remove the regulating ring and also changed the level of the fuel tank, the engine still marching the same (17880/ 17950 rpm)

Thanks again, my friend...




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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sat Sep 30, 2017 6:51 am

Thank you Mauricio!

No need for Western Union I have just bought two of them you can have one!
With all the money you have invested, you deserve to enjoy the proper performance.
Should get another 1,100 rpm with the correct crankshaft my guess, will be a treat to see
the results.


Just PM me your address I will send it direct. Beer Cheers

Matt will be sending me this order:
Sold by esp-ex3460 ( 7896 )
http://www.ebay.com/itm/272294481213

Payment date
Saturday, Sep 30, 2017
Estimated delivery Saturday, Oct 7, 2017

Cox .049 .051 Airplane Engine Killer Bee Crankshaft - High Performance 049 051

Quantity 2
Item number 272294481213
Shipping service USPS First Class Package

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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  getback on Sat Sep 30, 2017 9:32 am

You guys are just having all the fun in this thread Smile Great gesture for sending Mauricio some parts to play with ! I only have one killer bee crank in a engine case that i have yet to tear down , kind of funny it has a muffler on it Huh... No pic my son has the camera were he been making guitar videos of himself playing . I know my entry in the tach race got 21,890 out of a TD pis/cly set , red back plate and fine thread needle i think if i remember right 4.5x4 prop Ron was using ? i do like the yellow prop for Cox though https://coxengines.ca/cox-.049-propeller-yellow-4.5-x-4.html tough and plenty of air thrust ! Popcorn not beer time yet tongue
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 11:38 am

1/2A Nut wrote:Thank you Mauricio!

No need for Western Union I have just bought two of them you can have one!
With all the money you have invested, you deserve to enjoy the proper performance.
Should get another 1,100 rpm with the correct crankshaft my guess, will be a treat to see
the results.


Just PM me your address I will send it direct.   Beer Cheers

Matt will be sending me this order:
Sold by esp-ex3460 ( 7896 )
http://www.ebay.com/itm/272294481213

Payment date
Saturday, Sep 30, 2017
Estimated delivery Saturday, Oct 7, 2017

Cox .049 .051 Airplane Engine Killer Bee Crankshaft - High Performance 049 051

Quantity 2
Item number 272294481213
Shipping service USPS First Class Package

Computer Issues

Thank you very much again, I will send an MP, thanks again.
I have the blessing of having many friends in my country, people I visited in contests and meetings, many also come to my city and to visit me, you will be on that list friend Brad! Beer Cheers
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 11:45 am

getback wrote:You guys are just having all the fun in this thread Smile Great gesture for sending Mauricio some parts to play with ! I only have one killer bee crank in a engine case that i have yet to tear down , kind of funny it has a muffler on it Huh... No pic my son has the camera were he been making guitar videos of himself playing . I know my entry in the tach race got 21,890 out of a TD pis/cly set , red back plate and fine thread needle i think if i remember right 4.5x4 prop Ron was using ? i do like the yellow prop for Cox though https://coxengines.ca/cox-.049-propeller-yellow-4.5-x-4.html tough and plenty of air thrust ! Popcorn not beer time yet tongue

That is the beauty of the Forum, that one finds very good people with the camaraderie and kindness of sharing to grow the activity and to continue for many years.
Friend Eric, here is a video of you, is it a bee?


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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sat Sep 30, 2017 12:55 pm

Brief peak at 20,106 till it warmed up.
Best steady peak 19,622 but never maintained a steady peak for long although did
hit 19,622 multiple times so that's a good number.

Cox Yellow 4.5x4
Static 6.7oz thrust / 74.3 mph / .089hp / 66.4W

Mauricio lets hope this photo insures it happens!!!
Beer Cheers






cheers
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 1:24 pm

1/2A Nut wrote:Brief peak at 20,106 till it warmed up.
Best steady peak 19,622 but never maintained a steady peak for long although did
hit 19,622 multiple times so that's a good number.

Cox Yellow 4.5x4
Static 6.7oz thrust / 74.3 mph / .089hp / 66.4W

Mauricio lets hope this photo insures it happens!!!
 Beer Cheers






cheers

Yes !!, hahaha, that number is made of my fist and letter with a brush !, I was never lyricist! LOL
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sat Sep 30, 2017 3:01 pm

LOL yes will let you know when I ship it with a tracking number for you to monitor and know when it arrives.  Eyebrows


Ok tested the Cox yellow 4.5x4 here are the results:





AmpAbuser
Published on Sep 30, 2017

Mirror polished inside cylinder walls, light weight 2.8g tapper piston,
high performance crankshaft, 78 TPI needle valve. Using a Galbraith head
and Nelson glow plug, the only non stock addition to this bench test.  

Bench test specs:
Cox yellow 4.5x4 / Best noted peak at 20,510 rpm  
7.8oz thrust / 78mph pitch speed /.101hp / 75.4W
20% castor / 25% nitro air temp 72F / 2 head shims.
May 31st 1995 Made Date / Engine No. 340
Engine has about 6.5oz of total running to this bench test.
NV was set at 4.75 turns hard tank no pressure, about 1/4th turn rich.
This is the only known vid of a real stock 1995 Cox made Killer Bee on Youtube

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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 4:26 pm

1/2A Nut wrote:LOL yes will let you know when I ship it with a tracking number for you to monitor and know when it arrives.  Eyebrows


Ok tested the Cox yellow 4.5x4 here are the results:





AmpAbuser
Published on Sep 30, 2017

Mirror polished inside cylinder walls, light weight 2.8g tapper piston,
high performance crankshaft, 78 TPI needle valve. Using a Galbraith head
and Nelson glow plug, the only non stock addition to this bench test.  

Bench test specs:
Cox yellow 4.5x4 / Best noted peak at 20,510 rpm  
7.8oz thrust / 78mph pitch speed /.101hp / 75.4W
20% castor / 25% nitro air temp 72F / 2 head shims.
May 31st 1995 Made Date / Engine No. 340
Engine has about 6.5oz of total running to this bench test.
NV was set at 4.75 turns hard tank no pressure, about 1/4th turn rich.
This is the only known vid of a real stock 1995 Cox made Killer Bee on Youtube

Small Cox Logo

Excellent Brad !!.
Regarding the video, very good, you have reached the limit with your bee! Congratulations!

Here only to have a parameter, I used a Black Widow engine with killer bee plate and high compression glow plug (it's my killer Bee) ... it turns out to give 17,040 rpm with Cox 5x3.








Last edited by MauricioB on Sat Sep 30, 2017 4:45 pm; edited 1 time in total
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sat Sep 30, 2017 4:42 pm

Yes the 1995 KB should make for a nice 90mph RC plane with a thin carbon 4.5x4

OK so your current Killer Bee configuration:
17880/ 17950 rpm

VS

Black Widow:
17.040 rpm

840 to 910 rpm more with the current KB, the flywheel should give you a good
jump in power for thrust or speed as needed.


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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 4:47 pm

1/2A Nut wrote:Yes the 1995 KB should make for a nice 90mph RC plane with a thin carbon 4.5x4

OK so your current Killer Bee configuration:
17880/ 17950 rpm

VS

Black Widow:
17.040 rpm

840 to 910 rpm more with the current KB, the flywheel should give you a good
jump in power for thrust or speed as needed.


RC Plane

Very Happy Thumbs Up Beer Cheers Small Cox Logo
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sat Sep 30, 2017 5:37 pm

3rd test HQ Prop Carbon 4x4.5


Static 25,193 rpm / 107mph / 7.1oz thrust / .132hp / 98.47W


The carbon prop weight is half of the cox yellow prop and the blades do not
have a dull leading edge like the kid friendly cox prop, result is a big boost
in performance. Competition drone racing prop with a thick airfoil at the hub, I have
spun these up at 38k with no failures with a high performance car engine and tuned pipe.
Many many flights the rpm is so high thrust is fantastic.  

Leaner NV setting around 3.5 turns screamer but the unloaded rpm would exceed the
reed valves ability to maintain function. Est. 29k ish. The HQ 5x4.5 would be a good prop
for actual flying around 23.5k unloaded. 100mph + Reedie RC plane. The lighter carbon
mass and thinner airfoil will not tax the ball socket near as much insure long engine life
they have a high tolerance design in balance and shape to insure smooth rpm and tight
prop bolt fit for excellent centering.

Small Cox Logo







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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  MauricioB on Sat Sep 30, 2017 11:36 pm

1/2A Nut wrote:3rd test HQ Prop Carbon 4x4.5


Static 25,193 rpm / 107mph / 7.1oz thrust / .132hp / 98.47W


The carbon prop weight is half of the cox yellow prop and the blades do not
have a dull leading edge like the kid friendly cox prop, result is a big boost
in performance. Competition drone racing prop with a thick airfoil at the hub, I have
spun these up at 38k with no failures with a high performance car engine and tuned pipe.
Many many flights the rpm is so high thrust is fantastic.  

Leaner NV setting around 3.5 turns screamer but the unloaded rpm would exceed the
reed valves ability to maintain function. Est. 29k ish. The HQ 5x4.5 would be a good prop
for actual flying around 23.5k unloaded. 100mph + Reedie RC plane. The lighter carbon
mass and thinner airfoil will not tax the ball socket near as much insure long engine life
they have a high tolerance design in balance and shape to insure smooth rpm and tight
prop bolt fit for excellent centering.

Small Cox Logo








Hi !, all this information is very valuable, make these experiences and show the results makes many interested parties cut way and do not err when buying one or other accessory, it is very different when you invest money, take your time, do the experiences and discards material .... so a tester is valuable even for those who sell material. I think Brad, that his contribution is very valuable for the forum and to highlight his accurate information, with genuine data.
First of all I thank you for sharing your experiences and congratulate you on the teaching and sharing of teaching.
I think in this forum there are very valuable people with a lot of knowledge, You are one of them! the forum in general should feel very happy to have members of this tenor!
A hug and thanks for all this precious data!
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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

Post  1/2A Nut on Sun Oct 01, 2017 2:23 am

Thank you and happy to do Small Cox Logo

I plan to do one more test perhaps the most important one HQ 5x4.5 carbon prop which will
fit well with this engine providing fantastic thrust and speed for a reed valve engine.

If the data is good I would like to build a Speedy Reedy RC plane with a special firewall to
suit the reed engine's back plate for improved air intake. My goal is to have a good video
of a 100 mph + reed powered RC plane something that I have never seen yet. A custom
cut 4.5x5 will be good for top end speed.





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Re: Buy a Cox! ... but, what exactly do you buy?: KILLER BEE .051 1996

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