Notices
Glow Engines Discuss RC glow engines

K&B .65 Sportster

Old 04-11-2012, 01:42 PM
  #76  
woodburner
 
Join Date: Jun 2007
Location: Alpharetta, GA/Sao Paulo, BRAZIL
Posts: 123
Likes: 0
Received 0 Likes on 0 Posts
Default RE: K&B .65 Sportster


ORIGINAL: Sport_Pilot

Does K&B not sell their carbs? Just a tad better than the Perry carbs IMO. Especially the latest one with the wire detent on the idle disk.

See part 80-5801 on this list: [link]http://www.mecoa.com/kb/58/58-parts.htm[/link]
Old 11-06-2016, 11:59 AM
  #77  
smr2ley
 
Join Date: May 2006
Location: , UNITED KINGDOM
Posts: 10
Likes: 0
Received 0 Likes on 0 Posts
Default

I had a "91" 65 sportster back in 92-96, bought from a US airforce guy in my English model club. He had removed it from a drone, and changed the carb and it was really reliable. I flew it at every opportunity over 4 years, in an original foam wing Chris Foss Acrowot, on a 13.7 prop. It never gave me any problem, was faultless, always started easily with a flick or starter, idled perfectly, never ever cut out on me once. Best motor I ever owned.
I have another now after a big gap in the hobby from 97 to 2015, this one was bought while on vacation in Vegas in 2003, I went to Mecoa for it. It stayed in the box in my office bedroom until mid 2015. Carb was found to be seized absolutely solid - couldn't budge it (in closed position of course....) Mecoa were great, sent me another carb foc ! I did manage to free that carb later, by heating some oil till it smoked and threw the carb in, and left it for the day and night, but it was still solid so I did it again and THEN at last it turned and I took it apart. Now it's ready as a spare. Been running this new engine in recently as per the articles with castor, ready to fly now but weather over here is now crap.
In England not one person I speak to either ever heard of a K&B engine, or has the idea they were rubbish (and these guys are in their late 60's or 70's). The look on their faces when I produced it to give it a run in a corner of the flying field, with a 13x7 prop was comic; they all shouted it should be 11/6.
I only know K&B because having first started out to learn in 81 with the obligatory high wing trainer running a .35, then in 82 or 83 I bought a K&B 6.5cc ducted fan engine that had a rear can exhaust fitted, from some modelling shop I saw in the old RC Modeller mag. I used this in the same now old trainer, that had been smashed up more than few times in my earlier days; this trainer now went vertical straight out of your hand, just held it pointing up about 80 degrees, pushed the throttle just over 3/4 and let go. I was a K&B man now through and through. I bought another K&B .45 ducted fan, in a Hawk and then F15, then a 46 Sportster, and finally came my first 65 Sportster.
Near my home in Oxford here in England was a USAF base, from which this NYer came, also a couple more guys joined our club; one of them was from Atlanta he allowed all us Brits to use his USPO box to get stuff through Tower Hobbies nearly every week, shipping this way was amazingly cheap, also we didn't have to pay any duties as we would have if ordering through our own addresses. I remember quite a few other members in that club bought K&B 65 Sportsters after seeing mine. In 93/4 I got the Great Planes Learjet through this US member, and out came my original ducted fan engine, I had a specialist on the southcoast bend me a header for a tuned pipe that I managed to hide in through the lower part of the big fuselage; on a 10x6 prop,and 20% nitro, it turned over 18000 rpm and that thing absolutely shook the club up when they saw it fly.

Last edited by smr2ley; 11-06-2016 at 12:57 PM.
Old 06-26-2017, 08:12 PM
  #78  
beachsideflyer
 
Join Date: Apr 2017
Location: Satellite Beach, Florida
Posts: 25
Likes: 0
Received 0 Likes on 0 Posts
Default

This motor will not run properly on fuel with over a 10% nitro content. Also, mix an ounce of castor oil per quart to your synthetic oil fuels to keep everything cooperating. I run a 13/5 prop. Just do it!
Old 11-02-2019, 01:58 AM
  #79  
tooth-pick
Junior Member
 
Join Date: Nov 2019
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default

So I have one of these on an OLD Ace Bingo 60. I have never managed to keep it running for a whole flight. However my problem is REALLY strange and I've found no reference online to it. Problem is, the engine always wants to run BACKWARDS! 80% of the time, flipping it with chicken stick, it fires and immediately changes direction and actually runs perfectly normal in the clockwise direction. However, I fear this could pose a problem with the flight aerodynamics!!! When it is running forwards, it will usually violently and instantaneously reverse with no sputtering or anything besides a loud crack like a gunshot from the physics defying abrupt reversal. This even happens at full throttle during flight and of course always shoots the prop nut off like a bullet. At lower speeds, it will reverse while humming perfectly at steady RPM and, if the prop stays on, will continue to run at the same RPM in the backwards direction.

This one really blows my mind... How can it get fuel like that? How can it survive that? What can I do to help?? Is it possible the piston rod is on backwards or something?? I have replaced all the internal components and the head and nothing has resolved this. TIA!
Old 11-02-2019, 08:15 AM
  #80  
1QwkSport2.5r
 
1QwkSport2.5r's Avatar
 
Join Date: Oct 2006
Location: Cottage Grove, MN
Posts: 10,029
Received 27 Likes on 27 Posts
Default

Originally Posted by tooth-pick View Post
So I have one of these on an OLD Ace Bingo 60. I have never managed to keep it running for a whole flight. However my problem is REALLY strange and I've found no reference online to it. Problem is, the engine always wants to run BACKWARDS! 80% of the time, flipping it with chicken stick, it fires and immediately changes direction and actually runs perfectly normal in the clockwise direction. However, I fear this could pose a problem with the flight aerodynamics!!! When it is running forwards, it will usually violently and instantaneously reverse with no sputtering or anything besides a loud crack like a gunshot from the physics defying abrupt reversal. This even happens at full throttle during flight and of course always shoots the prop nut off like a bullet. At lower speeds, it will reverse while humming perfectly at steady RPM and, if the prop stays on, will continue to run at the same RPM in the backwards direction.

This one really blows my mind... How can it get fuel like that? How can it survive that? What can I do to help?? Is it possible the piston rod is on backwards or something?? I have replaced all the internal components and the head and nothing has resolved this. TIA!
Engines that start backwards (clockwise) or reverse direction at a low rpm, are most often over-primed or too rich on the low speed mixture, or both. I have a dozen Sportsters. The only ones I’ve ever had a problem with low speed carburetion were with the carbs that came on my Target Drone engines - they were not machined to idle.

The only way one of these engines could run equally as well in either direction would require them to be piston ported/reed valve inducted. Rotary valves engines such as the Sportster and nearly most other sport engines, will only run one direction well due to the timing of the inlet port in the crank.
Old 11-05-2019, 10:18 AM
  #81  
carlgrover
 
Join Date: Jan 2002
Location: Decatur, AL
Posts: 763
Likes: 0
Received 10 Likes on 9 Posts
Default

Originally Posted by tooth-pick View Post
So I have one of these on an OLD Ace Bingo 60. I have never managed to keep it running for a whole flight. However my problem is REALLY strange and I've found no reference online to it. Problem is, the engine always wants to run BACKWARDS! 80% of the time, flipping it with chicken stick, it fires and immediately changes direction and actually runs perfectly normal in the clockwise direction. However, I fear this could pose a problem with the flight aerodynamics!!! When it is running forwards, it will usually violently and instantaneously reverse with no sputtering or anything besides a loud crack like a gunshot from the physics defying abrupt reversal. This even happens at full throttle during flight and of course always shoots the prop nut off like a bullet. At lower speeds, it will reverse while humming perfectly at steady RPM and, if the prop stays on, will continue to run at the same RPM in the backwards direction.

This one really blows my mind... How can it get fuel like that? How can it survive that? What can I do to help?? Is it possible the piston rod is on backwards or something?? I have replaced all the internal components and the head and nothing has resolved this. TIA!
Pull the pressure line off the muffler and let it dangle. You will have an entirely different engine. Never run muffler pressure with a sportster.


You're welcome,

carl
Old 11-05-2019, 01:20 PM
  #82  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 4,821
Likes: 0
Received 25 Likes on 24 Posts
Default

Originally Posted by woodburner View Post
Having a real hard time starting this thing... sometimes it starts and runs like a charm, sometimes it doesn't even hint at firing.... I'm running straight 0/20 FAI fuel on a OS 6 plug.

first thing first, WRONG PLUG !!, the OS 6 IS the wrong plug!! you need a long reach plug!! Hot yes.
can we get a photo of the engine? .what size prop?

Jim

Last edited by the Wasp; 11-05-2019 at 01:39 PM.
Old 11-05-2019, 01:33 PM
  #83  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 4,821
Likes: 0
Received 25 Likes on 24 Posts
Default

Here's my 100,
Old 11-14-2019, 05:26 AM
  #84  
1QwkSport2.5r
 
1QwkSport2.5r's Avatar
 
Join Date: Oct 2006
Location: Cottage Grove, MN
Posts: 10,029
Received 27 Likes on 27 Posts
Default

Originally Posted by the Wasp View Post
Here's my 100,
The K&B 1.00 is a completely different animal to the Sportster. Worlds apart.

I use McCoy MC59 plugs in all of my Sportsters. I have used Enya 3 plugs in a pinch (theyre hotter than OS 8 and F plugs), but as mentioned; the OS and Enya plugs are like a mid reach plug. Longer than a short plug but shorter than a long plug. As long as the plug is HOT and the fuel is right, they take whatever I can throw at them. DO keep the nitro to a minimum. They don’t need any, but 5% nitro does give a better idle and a little wider tuning window on the needle.

The mixture disc is very sensitive - centered is the base setting - use micro adjustments to get a good setting. Counterclockwise goes richer and clockwise leaner.

My current stash of Sportsters consists of a pair of .20s, a pair of .28s, a pair of .45s and three .65s. One each of these are new and unrun old stock engines. None have brass bushing in the crankshaft bore.

Last edited by 1QwkSport2.5r; 11-14-2019 at 05:29 AM.
Old 11-15-2019, 06:39 PM
  #85  
the Wasp
My Feedback: (1)
 
Join Date: Sep 2003
Location: VT
Posts: 4,821
Likes: 0
Received 25 Likes on 24 Posts
Default

he is running straight Methanol, maybe he needs even a hotter plug, maybe it's a bit too lean on the idle screw, maybe both. maybe he needs a larger prop that loads the engine more, seen that before more than once.

I just posted my 100 to show it, never the less it's the prop version not the duct fan engine

Jim
Old 11-16-2019, 03:43 PM
  #86  
1QwkSport2.5r
 
1QwkSport2.5r's Avatar
 
Join Date: Oct 2006
Location: Cottage Grove, MN
Posts: 10,029
Received 27 Likes on 27 Posts
Default

I run 80/25 in mine from time to time and the MC59 works fine even on that fuel. If the engine isn’t running correctly even with this plug and FAI fuel, I’d be ensuring a) the fuel mixture is on the fat side. B) prop load would be 1” more than typical for that size engine (at minimum), and I’d expect the compression to be really good. These engines are hard to ruin.

For the .20/.28 - a 10x6 is a good prop. For the .45 - an 11x7 or 12x6 is good, and the .65 - a 13x6 is perfect. Too much nitro or too small of a prop can cause problems - flameouts and unstable idle. Too much nitro will behave similar! Less than 10% nitro and 20-25% oil is best with the minimum being half castor. These engines MUST be treated like a 4-stroke!

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.