AmishWarlord

My Feedback: (5)

This is a club for the Sportster line of K&B engines and the models that are powered by them.

I'll be adding info to the post below. So check back to this page.


General characteristics of a K&B Sportster engines

That all have the same crank shaft size. 1/4"-28 TPI

Most people who run these engines state that they like to run on a high level of caster oil "25%" in the fuel and that synthetic fuels cause problems.

The timing of these engines make it so that they do not like to run well at high RPM.
You should treat these engines more like a 4-stroke or Diesel, as in they like to swing larger props at slower speeds.


No Sea Plane, flown with a K&B Sportster, has ever had rusty ball bearings in the engine.

AmishWarlord

My Feedback: (5)

K&B Sportster .20

Where to buy new. https://shop.mecoa.com/shopdisplayproducts.asp?id=22

Start prop, 9x4

Fuel tank size 4 oz.

Fuel 5% Nitro, 25% caster

Glow Plug, standard Long Reach Glow Plug

Carb size .199 ID .437 OD

Owners guide
http://www.mecoa.com/kb/56/5600.htm

Parts

Accsessories

Muffler Gaskets, ebay larrybtoys http://www.ebay.com/itm/K-B-Sportste...-/320707403168

Perry Carbarator #3701 Standard carb http://www.perrypumps.com/

Fuel Regulator Iorn Bay http://www.ironbaymodelcompany.com/i...es/Page438.htm

AmishWarlord

My Feedback: (5)

K&B Sportster .28

Start prop, 9x4

Fuel tank size, 6 oz.

Fuel, 5% Nitro 25% caster

Glow plug, standard Long Reach Glow Plug

Carb size .248 ID .437 OD

Owners guide,
http://www.mecoa.com/kb/56/5680.htm

New Engines
https://shop.mecoa.com/shopdisplayproducts.asp?id=22

Accessories

Carb,

Perry Carb, #2100
http://www.perrypumps.com/prod01.htm

Fuel Regulator,
http://www.ironbaymodelcompany.com/i...es/Page438.htm


J-Tec mufflers
Custom made
http://www.jtecrc.com/incowlmufflers10-39.htm


Bission mufflers

Pitts,
http://www.bissonmufflers.com/en/muf...ting_id=113959

Sport
http://www.bissonmufflers.com/en/muf...ting_id=113960

Quite Sport
http://www.bissonmufflers.com/en/muf...ting_id=113961

Upright
http://www.bissonmufflers.com/en/muf...ting_id=113962

Inverted
http://www.bissonmufflers.com/en/muf...ting_id=113963

Tru-Turn Spinners
Adapter TT-0140-A
1/4-28 ADP Kit With 1/4" Bushing
http://www.truturn.com/cgi-bin/store...0a&ppinc=adapt

AmishWarlord

My Feedback: (5)

K&B Sportster .45

Start prop 10x6

Fuel tank size 8 to 10 oz.

Fuel 5% Nitro 25% caster

Glow plug, standard long glow plug

Carb size .270 ID .530 OD

Owners guide
http://www.mecoa.com/kb/59/5900.htm

New Engines
MECOA
https://shop.mecoa.com/shopdisplayproducts.asp?id=22

Parts

Accessories

Perry Carbs,
Standard #2600
Pump #9300
http://www.perrypumps.com/prod01.htm

Fuel management,

VP-30 Regulating pump for use with pump carbs
http://www.perrypumps.com/prod02.htm

Iron Bay Fuel Regulator for non-pump carbs
http://www.ironbaymodelcompany.com/i...es/Page438.htm


Slimline pitts muffler, #3513
http://www.slimlineproducts.com/pk4/store.pl?section=91

Bisson Muffler #11048
http://www.bissonmufflers.com/en/muf...ting_id=113999

Macs Mufflers
.40 Size Adapter Muffler #6400
Adapter Plate #6548
http://www.macspro.com/onepiece.asp

Macs Headers
Standard 2540
Long 2541
Ex-long 2542
15° marine 2543
http://www.macspro.com/headers_side.asp


On Board Glow Hobby King
http://www.hobbyking.com/hobbyking/s...dproduct=15517


Tru-Turn Spinners
Adapter TT-0140-A
1/4-28 ADP Kit With 1/4" Bushing
http://www.truturn.com/cgi-bin/store...0a&ppinc=adapt

AmishWarlord

My Feedback: (5)

K&B Sportster .65

Start prop 11x7

Fuel tank size, 12 to 16 oz.

Fuel, 5% Nitro 25% caster

Glow plug, standard Long Reach Glow Plug

Carb size .340 ID .625 OD

Owners guide
http://www.mecoa.com/kb/58/5800.htm


New Engines,
MECOA
https://shop.mecoa.com/shopdisplayproducts.asp?id=22

Carbs,

Perry Carbs
Standard Carb 4600
Pump Carb 9600
http://www.perrypumps.com/prod01.htm#kb

Fuel management,

VP-30 Regulating pump for use with pump carbs
http://www.perrypumps.com/prod02.htm

Iron Bay Fuel Regulator for non-pump carbs
http://www.ironbaymodelcompany.com/i...es/Page438.htm


Spinner adapters,

Tru-Turn
TT-0140-A
1/4-28 ADP Kit With 1/4" Bushing
http://www.truturn.com/cgi-bin/store...0a&ppinc=adapt

Mufflers,

Bission
.65 Pitts #11061
http://www.bissonmufflers.com/en/muf...ting_id=114000
.65 Sport #11062
http://www.bissonmufflers.com/en/muf...ting_id=114001


Macs
One Piece Mufflers
http://www.macspro.com/onepiece.asp
.60 size Adapter Muffler #6700
Adapter Plate #6788

Macs Tuned Pipe Headers
http://www.macspro.com/headers_side.asp
Standard 2780
Long 2781
Ex-long 2782
15° marine 2783


Slimline
Pitts #3112
Invert or Upright #3102
http://www.slimlineproducts.com/pk4/store.pl?section=92

On Board Glow Hobby King
http://www.hobbyking.com/hobbyking/s...dproduct=15517

flyingagin

Thanks Amish
I have owned 2 .20s and 2 .45s. Presently own a .65. Wish I still had the previous 4 engines.
Good running engines if treated correctly. They are made a little different and so need to be treated the same.
Just so others know they like oil. They also need a goodly amount of castor oil in the mix. Give 'em what they want and they will go forever.
So here is an earlier pic of my plane sporting a sportster. The plane is still under construction and will keep the .65 sportster.
Amish, I bet you reconize this plane. I will have to slap the engine back on for some pics now that it has some paint.

turbo.gst

My Feedback: (8)

Big time Sportster fan here! I have at least one of each size. The oldest, a 65, was bought in 1987( it has no bronze bushing and an O-ring head gasket). I have yet to wear one out.

1QwkSport2.5r

I currently have 2 Sportster .65's from the Goldberg Mig-27 Army Drone foamies. They have bad carbs so I'm in search of new ones that actually work. Mine were made in 1990 or so, and have no head gasket. Metal to Metal head, and no bronze bushings either.

I am keeping my eyes open for a .20, .28, and a .45 so I can have at least 1 of each size. I'll only buy these engines New as most people dont run castor fuel in them and ruin them.

I'm a big fan of the Sportster engines as well. No planes to speak of just yet... but that will change with time. I love the sound they make.

flyingagin

I think many people thought poorly of them, but it was simply a lack of knowledge. The right kinds of oil and right amount, make all the defference.
I prop them more like a 4 stroke. And the fuel burn is very low compared to other 2 strokes. I have had my .65 go for more than 30 minutes on 1 tank (16 ounce) of fuel doing touch and go practice.
For oil I go for 22% with 1/2 being castor.

flyingagin

You got that right.

1QwkSport2.5r

I was running mine on 5% nitro 20% oil SIG champion (oil is 50/50 cas/syn) but I have since converted to ALL castor in ALL of my engines. My sportsters get 5% nitro 25% castor, but they still dont idle or transition for poo. I quit using muffler pressure which gave better rpm but still a lousy idle (wont idle) and horrible transition (rich).... Grr..

If anyone has 2 good/working carbs that will fit the .65 (.622" neck) I will buy them in a heartbeat.

1QwkSport2.5r

Thats the reason I dont have a .20, .28, or a .45 yet. I'm not much of a fan of Randy at Mecoa, so I'd rather buy engines from RCU members. Just waiting for some NIB engines to show up in the marketplace.

AmishWarlord

My Feedback: (5)

RCU is being a pain for me. It wont load, syays I posted to fast, says service unavalible, goes to web page not found. Grrrr

codycarlisle25

I think of mine as a poor mans 4 stroke. Fantastic! I have 8 Sportster 65's.

AmishWarlord

My Feedback: (5)

I put a link to the Perry carbs up there.

flyingagin

I have a couble of .60ish carbs, sans engines, I will check the neck size.

buzzard bait

So what's the plane with the .65?

I liked my .20 on the test stand very much. Have not flown it yet. I used 22% oil, 1/2 castor, and broke it in with short rich runs, gradually getting leaner. It just got better and better. At the end, it would turn a 12x4 without any complaint.

And yes, the sound with the stock muffler is nice.

Jim

1QwkSport2.5r

If I wanted to spend $100 on a carb, I'd buy 2 new K&B carbs. I am not in a hurry, so I'm hoping to find 2 identical used carbs. Preferably SuperTigre carbs if they even make a carb with a .622" neck. Otherwise I'd take 2 OS carbs or if TT has a carb that fits. Perry is a last resort... If by May I havent found anything, I'll order 2 new carbs.


These Sportster .65's have unusually HUGE carb fittings.. The guy at my local plane/heli shop said something along the lines of "Holy crap thats huge!".

The base is .622" and the venturi is .334". A slightly bigger venturi doesnt bother me since the muffler extensions have pressure taps.

I compared my carb's internals (visually) to Hobbsy's Sportster .65 carb and they look identical. Supposedly the Drone engines have botched up carbs. Rumor has it a new Idle disk might fix my problems, but I'm not in the position to throw $40 into the wind since the Barrel might be part of the problem as well. A new barrel (and carb housing comes with the barrel as a set) and idle disk costs as much as a whole carb from Mecoa.

Edit: This forum is really getting aggravating with all the errors and timeouts. It took me almost a half hour to post this. For how much sponsorship this site gets, you'd think they'd be able to get their server problems sorted out a lot quicker than they are.

1QwkSport2.5r

Your sportster would be even happier if you fed it all castor and no synthetic. Mine turns 400rpm faster on all castor vs. SIG Champion which is 50/50 blend. Thats with 25% castor to boot.

The front bushing on my .65 doesnt spew nearly as much oil as it used to on SIG fuel.

turbo.gst

My Feedback: (8)

I run my 65 with a BCM low DB muffler. I have people come up to me and ask what I'm flying as it sounds more like a 4-stroke than anything. I tell them what it is and they have to see it after landing as they don't believe it. I put it on 45 sized aerobatic planes using the spider backplate soft mounted with a 13 x 5 prop. Great power and extended verticals without a lot of speed. The extra airflow over the control surfaces makes for some really smooth landings. I Really like it in that role!

buzzard bait

Very interesting. Only issue is how many different kinds of fuel I'm going to keep!

AmishWarlord

My Feedback: (5)

No kidding. Took me hours just to put up what little info I have up now.

Should have taken 45 mins.

earlwb

I happen to have four K&B .20 Sportster engines and a .65 Sportster engine too. I had originally planned to use the .20 engines on a Royal B-17 I was building but the framed up plane met its end when I was moving and got crushed in the process.

1QwkSport2.5r

I didnt want to have 10 different mixes, so I just run 2 standard mixes. (I make my own fuel). ALL airplane engines regardless of cylinder/piston construction is 5% nitro 20% castor minimum. My Sportsters and my Fox .40 (single BB) will get 25% castor and 5% nitro. My car engines (2 - .20's, a .26, and a .28 all ABC) get 20% nitro and 12% oil although I am going to test 8% oil and 10% oil tomorrow in the .26 and .28.

I got a funny look from one of my Airboat buddies last summer. "Your engine's exhaust smells weird" He's used to Omega, so of course it smelled funny.. haha.

1QwkSport2.5r

Would you consider selling one of your .20's or do you still have plans of flying all 4 of them?

edit: Also, your .65 has the big head fins on it. Must be an early model. Most of the newer-than-'90 engines have the short machined head fins.

edit #2 (while RCU will let me): Since this is a new club and I feel left out since I dont have a club member number in the Enya, Fox, or ST clubs... can I be #4 if we do member numbers? [8D] (I know it is of zero importance but I dont care.. lol)