Multiply tries with wrong choke settings and flat battery can ruin your day. This happened yesterday.

Technically speaking,  the Bing 54 doesn't have a true choke/throttle plate that restricts incoming air volume,  it has an "enrichment system" which adds extra fuel.

The 084 has a true choke, not an "enricher" like most of the 2 cycles have..

When the choke is open it still has the flapper and rod across the intake of the carb..SO I removed mine completely so it could get more air into the carb. The air intake of the carb is approx. the same size as one of the tubes that go to the cylinders and there are four of them.. So I thought that anything to let in more air couldn't hurt..............

As of today:
Starter motor was not running with the flywheel- fixed, battery charge - fixed , ignition timing - fixed. Motor runs.
The alignment of the redrive belt is very sensitive, 1 mm washer at the top or the bottom makes the belt slip off either to forward or back. Either a tensioner/limiter will be installed but Iam really looking for alternatives to the cog belt to poly v belt, possibly redo the pulleys to PK shaped automotive belts.  
I still can revert to direct drive within 10 minutes, but once you tasted it with redrive its better.

I'm almost positive the "choke" on the 4A084 operates on the same principal as my 2A042 carb, and most "old time" carburetors for that matter. The choke butterfly is at the opening of the carburetor. When the butterfly is closed, the air restriction increases the vaccum signal to the carb's jets and that sucks in more fuel than it would without the choke butterfly restricting the airflow and increasing the vaccum.

As I understand an enrichner circuit, like that on a Bing carb, it opens an additional fuel passage and additional fuel can be drawn in through that passage. That circuit is open to the "downstream" side of the carb's throttle slide. For the enrichener circuit  to really operate though, the throttle must be closed, or very close to being closed, since it relies on a strong vaccum signal on the "downstream" side of the carb's slide. If the throttle is open very far there's not enough air restriction through the carb to create a strong vaccum signal at low starting and/or idle RPM to pull the extra fuel into the airstream.

In a way, they both operate somewhat the same. The choke restricts airflow, creating vaccum in the carb, which pulls additional fuel through the regular jets. The enrichner is an additional fuel circuit which allows extra fuel to be drawn in, but it's still using vaccum downstream of the throttle slide to do it.

I hope this helps   I tried.

Lynn

Hey TTT;
Harless and Lynn got it right on. Tom, I mean this light heartedly, I think you should read a little more.
Bob

Done had one bag....... Wanna open another?  

Quoted from Harless Greear

...When the choke is open it still has the flapper and rod across the intake of the carb..SO I removed mine completely so it could get more air into the carb. The air intake of the carb is approx. the same size as one of the tubes that go to the cylinders and there are four of them.. So I thought that anything to let in more air couldn't hurt..............

Yes and no here... each cylinder is not pulling air all the time, only when the valve is open.  If you check the cam timing for the intake valve you will likely find on a 4 cylinder engine that there is no more than one cylinder pulling air at a time with gaps between.

But you are otherwise on the right track.  The engine is an air pump and power is dependent on how much air can get through the cylinder and more air is always more power.  On the exhaust side we have very high pressure to push that air through/out.  On the intake side we only have 14.7 PSI at sea level making the intake much more sensitive to improvement than the exhaust.

Some hot rod types have been known to airfoil the throttle butterfly plates and shafts for this reason.  Most aircraft intakes and carbs are awful air handlers (lots of sharp bends) and the improvement from airfoil or elimination of shafts is zero because of the other limits in the intake system.

Also like airplanes come in two types (fighters and targets) so do carbs: fixed venturi and variable venturi.  The Bings are variable venturi and "old" carbs are fixed venturi.  Fixed venturi carb --> second shaft/blade as choke and variable venturi carb --> extra enrichment fuel circuit.  Lots of fun stuff happens from there...

Sometimes I am completely amazed and impressed at some of the engineering and solutions people have come up with and carb design and operation is one of those almost magical devices.

The 084 stock carb works very well.  
Carb heat does help a bit, and I will be testing ram air intake late spring as weather will allow.

Pkoszegi, if you are talking about having trouble getting the correct choke setting to start the engine you might try this the next time: flood the engine
turn the fuel off
throttle full open
crank the engine until it starts to run on the fuel in the cylinder(s)
turn the fuel back on as soon as the engine begins to fire.

If you have spark, when the mixture gets correct the engine will start.

I am not familiar with your engine at all! but this procedure has worked on carbureted engines from 2 hp. to 450 hp. and has proven to be the surest procedure to hot start fuel injected aircraft engines. That was using mixture control to turn off the fuel, so there was no concern about fuel in the lines or anything like that. Come to think of it, the smallest engines were on lawn mowers that sat through the winter.

No starter on one's engine (hand propping) tends to improve one's memory of procedures that work.

Using a primer instead of a choke will not help with carb icing. I have never flown an aircraft engine with a choke and all of the 4 strokers were subject to carb ice when the temperature was right. Somehow, 98% or more of my flying has been where the humidity was always high so the variable has been temp.

Hope this helps should you need it, but hope you never have to find out.

Bert,
Now its sorted out, so far I clocked 50 hours or so in this 084.
But when you put a freshly overhauled engine where all things are taken apart and put it back it requires a bit more than simple procedures of starting.
Once the battery is charged (or you are prepared for  hand propping) and the starter motor and its flywheel alignment is good, and your ignition time is correct, so as your carb settings its a piece of cake to start the 084.
It starts very easy. Full choke, fully open throttle, no mags. 2-3 full turns, throttle back to idle, choke off, mags on and it cranks with no problem.

But a few tries with incorrect settings and you dont know if you flood the engine, plus the battery runs flat, and the starter moves off the flywheel it all comes to one annoying big pile of failure.
Plus adding a -5 C degree  (23F) is really a trying moment of your patience .

Now its all done and it works like a swiss clock.

Now I am about to fiddle with the redrive pulley alignment. Temp today hits as low 14 F.
Peter

Run in with direct prop and instrument testing:
https://www.youtube.com/watch?v=mVF_417Wd7o&list=UUFUev9XOLR_zH0QZyIwiSxA

The engine overhauled, run, the redrive was redone with microbelt PK, alignment is set, the upper pulley runs in ATP oil, Bob was a great help to fix that.
I made a couple of takeoff and about an hour flight time already. Works Great.
The carbheat is a good option. It works very well in cold weather.

Sweet!!    

Beautiful Hi-Max !

Here that goes with sound:
https://www.youtube.com/watch?v=l2n6AMx7CsA&feature=youtu.be

Very nice plane Peter! Congratulations.

Is  the take off distance around 150 mts (500')?

Quoted from Ricardo

Very nice plane Peter! Congratulations.

Is  the take off distance around 150 mts (500')?

Actually its about 70-80 meters. The same as other Himax. Climb is a bit  sluggish, but at 500 meters (1500 ft) from brake release its at 100 meters (300 ft).

Way to go Peter! It looks like your having fun.

Quoted from pkoszegi

Climb is a bit  sluggish, but at 500 meters (1500 ft) from brake release its at 100 meters (300 ft).

That's not too bad.  The first 75'-100' is most important,  to clear trees, powerlines, etc.

Love that sound.

Some of you asked me about reinforcements. Apart of the firewall and the cabana struts I dont know any specials in the wings. But one thing I feel is very important if you install this relatively "heavy" engine. You must have a nice flex landing gear, either from alu spring or from composite, or any sort of dumper. That can absorb those very heavy loads and stress during takeoff and landings. If you guys are in the US, Georges composite gear looks like the one under the fuselage.  
That needs some more thinking on "what if I install this engine in a Minimax".

Regarding the reduction drive, I had some learning curves, but now I have a good solution which is not very heavy. Redrive has a very positive effect on performance, and suprisingly no dramatic effect on cruising RPM.

I have a video of my take off that I use for comparing other planes take off performance ,  its 15 seconds long, The camera starts  when the throttle is open. the take off occurs at 6 second and at 15 seconds is passing the camera that is at about 700 feet mark with a 100 feet altitude.
Your video starts the same way as the throttle opens yet it doesn't even leave the ground until after 15 seconds, that ground roll must be at least 700 feet long
See what I'm talking about here
https://www.youtube.com/watch?v=mivvHQ_wpWQ

Hi George
You neglected to tell us what your plane weighs.
Bob

Playing forensic science or NTSB:
Below is the map the airport. The elevation of starting point is 207m AMSL   the other end of the airport 450 m and its 221m AMSL so uphill start.
The video was made at 3.30 pm. I marked the shadow of the windsack on the map. There was a slight crosswind on that day you may check it in weather history , but its basically 0 headwind at the time of recording. (but also see the shadow of the sock)
The static max RPM of the plane is curently set to 3250 engine rpm. Cruising is 110 km/h at somewhat 2800 rpm. So the prop is set to cruise performance. Its a fresh engine, fresh redrive so I dont do STOL takeoffs currently and I am light on throttle. I dont push this into the limits in the first hours.
The plane does not have wheel pants neither drooped wingtip. That means a lot reducing inducted drag at the time of takeoff.

Taking all that effect, measured more accurately the takeoff distance currently is 90 m. Which is 270 ft. Which is very very far from 700ft long as you guessed badly. However, next time George, compare weight, and get some more clear videos, since your ground roll can hardly seen, only when you have enough speed to put the stick on your stomach. Also it would be nice to see some headwind reference on your vid.

If I put my hoerner wingtips on this plane, plus let the static engine rpmfrom 3250  to 3500, I can really do whatever I want. Plus I can wait for some more headwind and show vertical liftoff but that would be a trick.

Some more:
https://www.youtube.com/watch?v=cQEmL436ZmM&feature=youtu.be

Thats 90 meters. (297 ft)   Red dot is the camera position.

Here are some photos from yesterday just for the record. I added 1-1 hour into each of them.
4a084 is a very very good engine. Fairly simple installation, its been tried out. Performance of the two does not soar too much pretty much even. I can only say good things. If you dont want to spend money on old two stroke engines, I can only recommend. YOu may go light as 123lb without starter/flywheel, direct drive or you go after luxury with starter flywheel, redrive and an exhaust muffler and you have no comparison with other aircrafts.

More

The yellow one looks like a tiny Cub.  

We had exceptional high summer temperatures reaching 100F. That sort of heat and thin air made the oil temp going up to 200 F.  However the oil is graded for that temperature (20W50 Racing)
but I installed an oil cooler. Now its cold, so I cant tell you whats the result. But it should work.
I dont know where are these coolers originally from, Bob sent me these and I used them.