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PostPosted: Mon Apr 16, 2007 10:00 pm
by daffy1029
I have installed 210cc Solo engines on my Lazair and would like to go with a float bowl type carb. I am familiar with jetting and setting up this type of carb, but I don't know enough about selecting carbs. Can I use carbs off motorbikes or snowmobiles? Any recommendations? Thanks, daffy

PostPosted: Wed Apr 18, 2007 4:37 am
by xgary
Daffy >> ?? CARBURETOR: WALBRO - Main Jet Cu) 7/8 turn open
Solo 210 engine service manual - engine operating specifications, page 1.



REDUCTION UNIT: 3-1 Ratio - Belt Type

PROPELLER: 54N x 27N Pitch (Wood)

ENGINE COOLING Thru Propeller only

MUFFLER: Tuned Exhaust

CARBURETOR: WALBRO - Main Jet Cu) 7/8 turn open

- Low Jet CL) 1-1/8 turn open

IDLE SPEED: 1500 RPM - rich setting

3800 RPM - 1500 C plug temp. 4 cycle

4000 RPM - 1650 C I' 2 and 4 cycle

4500 RPM - 1700 C N I. 2 and 4 cycle

5000 RPM - 1780 C " " - 2 cycle

5500 RPM - 1899 C " I' - 2 cycle

6000 RPM - 1970 C " I' - 2 cycle

6500 RPM - 2130 C " " - 2 cycle

7000 RPM full throttle)-2210 C plug temp. - 2 cycle


BREAKING-IN PERIOD: For the first three (3) hours of operation, a new engine should not be run at more than 1/2 to 3/4 throttle under load For the break-in period use 25:1 fuel oil mix. After breaking-in period ~se 30:1 fuel oil mix.


a) Close throttle.

B) Turn off ignition. The kill switch grounds the short circuit cable from the engine.

c) Close fuel valve.

PostPosted: Wed Apr 18, 2007 4:58 am
by xgary

one more thing is what do you not like the diaphram carbs > ?

The float ones do not like neg G and /or inverted -
I think the Walbro a better choice and simple too.

PostPosted: Wed Apr 18, 2007 5:21 am
by xgary
BING CARB info ?


Empty weight (unfueled): below 20 kg (depending on version)
Total weight (fueled): 28.0 kg

Type of engine: SOLO, Germany (two stroke engine)
Number of cylinders: one cylinder, air cooled
Cubic capacity: 220 ccm
Engine power: 18 h.p.
Carburator: BING 32mm type 84
Sparkling plug: BOSCH W 5 AC
Ignition system: electronic (transistor)
Starter system: by hand (starter rope) or electric
Muffler system: two step resonance muffler
(development by Fresh Breeze)

Propeller: two blade
Propeller diameter: 110 cm (122 cm version available)
Propeller material: carbon fibre composite (very light)

Transmission: 1 : 2.95 rev. reduction
Type of transmission: Optibelt multi V-Belt (8 PK 725)

Mainly used material: aluminium (for weight reasons)

The used SOLO two stroke engine produces more power than the original
engine (original specification is 14 h.p.) due to the use of a special
muffler system which increases the power and reduces engine noise
at a given revolution. (resonance muffler system) As a result of the
higher engine power the engine cylinder had to be supplied with an
additional cooling, therefore a special cooling cylinder head had
to be mounted (see zoomed picture down this page).

The whole device can be ordered in different verions including
electronic starter, wood propeller or glass fibre composite propeller
(both a bit hevier than the carbon fibre composite propeller),
deployable safety cage (for car transportation). There are also fully
painted or the "luxury" chrome editions (see pictures down this page)
available at Fresh Breeze...

FRESH BREEZE, Hindenburgstr. 15, 30851 Langenhagen, GERMANY
Phone: (+49) 511 / 739846, Fax: (+49) 511 / 721860


PostPosted: Wed Apr 18, 2007 7:52 am
by daffy1029
Hi shortnaked,
Thanks for the reply, the biggest reason for wanting float bowl carb over pumper carb is to get rid of the primer bulbs. The primer bulbs are getting to be a hassle for me (rubbers don't last, they fail internally sometimes blocking the fuel flow) and are the weakest link in the fuel system. I have installed electric start on my Lazair and would like to be able to shut off the engines while in flight to practice emergency landings and to get a good feel, for engine off flights. With float bowl carbs, once the fuel is in the bowl, it will start without have to prime, just because the gas is right there. I found with the walbro carbs, I had to prime everytime in order to get it started. When flying, you don't want to be fiddling with primer bulbs and worrying about flooding the engines.
When the engines are running with Walbro carbs, they run great! But, I won't be doing any inverted flights or stunts with my plane, so pumper carbs aren't necessary for me. Oh, by the way, float bowl carbs are more efficient than pumper carbs.
I was even thinking using Mikuni carbs off a snowmobile with about 400cc and having two carbs. That would be about the right size for the Solo's, yes? I know they can take the vibrations and are good carbs.

PostPosted: Wed Apr 18, 2007 9:37 am
by xgary
Daffy you read the above post i made ?
>>>Carburator: BING 32mm type 84 <<

Now - i have never used a primer bulb yet on a 185 rotax.
I have bing 54s on my 582 and they are great and
simple - but to adjust high speed mixture you have to take apart and move high speed needles. Only twice a year for me.
But on the diaphragm carbs you just turn the high speed screw.

the Bings do not have chokes - they have enrichers which allows raw fuel directly in to carb as the pulse pump pumps fuel through it . A primer can be used as well that squirts fuel directly into back of carb but it not a primer bulbs.
You will also need a separate fuel pump as the bings do not have a fuel pump - imo just another thing to screw up times 2 engines.
I think the best thoughts are what ever works for you ........... plus KIS Keep it simple.


PostPosted: Wed Apr 18, 2007 8:36 pm
by lazairkid
:D Daffy,
Shorty is right on the Neg g's, Bings were not recommended to me ether.
I have Walbo 37c's on my solo 210s I have ran them for about 15 min but
they run smooth. I'm going to do more running this Sunday to fine tune the carbs and get the engines broke in.
I use a electric fuel pump to pump fuel to the carbs then shut it off
and let the carbs take over. I use a closed cell battery for the pump.
I only have to use the fuel pump for first start after that they start
every time with out the fuel pump.
Paragliders have these small Batteries that work.
Here is some Info for you I have.
Southernskies has all the up to date brake-in, fuel ratio, Castrol TTS oil
for the solo 210.

Hope this Helps

Alex Varv at Aerocorsair is a good source for info, he helped me with
the carbs.
I'll update you.

PostPosted: Thu Apr 19, 2007 9:21 am
by lazairkid
Pic two engines running

PostPosted: Thu Apr 19, 2007 3:51 pm
by xgary
Sweet setu p you got there.

Have you flown it yet ?

What kind of numbers you got ?

PostPosted: Thu Apr 19, 2007 4:51 pm
by lazairkid
:D Not yet Shorty,
I'm tuning the carbs and getting the brake-in done.
I well be doing taxi test on Sunday.
On two of my full power run ups it was all I could do to hold it back
one of the guys had to hold the tail boom.
I'll have to find a scale to hook up to the lazair and get a static