X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp0.av-mx.com ([137.118.16.56] verified) by logan.com (CommuniGate Pro SMTP 5.3.8) with ESMTP id 4366741 for flyrotary@lancaironline.net; Tue, 22 Jun 2010 13:43:04 -0400 Received-SPF: pass receiver=logan.com; client-ip=137.118.16.56; envelope-from=res12@fairpoint.net Received: from main (unknown [209.105.170.154]) (Authenticated sender: res12@fairpoint.net) by smtp0.av-mx.com (Postfix) with ESMTP id 4F8A81BFF6F for ; Tue, 22 Jun 2010 13:42:27 -0400 (EDT) Message-ID: <58FF3B4164DB44F3A3B686EEAA0632D9@main> From: "Richard Sohn" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Peripheral Port 13B Rotary Engine Date: Tue, 22 Jun 2010 12:42:57 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0081_01CB1208.70FF9EF0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5931 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5931 This is a multi-part message in MIME format. ------=_NextPart_000_0081_01CB1208.70FF9EF0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable The Mikuni VM series, as most any slide throttle carbs do not have a = venture throat. The throat size changes with the slide setting. Mixture = is maintained with different components at different slide opening. = These are, idle jet-needle with jet-main jet. Also, the shape of the = slide opening is contributing to throttle response. See Mikuni web sites for details. Complicated function with simple mechanics. Richard Sohn N2071U ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Tuesday, June 22, 2010 4:00 AM Subject: [FlyRotary] Re: Peripheral Port 13B Rotary Engine Thanks Richard, That's interesting! Did you have a choke or reduction in throat size = in the 38mm carbie, and does the Mikuni have a venturi throat George (down under) George, I had focused on the 38mm and was doing pretty good with it, until I = realized I could not maintain a good mixture over the whole operating = range. Obviously, that is why the specification says it is good for up = to 65hp.=20 Even so the carb is 44mm now, my intake runner is still 38mm = maintaining the intake tuning. Richard Sohn N2071U ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Monday, June 21, 2010 4:59 PM Subject: [FlyRotary] Re: Peripheral Port 13B Rotary Engine Richard, Ah The magic 44mm. I know you are running a 12A but at what rpm = are you running out of breathing, provided you have had the single that = high. I would have to run the numbers but thought you would get away = with a 38/40mm carb and push up the velocity.=20 George (down under), this flywheel is my design, it is steel with the cut outs for = balancing. The steel section is 14mm thick, and the ring gear is 250mm = diameter, coming off a Metro Geo engine.=20 I calculated my hp from fuel flow using a BFSC of .5 . May be a = little optimistic. Mixture was slightly rich at the tests.=20 I am running now a Mikuni VM44 carb. Richard Sohn N2071U ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Monday, June 21, 2010 3:39 AM Subject: [FlyRotary] Re: Peripheral Port 13B Rotary Engine Richard,=20 We seem to be singing from the same sheet of music in regard = to projected HP at RPM, at optimum performance. So what weight have you = got on that flywheel, it seems to be a cut down manual cast flywheel = from a past photo. I figured I might need a heavier flywheel than the = flexplate and was considering having one of those aftermarket steel ones = made and have mounting holes included to suite what ever damper I = incorporate. BTW this is single rotor specific if anyone was confused. George (down under) Is anyone flying with a Mazda 13B peripheral port engine? = If so, how is it working? Can you describe the advantages and = disadvantages? =20 Thanks, =20 Bob Rogers ------=_NextPart_000_0081_01CB1208.70FF9EF0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
The Mikuni VM series, as most any slide = throttle carbs do not have a venture throat. The throat size = changes with=20 the slide setting. Mixture is maintained with different components at = different=20 slide opening. These are, idle jet-needle with jet-main jet. Also, the = shape of=20 the slide opening is contributing to throttle response.
See Mikuni web sites for = details.
 
Complicated function with simple=20 mechanics.
 
Richard Sohn
N2071U
 
----- Original Message -----
From:=20 George=20 Lendich
Sent: Tuesday, June 22, 2010 = 4:00=20 AM
Subject: [FlyRotary] Re: = Peripheral Port=20 13B Rotary Engine

 Thanks Richard,
That's interesting! Did you have a = choke or=20 reduction in throat size in the 38mm carbie, and does the Mikuni = have a=20 venturi throat
George (down under)
George,
 
I had focused on the 38mm and was = doing pretty=20 good with it, until I realized I could not maintain a good mixture = over the=20 whole operating range. Obviously, that is why the specification says = it is=20 good for up to 65hp.
Even so the carb=20 is 44mm now, my intake runner is still 38mm maintaining the intake=20 tuning.
 
Richard Sohn
N2071U
----- Original Message ----- =
From:=20 George=20 Lendich
To: Rotary motors in = aircraft=20
Sent: Monday, June 21, 2010 = 4:59=20 PM
Subject: [FlyRotary] Re: = Peripheral=20 Port 13B Rotary Engine

 
Richard,
Ah The magic 44mm. I know you = are running=20 a 12A but at what rpm are you running out of breathing, provided = you=20 have had the single that high. I would have to run the = numbers but=20 thought you would get away with a 38/40mm carb and push up the=20 velocity. 
George (down = under),
 
this flywheel is my design, it = is steel=20 with the cut outs for balancing. The steel section is 14mm = thick, and=20 the ring gear is 250mm diameter, coming off a Metro Geo = engine.=20
I calculated my hp from fuel = flow using a=20 BFSC of .5 . May be a little optimistic. Mixture was slightly = rich at=20 the tests.
I am running now a Mikuni VM44=20 carb.
 
Richard Sohn
N2071U
 
 
----- Original Message ----- =
From:=20 George Lendich
To: Rotary motors in=20 aircraft
Sent: Monday, June 21, = 2010 3:39=20 AM
Subject: [FlyRotary] = Re:=20 Peripheral Port 13B Rotary Engine

 Richard,
We seem to be singing from = the same sheet=20 of music in regard to projected HP at RPM, at optimum = performance. So=20 what weight have you got on that flywheel, it seems to be a = cut down=20 manual cast flywheel from a past photo. I figured I might need = a=20 heavier flywheel than the flexplate and was considering having = one of=20 those aftermarket steel ones made and have mounting holes = included to=20 suite what ever damper I incorporate.
BTW this is single rotor = specific if=20 anyone was confused.
George (down = under)
Is anyone=20 flying with a Mazda 13B peripheral port engine?  If so, how is it=20 working?  Can = you=20 describe the advantages and=20 disadvantages?

 

Thanks,

 

Bob=20 = Rogers

= ------=_NextPart_000_0081_01CB1208.70FF9EF0--