X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [64.12.143.101] (HELO imo-m13.mail.aol.com) by logan.com (CommuniGate Pro SMTP 5.2.7) with ESMTP id 3121268 for flyrotary@lancaironline.net; Tue, 09 Sep 2008 12:17:07 -0400 Received: from WRJJRS@aol.com by imo-m13.mx.aol.com (mail_out_v38_r10.8.) id q.ca2.3b2e4ca8 (37055) for ; Tue, 9 Sep 2008 12:17:03 -0400 (EDT) Received: from smtprly-da01.mx.aol.com (smtprly-da01.mx.aol.com [205.188.249.144]) by cia-db04.mx.aol.com (v121_r2.11) with ESMTP id MAILCIADB041-90bf48c6a17f1b2; Tue, 09 Sep 2008 12:17:03 -0400 Received: from webmail-dd06 (webmail-dd06.webmail.aol.com [205.188.104.6]) by smtprly-da01.mx.aol.com (v121_r2.12) with ESMTP id MAILSMTPRLYDA014-5bad48c6a17736b; Tue, 09 Sep 2008 12:16:55 -0400 References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: New rotary engine-mazda points on design Date: Tue, 09 Sep 2008 12:16:55 -0400 X-AOL-IP: 66.253.96.220 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: wrjjrs@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CAE0AE9C9F5F26_F78_10D6_webmail-dd06.sysops.aol.com" X-Mailer: AOL Webmail 38575-STANDARD Received: from 66.253.96.220 by webmail-dd06.sysops.aol.com (205.188.104.6) with HTTP (WebMailUI); Tue, 09 Sep 2008 12:16:55 -0400 Message-Id: <8CAE0AE9C87877A-F78-D6E@webmail-dd06.sysops.aol.com> X-Spam-Flag:NO ----------MB_8CAE0AE9C9F5F26_F78_10D6_webmail-dd06.sysops.aol.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii" Hey Guys, There is nothing wrong with the Bing Carb. The one Jabaru uses is a perfectly good carb, but tuning will effect any installation. Mikuni makes a vacuum carb that looks so similar to the Bing you can't tell the difference until you read the name on the side. Jabaru's intake system does not look optimized for power. Not really bad, rather super conservative and making carb placement easy. A carb of larger size or a better manifold?might certainly give better performance across the board. Port electronic fuel injection would probably be better, but the thing to remember that that system needs to be tuned as well. Bill Jepson -----Original Message----- From: George Lendich To: Rotary motors in aircraft Sent: Sat, 6 Sep 2008 6:45 pm Subject: [FlyRotary] Re: New rotary engine-mazda points on design ?That's good feed back Ben. I have myself suggested the Bing selection is not?such a?good one. I believe that some use Mikuni carbs as a replacement. I also notice with the Jabiru supplied Bing there is no leaning knob, perhaps their afraid of losing valves. The Jabiru supplied carb kit was running very rich mixtures and only recently have they offered replacement (and leaner) jets as a modification. ? I've flown a 4 seat Jabiru and the six cylinder is very strong and very good climb performance.?However I agree with the advice and so glad my opinion is supported. However some claim the benefit of altitude compensation, but I believe that's only good up to certain heights. ? I have been lucky enough to have recently worked on a RV 7 with the Bendix type ( constant feed) fuel injection system - only 30 psi. It looks simple enough and runs of a mechanical pump - can be run off an electric pump as well, so I'm told. ? Thanks again for the comment. George?(down under) George, A friend of mine is flying his Kitfox with a Jabiru 2200. He had some trouble with his carburetor leaking and took it to the FBO. The guy looked at it and told him they used to run the Bing carburetor?on motorcyles years ago and now throw them in the scrap pile. I think the Jab is a great engine, however, EFI would make it sing like your Suzuki. Ben ? ? ----- Original Message ----- From: George Lendich To: Rotary motors in aircraft Sent: Saturday, September 06, 2008 5:50 PM Subject: [FlyRotary] Re: New rotary engine-mazda points on design Tracy, I must be missing a point somewhere, or we have crossed wires, as I haven't mentioned the combustion chamber. My only concern is high pressure fuel leak in flight. Don't get me wrong I like fuel injection because of the control over injection volume and performance. I only wish there was high pressure at the point of injection -?only. ? I have fuel injection on my Suzuki 1800 Motorbike and it's great, but I would hate to have to work on it, like I did on the old carbied bike. ? I've noticed the Jabiru are running a very simple system. Their using a Honda ignition module with an altitude compensating carby?- not that the system is perfect either. George ( down under) ----------MB_8CAE0AE9C9F5F26_F78_10D6_webmail-dd06.sysops.aol.com Content-Transfer-Encoding: 7bit Content-Type: text/html; charset="us-ascii" Hey Guys,
There is nothing wrong with the Bing Carb. The one Jabaru uses is a perfectly good carb, but tuning will effect any installation. Mikuni makes a vacuum carb that looks so similar to the Bing you can't tell the difference until you read the name on the side. Jabaru's intake system does not look optimized for power. Not really bad, rather super conservative and making carb placement easy. A carb of larger size or a better manifold might certainly give better performance across the board. Port electronic fuel injection would probably be better, but the thing to remember that that system needs to be tuned as well.
Bill Jepson


-----Original Message-----
From: George Lendich <lendich@optusnet.com.au>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Sat, 6 Sep 2008 6:45 pm
Subject: [FlyRotary] Re: New rotary engine-mazda points on design

 That's good feed back Ben. I have myself suggested the Bing selection is not such a good one. I believe that some use Mikuni carbs as a replacement. I also notice with the Jabiru supplied Bing there is no leaning knob, perhaps their afraid of losing valves. The Jabiru supplied carb kit was running very rich mixtures and only recently have they offered replacement (and leaner) jets as a modification.
 
I've flown a 4 seat Jabiru and the six cylinder is very strong and very good climb performance. However I agree with the advice and so glad my opinion is supported. However some claim the benefit of altitude compensation, but I believe that's only good up to certain heights.
 
I have been lucky enough to have recently worked on a RV 7 with the Bendix type ( constant feed) fuel injection system - only 30 psi. It looks simple enough and runs of a mechanical pump - can be run off an electric pump as well, so I'm told.
 
Thanks again for the comment.
George (down under)
George,
A friend of mine is flying his Kitfox with a Jabiru 2200. He had some trouble with his carburetor leaking and took it to the FBO. The guy looked at it and told him they used to run the Bing carburetor on motorcyles years ago and now throw them in the scrap pile. I think the Jab is a great engine, however, EFI would make it sing like your Suzuki.
Ben
 
 
----- Original Message -----
Sent: Saturday, September 06, 2008 5:50 PM
Subject: [FlyRotary] Re: New rotary engine-mazda points on design

Tracy,
I must be missing a point somewhere, or we have crossed wires, as I haven't mentioned the combustion chamber. My only concern is high pressure fuel leak in flight. Don't get me wrong I like fuel injection because of the control over injection volume and performance. I only wish there was high pressure at the point of injection - only.
 
I have fuel injection on my Suzuki 1800 Motorbike and it's great, but I would hate to have to work on it, like I did on the old carbied bike.
 
I've noticed the Jabiru are running a very simple system. Their using a Honda ignition module with an altitude compensating carby - not that the system is perfect either.
George ( down under)
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