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<DIV><FONT face=Arial size=2>Hi Eric: A few months previous I tried to buy
an M/C carb for my OS 1.40"s. I was told they were no longer
available in NA,due to lack of denand.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I tried to buy one from Singapore,and just missed
their last one. Glad now I missed it as price was atrocious</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>About that time Webra arrived on the scene with
their M/C Carb,which seems to be quite popular.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>(1) Does OS perhaps
have plans to bring their MC Carb back to NA,at a reasonable price.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>(2) Will The Webra MC Carb fit
the OS Case,or be easily modified to do so?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Cheers,,,,,,,,,,,,,Dave</FONT></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=Eric.Henderson@gartner.com
href="mailto:Eric.Henderson@gartner.com">Henderson,Eric</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, January 22, 2004 12:32
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Tuning OS's</DIV>
<DIV><BR></DIV><!-- Converted from text/rtf format -->
<P><SPAN lang=en-us><FONT face=Arial>My time with the OS 1.40RX goes back to
1997/8 when I bought four of them and a tuned pipe from a small English hobby
shop, on one of my trips to the UK. Although I don't own the motors anymore I
know where they are. :-) The UK customs had a fit when they saw
the pipe on their x-ray machine... Just made the plane in
time...</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>The first modification was a new carb-jet
that OS provided FOC to cure a mid-range gurgling problem. Back
then, the motor was a novelty and not taken seriously, even though it
pulled my old Hydeout vertically out-a-sight. Things went quiet for a
while and around the year 2000 there was an upsurge of interest. The EFI
caught a lot of attention and then the experimenters started working on their
2-cycles of all types. The second modification was to fit stainless steel
bearings :-)</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>The price of the OS 1.40 EFI made
us look at the RX again. Dave Shadel came out with a piston and liner. Fuel
was modified to meet the spec's that OS had always listed. Coolpower was
always around 15/17-18 and often proved to be the best fuel for the average
pattern OS 2-c pundit. The OS 1.40 RX had a different shaft and carb by then.
The new carb had a bigger throat and the shaft had a narrower mouth. Never got
to try an old shaft with a new model carb. Did cut a 1.40 two plug head that
was never tested. Found out that one OS "F" did the job with less
plug-fuss.</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>The Shadel liner is not a must but does
give more power. I like it because it is an aftermarket add-on that anyone
could fit. Another aftermarket is the OS mixture carb. I first heard of this
from Jeff Carrish. I then got to fly one on Dixie-Chicks-Earl's Temptation.
The Webra MC testing got me interested and then the flight-experience
convinced me that this carb (Approx. $79) makes a big difference. You have
five points on the carb and seven on a JR 10X. You can adjust the carb to
perfectly match the behavior of almost any pipe. With the OS Hatori and this
carb on a 1.40RX it was just like flying the 1.40 EFI. ( This motor BTW still
had the std liner etc.)</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>I was so impressed with the tunability of
this carb that I am fitting one to my 1.60 as soon as it arrives in the mail -
checking for it every day...!!</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>As much as I like to only do easy after
market mods, I did break down with the OS 1,60. The 1.40RX pump was so good
that I grafted one to my motor and ran it last season. The 1.60 Carb worked
just fine and I am told that the 1.40 RX carb works even better, at
least in Norway or Sweden? (They all have 15 mm openings in the
crankcase). An OS 1.60 FX w/pump and an OS mix carb should be pure fun
to play with and of course, fly!</FONT></SPAN></P>
<P><SPAN lang=en-us><FONT face=Arial>I still hope that OS will come out with a
rear exhaust 1.60, (or more), w/pump.</FONT></SPAN> </P>
<P><SPAN lang=en-us><FONT face=Arial>Is winter over yet?</FONT></SPAN> </P>
<P><SPAN lang=en-us><FONT face=Arial>Regards,<BR><BR>Eric.</FONT></SPAN>
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