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<DIV>I made a dual plug head for the OS 1.40 and for the 1.60. I also
ran two Mintor 1.60's.</DIV>
<DIV> </DIV>
<DIV>I know before I type what follows I may well draw some fire, but after
two years of using twin-plug-heads on different motors<STRONG> <EM>I am
personally convinced that they are a total waste of money and
time.</EM></STRONG></DIV>
<DIV><STRONG></STRONG> </DIV>
<DIV>If you are using a twin plug head to fix a "problem" there is probably a
better fix!. </DIV>
<DIV> </DIV>
<DIV>I went through over 60 plugs of all types. I still have a can-full of
them in my van. Constantly, I saw the lower or rear plug fail, It always ran
better with the center plug working but you had to reset the carb. One argument
is the engine keeps going if you lose a plug. The reality that I experienced is
that there was a big loss of power and often overheating when one plug went
out. Twin plugs change the ignition timing of the engine. Two plugs
of the same type, A-3 "F"etc. or mixing rated plugs all interfere with the
timing and design of the motors combustion.</DIV>
<DIV> </DIV>
<DIV>Of course there are a whole bunch of folks that are happy with two
plugs and are convinced that they are the way to go. I say enjoy and I'm
glad for you, really!</DIV>
<DIV> </DIV>
<DIV>My 1.40's, and I say mine whether I still own them or not, run like watches
on one plug. My OS 1.60's run great on one plug. The FI or Mix-carb versions, it
makes no difference, if you set the carb correctly and use the right volume
of pipe, they run great. I literally gave up on my 1.60
Mintors, especially after I was informed by the supplier that I did
not know what I was doing with 2-cycles! I acknowledge they could
well have been right, but there was no available information to fill the vacuum
of why and what was the reason that they did not
work. (Ironically enough the factory agreed basically with my findings and
changed the guts of the product) The upgraded piston and liner ran better but
they still kept killing plugs at a much higher rate than a single plug set-up.
</DIV>
<DIV> </DIV>
<DIV>But I digress. The twin plug does give a lower idle and does help through
transition on a tuned pipe. However if your engine will not run at an
acceptable idle on one plug something else is amiss. For example. wrong plug,
wrong fuel, idle mixture is off, bad bearings, tight ring/liner etc. Similarly
on transition problems. I have noticed that quite a few so called tuned pipes do
not have much of a tapered cone to the main body of the pipe. Mix carbs and
double plugs might get you through these issues, It's your choice.</DIV>
<DIV> </DIV>
<DIV>Regards,</DIV>
<DIV> </DIV>
<DIV>Eric.</DIV></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=rodney19821982@yahoo.com
href="mailto:rodney19821982@yahoo.com">Rodney Tanner</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> Wednesday, April 20, 2005 2:48
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [SPAM] Re: RE: OS mixture
question</DIV>
<DIV><BR></DIV>
<DIV>Hi Ron,</DIV>
<DIV> </DIV>
<DIV>Eric H, or Dean P would probably be the best people
to answer that.</DIV>
<DIV> </DIV>
<DIV>I forget how many variables back I changed to the 3M heads. My basic
take would be that they give a smoother mid range on an ESD pipe,
are less sensitive to pipe setting, lower the compression - so run cooler,
without affecting the top end performance. </DIV>
<DIV> </DIV>
<DIV>Rodney</DIV>
<DIV> </DIV>
<DIV><BR><B><I>Ron Van Putte <vanputte@cox.net></I></B> wrote:</DIV>
<BLOCKQUOTE class=replbq
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid"><BR>On
Apr 20, 2005, at 8:11 AM, Cameron Smith wrote:<BR><BR>> Are you supposed
to change em? Seriously I change both plugs about <BR>> every 3 to 5
cases of fuel. Sometimes I just rotate the center plug to <BR>> the back
position then replace the center plug. I replace ANYtime the <BR>> engine
deadsticks or acts to much out of character. Most times they <BR>> are
still good.<BR>> A buddy checked my idle the other day on my NEW
Single plug (STOCK) <BR>> head & it also Idles at 1K. Gotta luv
it!<BR><BR>I've got to ask this: Is there any real difference in the way an
OS <BR>1.40RX runs with the Mintor 1.40 head 'extra' plug in the 'front' or
<BR>'rear' position? I know that Lance says to run it with the 'extra'
<BR>plug in the 'rear' position, but I theorized that there would be better
<BR>fuel ignition if the 'extra' plug was in the 'front' position, as far
<BR>away from the exhaust as possible. I've been running mine that way and
<BR>the engine runs fine.<BR><BR>Ron Van Putte<BR>>
<BR>>
<BR>>
<BR>> -----Original Message-----<BR>> From:
discussion-request@nsrca.org <BR>> [mailto:discussion-request@nsrca.org]
On Behalf Of <BR>> Jim_Woodward@beaerospace.com<BR>> Sent: Wednesday,
April 20, 2005 8:57 AM<BR>> To: discussion@nsrca.org<BR>> Cc:
discussion@nsrca.org; discussion-request@nsrca.org<BR>> Subject: Re:
[SPAM] Re: RE: OS mixture question<BR>> <BR>><BR>><BR>> Hi
Rodney,<BR>><BR>> Why are you changing plugs every 30 flights?
That get pretty <BR>> expensive in the long run. Is the
engine running lean? I've seen a <BR>> few other using the 3M head
and OSF plugs, and not having to change so <BR>> often.<BR>><BR>>
Cameron, how often are you changing plugs?<BR>><BR>> Thanks,<BR>>
Jim W.<BR></BLOCKQUOTE>
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