Douwe EgbertsEgberts CAFITESSE 300, Руководство по обслуживанию

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How does the engine respond to changed settings?
We sometimes hear that "Iridium Power is too sensitive to
setting changes." However, the flip side to sensitivity is
that "the response to setting chages is fast and easier,"
and during races, we hear that it makes setting changes
easier. If Iridium Power is used, it should become possible
to draw out more performance from your vehicle.
What is the difference in the life of an iridium plug used under
2-cycle conditions and one used under 4-cycle conditions?
In 4-cycle engines, a spark is produced for every 2 revolutions of the
crankshaft, resulting in explosion and combustion in the engine.
In 2-cycle engines, a spark is produced for each revolution of the crankshaft,
resulting in explosion and engine combustion in the engine.
This simple comparison may lead you to conclude that 2-cycle engines simply
have twice the wear; however wear is made up of not only wear from sparking,
but also wear from high temperatures (oxidation).
Thus, the amount of wear depends on the driving conditions of the vehicle,
how the rotations of the engine are applied (that is, how the shift is used), and
whether the resulting combustion temperature is high or low.
2-cycle engines have a higher level of electrode wear. This electrode wear is
estimated at approximately 1.5 to 2 times that of 4-cycle engines, and plug life
is also shorter with 2-cycle engines. Iridium has a high melting point; however,
it will undergo wear from sparking and wear from high temperatures
(oxidation). To our knowledge, 2-cycle engines are only found in 2-wheel
vehicles, our recommended value in this catalog for lifetime is 3000 to
5000km. (This value is based on a variety of conditions, and, racing use may
require even more frequent replacement.) From the above, it is recommended
that plugs for 2-cycle engines be replaced about every 3000km. However, the
condition of wear depends on operating conditions and the typical engine
rpms, so it is also possible to take out the plugs occasionally to confirm the
amount of electrode wear and judge when the best time is to replace the plug.
I ride a BMW R100RS ('92) motorcycle. I bought
Iridium plugs (IW20, as specified in the charts) and
installed them, but whenever I stop at the stop light,
my engine stalls. Is this a defect with the plug? Or
does this mean that my motorcycle is unsuited to
Iridium Power? How can I get them to work?
Because Iridium Power plugs have an ultra-thin center electrode, they
will spark even at low voltages (i.e. they have low voltage
requirements), and we are proud to say they have excellent
compatibility with older cars with weaker electrical systems.
However, in general, some older vehicles (not only the BMW motorcycle
in this question) appear to have a degraded ignition systems from age,
resulting in sufficient voltage not being available from the coil.
For improved ignitability, the low heat range Iridium Power plugs have a
spark gap of 1.1mm, and in vehicles with a significantly weakened
electrical system, this may result in symptoms such as "rough idling"
and "lack of power." Adjusting the spark to between 0.8 and 1.0mm
should solve this problem.
However, because the center electrode is extremely thin, please have
this adjustment done by a professional mechanic.
I installed Iridium Power plugs on to my 2-wheel
vehicle. Sometimes when I start it, there is a
loud, explosive "pop." With regular plugs this
did not happen. Why is the reason for this?
A loud explosive "pop" pop sound can have the following two causes:
(1) An afterfiring muffler
(2) Backfiring due to blowback from the carburetor
If it is the same vehicle and these symptoms were not there before
changing to the new plugs, the reason for this is (1) afterfiring. The
causes of afterfiring are:
(1) An abnormally elevated intake pressure, the combustion becomes
unsteady (during engine brake)
(2) A problem with an ignition device (improper ignition timing, misfiring)
(3) The fuel-air mixture is too rich (problem with the carburetor, too
much choke)
(4) The valve timing is off
If the problem is during starting, (2), (3), or (4) are thought to be the
reason. A specific example for (2) is "ignition timing that is off" and
specific examples for (3) include "a dirty air cleaner" and "pulling the
choke too much."
We often hear that Iridium plugs improve ignitability so much that
people "don't have to pull the choke to start the engine." If you are
pulling the choke to full, try pulling it to the "halfwayﾓ point and see if
this solves the problem.
What kind of vehicles are surface gap plugs used for?
These are plugs developed for racing, and there are many people who use these plugs in
the All-Japan Road Race Championship JSB1000 class and in drag racing. Because the
ground electrode is gone, there are the following advantages and disadvantages.
■ Advantages
[1] When the engine is tuned so that the compression ratio is
increased, these can avoid interference with the piston.
[2] Because there are no excess projections into the combustion
chamber, the combustion efficiency at high revolutions is improved.
[3] Difficulties due to the ground electrode can be prevented.
■ Disadvantages
[1] The ignitability becomes worse, and thus feeling and
response at low and mid-revolutions deteriorates.
(2) The engine characteristics become peaky; because of this, in
the popular ST600 class, where conditions are severe, there
are many people who use plugs with ground electrodes.
Is it true that installation on Ducati water-
cooled 4-valve engines is not possible?
Since the 996R, the interior of the Testastretta (narrow head)
engine's plug holes have been very narrowly machined, and with
regular plug wrenches, the socket OD hits the wall and thus the
plugs cannot be fully tightened. (Not possible with a 21.5mm OD)
In this case, a thin-wall plug wrench is required. [We recommend
the "NB3-16SP (nepros)" or the "B3A-16SP" by KTC.]