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The plugs of racing karts are susceptible to carbon
fouling, but how does Iridium Power do in this case?
We frequently hear that Iridium Power is resistant to carbon fouling compared to
plugs from other companies. However, there is no way that they are a 100%
solution, and it's good to know these techniques to prevent carbon fouling.
[1] When rolling in the race, close the carburetor's low
needle or pinch the fuel pipe with your hand to prevent
excess fuel from entering the engine.
[2] By pumping the accelerator during rolling, a rich fuel air
mixture goes into the engine, making it easier for
carbon fouling to occur. Operate the accelerator gently.
[3] If carbon fouling happens while running with the throttle fully open,
this could mean that the heat range is too low or that the fuel mix
is to rich. Consult with a kart shop to find the optimum setting.
How is the compatibility with plug cords such as Nology?
There are no particular issues with compatibility. In fact, there are some
cord manufactures who sell products "especially for iridium plugs."
When changing plugs, is there any need to
change the settings?
For normal vehicles, there is no need to change the settings.
It is advisable to reset vehicles with modified exhaust
systems, though in most cases adjusting the air screw is
sufficient. (Except for racing carburetors such as FCRs)
Is there a way to tell them apart when replacing them?
This can be done by confirming the level of wear (the gap width) on the ground electrode.
DENSO's Iridium electrodes are different from conventional products in that their center electrodes
hardly wear, and because of this it is better to check for wear on the ground electrode .
T h e t e r m i n a l o n t h e e n d o f t h e p l u g i s
frequently unnecessary on motorcycle, so
why is this included with all types?
Iridium Power comes standard with a plug terminal (not including
combined types). This is because some of the other companies'
plug cords require a terminal, and at DENSO we decide our
product specifications keeping in mind every customer.
Are plugs such as VUH27D and VK24PRZ11 for Honda
vehicles available as Iridium Tough plugs? Will they last
100,000km? Also, can Iridium Power be substituted here?
Plugs for 2-wheel vehicles with a "V" in the part number have a platinum tip
welded to the ground electrode, the same as in 4-wheel vehicles. They have
more durability than Iridium Power, but do last 100,000km. Thus we do not
offer them as Iridium Tough products. You can choose the Iridium Power
plug for those vehicle types with a compatible Iridium Power plug shown in
the Model Chart; however, please understand that it will be not as durable.
I'm using Iridium Power. If there is carbon
fouling, can I use a brass brush to clean the
plugs?
Because Iridium Power's center electrode has a fine 0.4mm diameter,
there is a chance that this electrode could be bent by a brass brush. If
you having the plug cleaned, a sandblaster-type plug cleaner found in
maintenance shops is preferable. If this is the case, keep the air
pressure low and clean the plug for as short a time period as possible.
Also, one trick would be to dissolve the carbon with an engine
conditioner or a similar chemical agent. (Parts cleaners will not
dissolve carbon). After applying it, take a nylon brush (don't use a
wire brush) and scrub it off, wash it well, and dry it off. Repeat this
procedure three or four times to remove any carbon. DENSO has
confirmed that this does not return the performance of the plugs to
100%, so please use this as a stopgap measure.
The vehicle seems to be running worse now that I've installed them?
In most cases there is a problem with the vehicle. Scooters are
often run for long periods of time without maintenance, and it is
common to see them with richer fuel-air mixtures from dirty air
cleaners. Our investigations have found that these vehicles tend
to be susceptible to carbon fouling, and when replacing plugs
also remember to inspect and clean the air cleaner. The
effectiveness of the change should become even more apparent.
Also for rough idling and problems starting, sometimes reducing
the plug gap by 0.1 to 0.2mm will solve the problem.
