Spark Plug

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I just bought 2 spark plugs, NGK CMR7H. Just one thing I'm semi-worried about... the spec says the gap should be 0.7mm, but it seems to be larger than that, I would say about 1.25mm. Both of them have the same exact gap. So the question is: do I need to find a tool to set the gap? Shouldn't they be properly set from the factory?
 
they don't always come gaped correctly from factory. best to check and gap them yourself. you can pickup the tool at any auto parts store for a buck or so. they make one that looks kind of like a coin with a hole in it so you can keep it on your key ring.
 
At a closer look, it looks like maybe they are set... I noticed I received "CMR7H-10", which has a different gap in spec, 1.0mm (probably that's where the "-10" in the name comes from). Anyone know if the 1mm gap is ok for the Redcat engines? I saw mentions on the web about having to adjust the gap according to the specification from the engine's manufacturer.
 
Ice_2k said:
Yes, why? :)
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The reason why I ask is any body with a street bike .atleast anyone that I know kind of knows spark plugs atleast the most basic like heat range and what a gapping tool is.thats it....
 
plugs

Ngk- denso- plugs from japan, china, the higher the number, the COLDER the plug. American plugs, even if they are made overseas-- Champion for example-- The higher the number, the HOTTER the plug, this includes Autolite also. Iridium. This element is not natural to earth. Iridium is mined out of the earth in areas where metorites hit the earth long ago. It is used to put a very thin coating on the fine wire center electrode on spark plugs. This coating will not increase the voltage across the plug gap. It does reduce the strain on the engines coil. The idea with these IR plugs is this-- They last much longer in newer automobile engines, modern engines are sometimes a pain in the ass to even change the plugs. When i say they last longer- The IR coated fine wire center electrode lasts at least 3 times longer before the heat & spark erodes the center electrode away. In a 2 cycle engine, at least the little hobby motors we use, I see no advantage at all in running these types of plugs. just my opinion.
 
Ice_2k said:
Thanks, I'll search for it.
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It's 0.028 in imperial

The last one I bought was set at 0.025 from the factory and yes that 0.003 seems to make a difference even though you wouldn't expect it to
 
What kind of difference might I expect? I mean, after installing it and starting the engine (provided it starts), what are the signs of an incorrectly adjusted plug?
 
Ice_2k said:
What kind of difference might I expect? I mean, after installing it and starting the engine (provided it starts), what are the signs of an incorrectly adjusted plug?
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Nothing big

It just seemed to rev better at 0.028
 
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