Could someone please explain me the differences between these?

NGK CR10ER VS CR10E

and

NGK CR10E VS CR9E

Are they just temp. controlled?
What does the addition "R" stand for...? I cannot seem to find any dealers that stocks the CR10ER.

The plugs that are in that motor stock plugs for a R6 i think, any yamaha dealer should have them.

NGK provides meaning behind the codes here: http://www.ngksparkplugs.com/tech_suppo ... p?mode=nml

According to above there shouldn't be an 'R' at the end of CR10E? In any case, the letter after the 'E' refers to firing electrode type.

When i replaced the plugs in that engine i ordered the codes that were on the plug and when they turned up they only had a single electrode, the old ones were twin electrode. It turns out theres 2 types of the plug, single and a twin electrode. I ended up getting them from RLR then later discovered my local yamaha dealer stocked them.

Drunkn Munky wrote:The plugs that are in that motor stock plugs for a R6 i think, any yamaha dealer should have them.

The 10s are not stock plugs for any UK spec R6, they're too cold. CR9E is the stock plug

R is a resistor plug (and more common)

The resistor is built into the spark plug.

Some bikes have the resistor built into the plug lead and thus do not require the spark plugs to have a high resistance.

Sometimes you can use the resistor plugs in place of the non -resistor plugs but your not supposed to use it the other way around (i.e, non resistor plugs in bikes that require resistor plugs as it can generate too much interference)

With modern ECU's the difference in resistance could affect the spark more, you'd have to contact the dealer or just try it.

The NC24 is the same.. it specifies non resistance plugs (C8EH9) but many people fit CR8EH9 as they are cheaper without ill effect, but this has old coil packs and not modern ecu monitored stick coils.

The plugs your after will probably be special order, either the bike mfg dealers or try ebay.