spark plug type

[franco6]

spark plugs bought new ones ,asked for cold plugs ,was given ngk dpr8ea .took the ones on the bike off they were  ngk dpr 7ea . are those colder? there is also a R on the plug is that racing? has anyone tryed the bosch xr4cs? thanks for the help.
Fred

[roboto65]

The 8 is colder than the 7 and the R stands for Resistor LOL my first post!!!

[franco6]

ROBOTO65 thanks for the info. i gota hold of the plug co that what they told me. i got some nines what do you think? its so hot here ,the f6 is running hot too. tomorrow i ll do a carb sync . the 7 plugs looked good so don t think i have too much trouble there .going out for atest drive now 7:49 pm, 98F its not cool! it is my wife s birthday so we ll go for abite so she can appreciate the new plugs i got her for present.

[daytona]

Japan plugs and yank plugs are diff on heat # ratings, The longer the insulator (white around electrode) the hotter the plug. less of it allows the heat to dissipate to the head faster.

[franco6]

Japan plugs and yank plugs are diff on heat # ratings, The longer the insulator (white around electrode) the hotter the plug. less of it allows the heat to dissipate to the head faster.

thanks DAYTONA .tried 9s the f6 kept dieing ,mileage fell to 24 mpg , so going back to the old 7s until i can try the 8s. daytona beach was my favorite place to hang out when groing up in orlando pre wdw. fla was a nice place then!