Spark Plug Heat range

[fjman]

The stock plug is ngk dpr8ea-9. I'm looking into running on a hotter plug. What number would you guys recommend? 

[andyb]

http://www.ngk.com/sparkplug411_manufacturer.asp?manufacturerID=1

Wouldn't change more than one heat range at a time.  Why are you needing this?  Are they fouling or something?

[fjman]

I usually ride on a stop and go basis.  I only go for short distances.

[candieandy]

Running 1 step hotter will be fine for idle and low speed crusing, but will be an issue in the 6-9K rpm range with the engine under load. too much heat will be retained in the center electrode and could cause a preignition issue.  Use a DPR8EIX-9 #2202, i use this plug and commute is 2 miles one way. The Iridium IX holds up much better to fouling conditions, if thats an issue you are experiencing, but if the bike is too rich, you will need to adjust the carbs.

[racerrad8]

I usually ride on a stop and go basis.  I only go for short distances.

You should not have any issue with fouling due to the wasted spark on each cycle. This wasted spark cleans the plug, unless there are other issues causing the plug to become heavily deposited.

I only use the NGK DPR8EIX-9 in all of my applications from the bike to the car. The small tip heats faster and stays cleaner.

Randy - RPM

[yamaha fj rider]

The DPR7EA9 is one step hotter. The 8 should be fine. Hope this helps.

Kurt