Suzuki V-Strom (VStrom) Owners Club DL250, DL650, DL1000 & DL1050

V-Strom specific discussion => V-Strom specific discussion => Topic started by: Theflyingscot on March 15, 2015, 13:58:43

Title: Spark Plugs
Post by: Theflyingscot on March 15, 2015, 13:58:43
Just finished a quick service on the Vee.
Now this may be a daft question but I purchased CR8EIX plugs but the ones I have removed are CR9EX, after looking through the owners manual it states to fit the CR9's if the CR8's overheat.
How can you tell if your spark plugs are overheating?
Title: Re: Spark Plugs
Post by: greywolf on March 15, 2015, 14:39:48
You are running a liquid cooled bike on the street. Stick to the 8s. Whoever put the 9s in was confounded by theory.

A plug that runs hot will exhibit faster electrode erosion.
Title: Re: Spark Plugs
Post by: Theflyingscot on March 15, 2015, 15:24:50
Thanks for that, would the 9s contribute to poor running?
Title: Re: Spark Plugs
Post by: greywolf on March 15, 2015, 15:57:46
Poor running could occur if the electrodes were worn.
Title: Re: Spark Plugs
Post by: Theflyingscot on March 15, 2015, 16:12:52
They looked in okay condition, a little sooty though.
Title: Re: Spark Plugs
Post by: hookie on March 15, 2015, 16:16:15
The higher the number, the cooler the plug will run I.e. it is less likely to over heat if the bike is driven very hard. Using a cooler plug (higher number e.g. 9 rather than 8) than the engine needs is more likely to foul as it doesn't run hot enough to be within it's design limits. I can't really see any situation where 9 grade plugs would need to be used a Vee except perhaps speed testing at Daytona! Even the TL1000 sport bikes only used 8 grade plugs.

If they a bit sooty, this could indicate that they're not getting hot enough. Hence the 8 grade plugs would be a better choice.
Title: Re: Spark Plugs
Post by: greywolf on March 15, 2015, 17:27:25
Yeah, I got it backwards. 9s are cooler and will tend to develop deposits that could affect running.
Title: Re: Spark Plugs
Post by: Theflyingscot on March 15, 2015, 17:29:39
That would explain it then, let's see how the proper plugs do.
Title: Re: Spark Plugs
Post by: tallpaul on March 15, 2015, 20:10:11
I fitted CR8EIX plugs to my brothers vee. It runs perfectly well on them.
Title: Re: Spark Plugs
Post by: hookie on March 15, 2015, 20:28:38
The CR8EIX Iridiums will be fine and should last 30,000+ miles. I've had a set in mine for over 20k and still going fine.