Iridium spark plugs in Curvy?

Just a quick question for you lovely people, and it obviously concerns spark plugs.

I've currently got a pair of CR9E spark plugs in my 2000 SV650S, not by choice but because they were sent to me by accident instead of a pair of CR8E plugs. Now I know that it shouldn't really make any difference but to me it seems like the bike is running rougher when cold than it used to and so I was looking to change them.

So, I have a pair of CR8EIX plugs lying around somewhere in my garage and so just wanted to ask if anybody on here had run their SV with iridium spark plugs and whether or not they work fine, and if I will see any improvement over running with standard plugs.

Thanks.

I've got NGK iridium plugs in my curvy and it runs nicely, slightly smoother than non iridium but it may just be a placebo.

NGK plugs and there numbers are quite easy to understand and I find them to be the best quality. The CR9E plugs are a cooler running plug than the CR8E...meaning that it can work at higher temps due to higher c/r or slightly leaner fueling or constant high revs....from my 2stroke days, I found that NGK "V" type plugs worked and lasted very well..these were the racing plugs of the day, Iridium seems to be todays race plug, iridium being very durable. But if you`re not using high revs all the time, and a sv650 on the road really dosen`t need to be rev`d hard to make progress, a CR8E or even a CR7E plug may be more suitable, as they will self clean better at low revs and during warming up..just listen for any detonation if your using a hotter plug like a 7 tho I don`t think it will be a problem.

[Sid Squid]

Stick with the standard grade whatever type you use.
The SV does not require the theoretical advantage that iridium plugs might give. Their advantage is in not fouling so readily and theoretically staying gapped correctly for longer.
Except for the possibility that they might allow slightly easier starting in marginal conditions, i.e. cold, wet, low battery etc etc, there's no benefit in them in an SV, and if your bike is maintained correctly then they won't make any difference then anyway.

[Spanner Man]

Good morning all.


As Sid says. Stick with the standard heat rating. NGK plugs have quite a wide heat range. I've never seen a road going SV in good mechanical order that would have gained an advantage using a cooler, or hotter plug.
There's usually a minimal improvement, normally to low speed running, when switching to Iridium plugs. Whether it's worth the extra cost is up to you.

Don't fall into the trap of thinking that Iridium plugs will last longer. They don't.


Cheers.

I thought iridium plugs should last longer, as it`s a very durable metal that doesn`t erode like standard plugs..tho the extra cost is high...I`ve got them in my mx5 and not seen any difference in the slightest. I would think its better to check and change plugs more regularly than fit some and leave em in for years...only to find they wont come out at service time...I`m just the same with these long life oils...better to change it more often, but still use the best you can get.

[NTECUK]

Put the right standard plugs in it.
Your get just as much power improvement if instead og iridium plugs you wear your pants on the outside of your leathers....

Originally Posted by Sid Squid

Except for the possibility that they might allow slightly easier starting in marginal conditions, i.e. cold, wet, low battery etc etc, there's no benefit in them in an SV, and if your bike is maintained correctly then they won't make any difference then anyway.

Iridium plugs do seem to have made a significant difference to me. I was suffering from fouling when starting in cold damp conditions and they appear to have made a real difference in that regard. I also thought that I got better engine response in the 7k-9k rev range, but a new set of standard plugs might have also given the same impression.
The difference in ease & reliability of starting in the winter makes them easily worth the money for me, but perhaps there's something else that I'm not maintaining correctly to make this the case. Last time I had it in the dealers they did say it seemed over-rich at tickover, but didn't have any remedial suggestions.