I ordered a new d606 rear tire last night and to qualify for free shipping. I had to buy something else. ) I bought an Iridium spark plug. What I want to know is if it is going to make any lick of difference to a completely stock 06 250s? or should I wait to put it in until I rejet and put a pipe on it? which wont be until this winter

 

I put one on my 351 and didn't notice anything.

I'm sure it helps the burn.

 

got one...

Placebo...

Just my humble opinion...

 

I found my 09 starts easier, doesn't need the choke much anymore. Other than that, I can't tell a difference.

 

I got one, didn't notice any difference. I also changed gearing at the same time, so maybe it did do something.