How often should a set of plugs be changed?
Marsh

 

Think the book says 20K, I changed @ 16K and could tell the difference in the way it ran.

 

I do it every time I change the oil. That's not necessary, I know, but it's only a couple bux so I just do it every time.

 

changed at 5k, 15k, and now at 30k I'll do them this spring.

 

I change 'em every 5000 miles, whether they need it or not. And at the start of riding season. They're cheap enough and good for peace of mind.

 

Exact, same proceedure here!

 

If you have a modern HD four stroke fuel injected engine and it has not been "tuned" just follow the service manual. If you have it all jacked up like most of us with custom tunes, pipes and aftermarket air filters no telling, just gotta look at the plugs.

 

I change my plugs every spring no matter how many miles are on them. I just figure the cost is not prohibitive and it doesn't take but a minute or two.

 

Change mine every spring after the thaw. Bike sits for about 4 month out of the year.

 

Glad this post come up. I haven't changed my in about 3 yrs now. Guess I'll change them when ever I get around to buying some.