Gapping spark plugs

Less important than it used to be, for varying reasons. Platinum/iridium plugs are harder to gap without damaging the fancy electrode, and so they often come pre-gapped. Also, modern motors tend to run similar compression ratios and air/fuel mixtures, and so the variation in gap is small - even if the gap is incorrect, you may not notice under most conditions.

That said, it depends on the plugs and the bike. If you bought cheap plugs for an old bike, you might want to spring the additional handful of dollars for a gapping tool. Most of them are **** unfortunately
 
They probably work fine right out of the box, but I'm old so I check them all. I haven't had to reset one in 15yrs and I change dozens.
 
I just replaced mine and out of four, one needed to be adjusted. The tool is around $5 and can be bought at Canadian tire. Peace of mind.

Don't leave the tool in when closing the gap or you'll damage the electrode and if opening the gap be carful not to pry on the electrode.
 
Another vote for likely ok. I changed plugs on my bike last weekend (NGK CR7E) and when I used my feeler gauge the gapping was already correct. Same experience on 5 previous bikes, only one I recall gapping not being correct for out of the box was my 1992 nighthawk.
 
If you haven't purchased the plugs yet. Try to find the OEM plug model part number. Most likely it will be within the gap range as noted in the owners manual right out of the box.

What I mean buy OEM part number is that sometimes the parts place will give you an equivalent plug type. But in my recent experience the OEM plug was dead on for gap while the first set equivalent was off. The gap spacing was shorter than recommended. I didn't want to risk damaging the plug by adjusting the gap. (Iridium). So I went to exchange for OEM.
 
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what plug are we talking about here ? NGK? BOSCH?

The reason to check gap / adjust is also if the box was dropped, then it would be out of spec. so its a good idea to check.
 
If you go back 50 or 60 years, checking the gap was essential.
Just a few millimeters out could make the engine run rough.
Nowadays, it isn't that important.
In the dinosaur days there was a big difference in the gap between a Harley and a Honda.
Now, they are all pretty much the same.
I still have my original gapping tool from the old days and I still check (force of habit)
But I can't recall the last time one was wrong coming out of the box.
 
Another vote for always checking and being able to count on one hand the number of plugs requiring adjustment in my lifetime.
 
The bike is only about 10 years old it's a Yamaha v-star so it's not that old

I don't remember the brand he bought


thanks everyone I did not realize the tool was Cheap it doesn't hurt to have one anyway.
 
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