Spark plug Check

[david lee]

Spark plugs can tell you a lot . Fuel mixture,the correct timing, also if you have bad rings or valves . If you use never seize you will muck up some of the readings . Also NEVER take a plug out of a hot motor . You will risk of pulling to threads out . Remember aluminum is soft when it is hot .

How does never seize muck up the readings?

never knew that.how would you check main jet size. ive read that you supose to ride down the highway at a certain speed,hit the kill switch, pull the plugs and check color ?

[Ironheadmike]

If you cover the threads you won't beable to read them . The color of the first threads and how high the color goes up the plug will indicate how hot the bike is running . A gentleman by the name of Kevin Baxter has a very informative video on reading plugs .

[Ironheadmike]

I check the main by timing how long it takes to go from point A to point B . The best time is the right jet . Your main is on from 3/4 to wot . Like I said if you pull the plugs when hot you will damage the threads eventually .

[Scotty]

You boys are all living in the past. You can't even read plugs correctly with the way fuel is now.
Come into the 21st century with the rest of us and run a O2 sensor and really get to know what your bike is doing.
Talk about doing things half assed.................

[kd]

   I was waiting for someone to bring it up.  You sure can't read a plug like you used to with todays unleaded corn fed fuel.  That's a fact.  Use the tools available and you'll know what you have to a decimal point and not be guessing.  Chopping the throttle, pulling in the clutch, rolling to the shoulder, engine temp, barometric pressure and humidity are demons that can't hide from an AFR gauge reading.  Besides, even if you could get a decent reading with modern fuel like "the old days", it takes a while for a plug to imprint properly and then you need to know what load and rpm range etc., etc., that you were in. 

[Ironheadmike]

You boys are all living in the past. You can't even read plugs correctly with the way fuel is now.
Come into the 21st century with the rest of us and run a O2 sensor and really get to know what your bike is doing.
Talk about doing things half assed.................

That's all good for rich/lean but can you little o2 reader tell if your timing is off or bad rings or valves ? A plug can. Even with today's gas you can still read a plug if you know what you are doing and know what to look for .

[Scotty]

You boys are all living in the past. You can't even read plugs correctly with the way fuel is now.
Come into the 21st century with the rest of us and run a O2 sensor and really get to know what your bike is doing.
Talk about doing things half assed.................

That's all good for rich/lean but can you little o2 reader tell if your timing is off or bad rings or valves ? A plug can. Even with today's gas you can still read a plug if you know what you are doing and know what to look for .

No it only measure AFR which is one big part of the equation.
Experience will get a person the rest of the way but anyone claiming they can read the AFR on a plug with todays unleaded fuel is living in a fantasy world.

[JW113]

This thread is digressing into two different topics.

Yes, one can get some diagnostic information from taking a look at the plugs. No question about it, I do it all the time. You can get information about the state of the engine. But, that is only part of it, you need to do a lot more than read plugs. And to tune the carb/EFI, forget about it. It might get you "somewhere in the ball park", but very unlikely ever a home run. I'm tuning my Shovelhead right now. The plugs look great. However, the AFR was WAY off.

The other topic is tuning the fuel delivery. All it took was once for me to try it myself with an AFR gauge, and there is no going back. The only way that I believe you could tune a carb/EFI as (maybe) accurately as an AFR gauge is either on a dyno and tune for max HP at WFO, or on a drag strip for best ET. And that is ONLY for WFO. What the AFR is at idle and cruise and part throttle, you will have no idea.

Resistance is futile. Why fight it?

-JW

[Ironheadmike]

I wonder how people got by before electronics told them what to do . Just like cell phones . IMHO they made people dumber and lazier. All these electronics telling people what to do, what would they do without them .

[Hossamania]

They would rebuild their motors every 20 or 30 thousand miles due to improper tuning.

[Scotty]

I wonder how people got by before electronics told them what to do . Just like cell phones . IMHO they made people dumber and lazier. All these electronics telling people what to do, what would they do without them .

Keep living in the past and trying to insult people by calling them dumber and lazier.
Sounds a lot like you are jealous of people who can & have embraced technology.
Still room for everything we learned from when we ran leaded fuel and had points instead of electronics but the world has changed and some of us went along for the ride and were not afraid of change.

[JW113]

I wonder how people got by before electronics told them what to do . Just like cell phones . IMHO they made people dumber and lazier. All these electronics telling people what to do, what would they do without them .

Au contraire, Mr. Ironhead Mike. I disagree completely. Let's take your example, cell phones, which is really a "smart phone". In order to use one, you need to know a heck of a lot more to use one than how to use an old rotary dial or push button phone from 40 years ago, when we were young. You need to educate yourself, else all the power of that smart phone is useless. The same is true of modern tuning equipment, like a dynamometer. You think any moron can just strap his bike to a dyno, and use it? No. The same is true with an AFR meter. You need to learn how to use it, and in the process, you gain knowledge. In fact, the first thing you learn is that what ever you thought you know about tuning without one, throw it in the trash. No comparison.

So... let me ask this. You want to take the Pepsi challenge, and try to out-tune an AFR? The irony of this question is, you would never know how well you did without an AFR to check your results.

Dude... this argument is not worth having. Like claiming you can time a motor better "by ear" than with a timing light.

No disrespect. Just trying to share the love. We live in 2022, not 1965. And we're all smarter now than then.
 

-JW

p.s. by the way, I am very concerned at how our society had turned into a world of "palm zombies", of which I proudly refuse to participate in.

[Ironheadmike]

I got 60000, 110000, and 55000, on my bikes . All stage 3 I just swap out lifters every 25-30000 miles. I also get 48-50 mpg . So that shoots your 20000 build theory out of the water . I'm not trying to insult anybody, I forget people are sensitive these days. Just stating 40 years experience . Besides the 20000 rebuild mark was due to poor oil circulation in the shovels and pans