1964 FLH Spark Plugs Fouling

[T. Cotten]

The service manual states to adjust the low speed needle out five full turns from lightly seated and that the motor will start but it will be rich. My recent experience doing this on a newly rebuilt 48EL is that five turns is WAY too rich and my plugs looked just like the ones in your photo. I discovered that about two turns instead of five did the trick. Of course this is just a starting point. If that fails then any of these other suggestions should be explored. Just my 2 cents . . .

I always figured, Gitguy,

They spec'd such a fat starting place because nobody knew how to find a vacuum leak.

My assemblies went out at 3.5 turns, expecting to be trimmed in even further, and received no pertinent complaints for decades.

...Cotten

[BigLakeBob]

Even with a proper float at proper level, Otis,..

It will overflow while sitting if the petcock leaks.

No floatvalve is absolute.

....Cotten

Are you saying if I stop my bike and don't close the petcock my carb will overflow? I don't experience that.

[T. Cotten]

Are you saying if I stop my bike and don't close the petcock my carb will overflow? I don't experience that.

Ain't you lucky, Bob!

The rest of us are victims of physics;

That's why petcocks were invented.

Floatvalves were designed to operate open.

...Cotten

[BigLakeBob]

I grind my needle tapers if needed then do a light lapping job, has worked well for me over the years. I couldn't imagine walking in a store for a few minutes and my carb overflowing.

[T. Cotten]

I grind my needle tapers if needed then do a light lapping job, has worked well for me over the years. I couldn't imagine walking in a store for a few minutes and my carb overflowing.

I stopped embedding abrasives in brass seats a quarter-century ago, Bob.

After inspection for obvious flaws, I usually just set the seat on a firm bench, placed the needle within it, and smacked it with a wooden screwdriver handle, and gave it the suck-test. Maybe twice. If three times failed, I sold it a new one. Schebs no problem.

Few minutes? Now you introduce the time factor?

...Cotten

[BigLakeBob]

Yea, I get it on the time factor, same with my job. Hobbies are different, time spent isn't time trying to make a living. I guess the seating the needle with a smack is like the oil pump ball seating. Thanks for all the tips.

[T. Cotten]

Yea, I get it on the time factor, same with my job. Hobbies are different, time spent isn't time trying to make a living. I guess the seating the needle with a smack is like the oil pump ball seating. Thanks for all the tips.

Its not about the job, Bob!

Its about spending too much time in the pub without worrying about it. I had no problem either.

Its about stinking up the garage over time, which means an OHV probably polluted its oil, and soaked its O-rings.

Petcocks are our friend when they work.

...Cotten

[Iacovos]

The service manual states to adjust the low speed needle out five full turns from lightly seated and that the motor will start but it will be rich. My recent experience doing this on a newly rebuilt 48EL is that five turns is WAY too rich and my plugs looked just like the ones in your photo. I discovered that about two turns instead of five did the trick. Of course this is just a starting point. If that fails then any of these other suggestions should be explored. Just my 2 cents . . .

Thanks Otis! I too believe that 5 turns is too much!

[dukekleman]

Lacovos,

Here's a guideline I'll share with you. It's in reference to the conversation regarding 5 turns on the low speed needle...

With all things working correctly, as engineered on the stock (as designed) motorcycle, your low speed needle should land at a final setting of 1 1/4 turns to a maximum of 2 1/2 turns when adjusted correctly at proper "operating temperature".

Any setting outside those boundaries indicates that you have an issue. That indication can be thought of like a check engine light of modern motorcycles, refered to as a malfunction indicator lamp today.

There are many things that drive the low speed calibration setting to be outside of its proper range. In an attempt to share this knowledge and keep things simple, please consider the range I stated above.

Hope this helps,
Duke Kleman

[Iacovos]

Lacovos,

Here's a guideline I'll share with you. It's in reference to the conversation regarding 5 turns on the low speed needle...

With all things working correctly, as engineered on the stock (as designed) motorcycle, your low speed needle should land at a final setting of 1 1/4 turns to a maximum of 2 1/2 turns when adjusted correctly at proper "operating temperature".

Any setting outside those boundaries indicates that you have an issue. That indication can be thought of like a check engine light of modern motorcycles, refered to as a malfunction indicator lamp today.

There are many things that drive the low speed calibration setting to be outside of its proper range. In an attempt to share this knowledge and keep things simple, please consider the range I stated above.

Hope this helps,
Duke Kleman

Hello Duke!

This is a great guideline!!

Will check asap and revert!