Indexing spark plugs

I've indexed motorcycle plugs over the years with good results (especially on early BMW Oilheads which were usually too lean at part throttle no matter what you adjusted on a bone stock bike). What I don't know is how to correctly orient the electrodes in a turbo bike like our Secas. :?

 

I've been indexing the plugs on my bikes for a few years, it has made a noticeable improvement especially in the idle. I would index them with the open part of the plug facing directly in the middle of the combustion chamber. Thats where I put all mine and it works well. I don't have a turbo Seca but its worth a try.

 

I've read 3 somewhat contradictory theories -

Point the opening towards the intake, to clear a fresh charge.
Point the opening towards the piston, as the charge is compressed in during the compression stroke (makes sense)
Point the opening towards the exhaust valve, as the radiated heat helps keep the porcelain clean.

Well, that's 3 different directions.

So, I index so the ground strap is closest to the head, which seems to work well, all things considered.

 

can someone please explain what on earth you guys are talking about , I am lost

 

It's winter; and apparently some of us have nothing better to do. Even those of us who live in sunny climes and could be riding...

"Indexing" spark plugs refers to playing around with which point you start the plug threading into the head, and the final position you tighten it to, so that the orientation of the ground strap ends up in a THEORETICALLY advantageous position (as outlined by TIME, above) in relation to the combustion chamber.

The advantage to doing this, in real-world conditions, is debatable at best. SOME folks, and I won't go there, believe it to be complete hogwash except in F1 engines or the like. And those motors usually don't use "strap-grounded" plugs anyway.

Don't fret this one; just install your properly-gapped plugs to the proper torque and ride the bike. It's not a nitro-burning drag motor.

 

Wow, indexing plugs.

I have only ever bothered to do that on an engine that we blueprinted in a class that allowed almost no modifications, and we were looking for any gains possible. Only did it out of thoroughness and didn't notice any improvement.

Its been years since I have heard of anyone doing it.

 

I agree Fitz, indexing is really for race engines. There is really no benefit to doing it on the average street engine. Though I did notice a improved idle when I did my bikes. That was the only change I did.
Yes I was looking for something to do on a cold winter day several years ago.

 

Everything you need to know about INDEXING.

http://www.fordmuscle.com/archives/2000 ... ndex.shtml

Before you Index Spark Plugs looking for the ALLEGED Performance Gains, ...
you would need to:

Perform every Ignition Upgrade.
Replace OEM Ignition components with Aftermarket Performance Parts.
Eliminate every point of resistance which affects Ign Electrical Output.

Basically, ... When you have done everything there is to get the Maximum amount of Ponies the Plant is capable of making, ... there's one thing left you can try.

They have Scientific Data, Graphs and Illustrations to reinforce the processes legitimacy.

http://www.fordmuscle.com/archives/2000 ... ndex.shtml

http://www.urbandictionary.com/define.p ... 0stoned%29

 

"In real world conditions" is the key; especially as applies to 30 year old street bikes with watery ignition.

I'm sure there are indeed applications where it makes sense; ours isn't one of those.

 

Wow! Thanks for clarifying this one. I thought that I might need to park my bike and index plugs. Fitz and Rick saved me some time to ride.