R3 Spark Plugs

[TxRIIIRider]

I had Splitfires in my Thunderbird Sport and it ran like a scalded a$$ ape. I can't narrow down any performance increase to the Splitfires since I also went with a K&N filter, jet changes, and aftermarket exhaust at same time (Originally, this project was to fix the starter, but since I had to remove the air filter box and carbs to gain easy access to the starter, this justified the other mods... don't ya think??). But, I had put them in at 12,500 miles and the bike had 39,000 miles on it when I sold it and was still great. I miss that bike!.. I'm sure there are much better plugs now on the market. I'll come back to this thread when I have to change plugs on the Rocket..

 

[busajack]

index

Yes it's me, Mr. Negativity with my 2cents. Indexing plugs on a street vehicle is a waste of time and money.(ck. the price of indexing washers at Jegs or someplace like that.)You need all the diferent sizes.(thickness)to do it right, then just a little over torquing and it won't be right.Yes if u have an indy car that turns 18000 RPM I am sure it would make a difference.I used to do it with street rods till it almost drove me nuts (maybe it did) Tomo is right that it can be used more for plug reading than anything else. Jack

 

[Hondax]

Indexing sounds like something that could help my single cylinder bikes and for that matter all outdoor power sports.

My question: Do you add a washer on top of the original "crush washer" or do the index washers replace same?

Next question: If a washer is needed to index a plug can the added distance away from the top of the piston warrant a hotter plug or is the change to minute to worry about?

Another question: It I indexed my Rocket and ended up with different indexing washer thicknesses between the three cylinders would it cause any operating irregularities, or again, would the thickness differences be moot?

 

[Toystoretom]

1. Add washer(s) to the existing crush washer (If it has a crush washer, some plugs don't).

2. Don't use a hotter plug....Plug reach isn't going to be that much different..

3. Once again... plug reach isn't going to be that much different. You only need to add enough thickness to take up 1/2 thread (Or less) on the spark plug, a very small distance in the greater scheme of things...

 

[Sidecar Flip]

3. Once again... plug reach isn't going to be that much different. You only need to add enough thickness to take up 1/2 thread (Or less) on the spark plug, a very small distance in the greater scheme of things...

That is where you might encounter some problems. Like Tomo says, a very small distance. Basically measured in thousands of a inch. The washer would have to be thick enough to not split under torque but the correct size to allow the plug to sit in the correct position. You'd almost have to take a stock flat washer with the correct i.d and machine it to the proper thickness. Just grabbing a flat washer, using it without adjusting the thickness would be a crap shoot. There is only one practical way to machine something that thin and that's attach it to a magnetic chuck and grind it.

 

[busajack]

washers

Yo Flip: Just guessing but aren't most plug washers copper.?Jegs has all the thickneses u could need.U could always hold them in your fingers and hit them with a 36 grit body grinder disk.LOL