Boxerworks.com

Spark Plugs?
Has anybody any experience with colortune spark plugs??
They have a glass body which allows you to see the color
of the burning fuel/air mixture which supposedly aids tuning??

Gunsen Colortune - I have one for the right side....



And one for the left side...



Not really that good, lawnmower technology - but good for doing a rough set up. With the Blue Magnum's once the needle is set, it's right for the rev range.

Bing sell them so they must think that they work.
I have a couple too, and they are excellent for setting the mixture screw the first time, but once you know where the correct spot is you shouldn't need them again.

They were more use on SU's, as the slow running adjustment sets the height of the needle jet, and consequently the mixture throughout the rev range. And you had a huge range of needles and quite a few springs you could try too.

I read somewhere that they could be used to check the mixture throughout the rev range by blocking the vehicule up on the centre stand/axle standss with the rear wheel of the ground, then running the motor against the rear brake.

Never tried it myself, I have this vision of the back wheel dropping down and the bike launching itself through the garage wall, but if you had a hard to find problem it might be a useful step / last resort in the elimination process.

There is a view that colourtunes on BMWs are off limited use, because the mixture burn on a standard model is so poor that the colourtunes gives poor results.

The mixture on all my bikes is just fine - I have no trouble getting the correct bunsen blue burn - but I have to adjust it the opposite way to the book to get it there.

That is, screwing the adjuster in richens it , and the best burn,and performance over about the first two yards, is just out from slowing on the way in.

Roy Gavin wrote:The mixture on all my bikes is just fine - I have no trouble getting the correct bunsen blue burn - but I have to adjust it the opposite way to the book to get it there.

That is, screwing the adjuster in richens it , and the best burn,and performance over about the first two yards, is just out from slowing on the way in.

I don't understand.

NGK and Dyna III runs great

As long as you do your own work so you'll not make the mistake of putting non-resistor plugs in one of the later Bosch systems then I think it fine to use non-resistor HT leads and caps with the easy to find NGK resistor plugs. Works for me.

John (itching to get going on my cross-US ride next month - leaving the day after attending my daughter"s Stanford graduation)

John Falconer wrote:As long as you do your own work so you'll not make the mistake of putting non-resistor plugs in one of the later Bosch systems then I think it fine to use non-resistor HT leads and caps with the easy to find NGK resistor plugs. Works for me.

John (itching to get going on my cross-US ride next month - leaving the day after attending my daughter"s Stanford graduation)

John, or whomever would like chime in, what does all of this talk about resistor plugs mean anyhow? My understanding of resistor anything in the ignition system was purely to stave off RF/EMI radiation - mainly into folks radios and I suppose now possible issues with on-board CPU's. For my education, could you let me in on the secret of your statement(s) above?

dwire wrote:

John Falconer wrote:As long as you do your own work so you'll not make the mistake of putting non-resistor plugs in one of the later Bosch systems then I think it fine to use non-resistor HT leads and caps with the easy to find NGK resistor plugs. Works for me.

John (itching to get going on my cross-US ride next month - leaving the day after attending my daughter"s Stanford graduation)

John, or whomever would like chime in, what does all of this talk about resistor plugs mean anyhow? My understanding of resistor anything in the ignition system was purely to stave off RF/EMI radiation - mainly into folks radios and I suppose now possible issues with on-board CPU's. For my education, could you let me in on the secret of your statement(s) above?

So what, no learning dope on the resistor plug/cap thing? Straining my head, I could only imagine other than what I posted as far as RF and EMI, is perhaps something to do with electronic ignition? Otherwise, the "good old" points system, really other than a tuned tank circuit, there is a capacitor (condenser) that keeps the arcing down of the breaker points contacts' - but I am still unsure why the combination, or even need aside from interfering with other things would arise for resistor plugs, caps or how the combination means anything - that is unless the resistance is too high to cross the gap and considering air is an OK resistor on its own; to say nothing of how its resistance skyrocketing under compression - something is still "a-miss" in my understanding. (Pun intended.)