K75 Plug Wire Layout

[Laitch]

Recent threads referring to spark plug wire routing compelled me to respond with a photo of the spark plug wire routing of my well-running '95 K75. The cylinders of a K75 are labeled 1-2-3 from front to rear. On my bike, cylinder 1 lead attaches to the coil closest to the head, cylinder 2 attaches to the middle coil and cylinder 3 to the rear coil. The incoming wires from the ECU to each coil on my bike are black/blue to front coil, black/red to the middle coil and black/green to the rear coil.

The Haynes manual asserts that the spark plugs' leads "must be correctly routed to prolong their service life." The Clymer instructs similarly. The text of both manuals has an underlying implication of doom if the routing isn't followed but both manuals have the muddiest halftones in creation coyly veiling the correct routing.

I don't know what the outcome is when the routing isn't followed. If somebody here can tell me from personal experience, please do. This routing works for my moto.

[K1300S]

mine. 

[K1300S]

nt

[Inge K.]

Laitch cables is correct routed, it's arranged in the same manner on 4cyl models also.
I would guess that the idea behind this routing is the one that gives less stress and kinks on the cables.

[Martin]

Laitch 16 years ago a BMW expert told me that if I didn't replace my NGK leads immediately that my computer would fail, and it would cost me $800.00, the earth would also open up and swallow me and my bike. He would however save me and my bike by selling me a set of OEM leads for the lowly price of $80.00 Au each. I have lived in fear for the last 120,000 K's and 16 years, I know I'm doomed. When my mate ordered a new set of NGK 5 Ohm leads of his Auto Electrician son I also purchased a set for the exorbitant price of $50.00 Au a set. That was six years ago and he is also doomed .
Regards Doomed Martin

[Laitch]

Well, lookee there, would ya. HOOWEEE! How about that? Amazing!

a BMW expert told me that if I didn't replace my NGK leads immediately that my computer would fail, and it would cost me $800.00, the earth would also open up and swallow me and my bike.

Maybe you're getting dispensation, Martin, because you've already been swallowed up by Australia. :giggles

[Inge K.]

16 years ago a BMW expert told me that if I didn't replace my NGK leads immediately that my computer would fail, and it would cost me $800.00, the earth would also open up and swallow me and my bike.

It looks like you follow the expert's advice....as you have a OEM cable intended for cyl. 3 connected to the
NGK cap at cyl. 1.

[Martin]

 I didn't notice that nicely spotted,  but his problem was with the NGK caps.Mate has run non OEM caps and wires no problem for 6 years. I have been told by quite a few experts that I should not run 5 Ohm NGK caps, and that I am doomed to live in purgatory for committing this sin. So be it, I like Hell it's nice and warm, and you meet some very interesting people here, and no pollies and lawyers allowed.  It also seems a lot better climate than what you guys are experiencing at the moment on the east coast.
A happily DOOMED Martin.

[Martin]

Inge that is the only marked lead, as stated I have another set. But as the saying goes if it ain't broke leave it alone. But over the years I have had multiple warnings to run OEM leads. I have yet to get a satisfactory explanation as to what happens if I don't change my leads. Could you or anybody please enlighten me.
A DOOMED and perplexed Martin.

[Laitch]

I would guess that the idea behind this routing is the one that gives less stress and kinks on the cables.

That makes sense, considering the dimensions of the wires, caps and fittings—a useful observation, Inge. I've just kept them like that through all the plug changes over the years, restraining any artistic longings I might have brought to the layout.

[WallaBeest]

When I put in new replacement spark plugs this weekend (Bosch from the fatherland), I indeed mixed the caps 2 and 3, with them temporarily on 3 and 2 (duh). I know it is b best just to addfress changing one plug any a time, but a friend wanted me to take a picture of old plugs and new lined up (indeed the Ngk's were the wrong length). Anyhows, with the caps in the wrong place, starting up sounded like a BANG BANG!! Okay, sure, I'll stop turning the ignition. Sure enough, the proper order is a blessing.

[The Mighty Gryphon]

Amazing how that works, isn't it?

The guy who works on the bikes in my garage made that same mistake.  Took him a whole evening to figure out what he did.

On another note.  Damn, I miss Inge.  He knew friggin' everything and was so cool about it. R.I.P.

[johnny]

sent inge a motobrick tshirt... asked him if he wanted me to send him weed... he said no... that the vikings had the best weed... sent him some humboldt county finest anyway...

he sent me this photo... that is an adult small shirt... he was small in size but his brain was enormous... 

inge drinking a beer with weed resin fingers... ha ha ha...



j o

[The Mighty Gryphon]

 

[frankenduck]

There can be differences in parts according to the model year.

All models and years of K75 use the same plug wires: 12121459874, 12121459875 and 12121459876.

I use Magnecor spark plug leads in many of my Ks.

[Laitch]

All models and years of K75 use the same plug wires: 12121459874, 12121459875 and 12121459876 I use Magnecor spark plug leads in many of my Ks.

The rider is in The Netherlands, duck; till.de. parts will work fine. Regarding posting the model year: doing that might help with queries about other parts. It seems like there are a lot of queries about those other ones here, too.   

[frankenduck]

The biggest model changes for K75s:

Early K75 standards had rear drum brake. Later had disc.

32A alternator up to 7/93, 50A after that.

Last couple years of K75RT had electric windscreen. Parts catalog doesn't have a date for this but a friend of mine had a 92 K75RT that had the electric windscreen.

[Laitch]

The biggest model changes . . .

How about the Showa fork assemblies? Not big enough? 

[frankenduck]

How about the Showa fork assemblies? Not big enough? 

Meh, you're correct.

3 kinds of forks: Original, "S" and Showa

Y-spoke vs. 3-spoke wheels

And ABS too!

[Past-my-Prime]

And the spline numbers changed sometime around 1988 or so?

[frankenduck]

And the spline numbers changed sometime around 1988 or so?

K75s always had 20.

85 and earlier K100s had 16.

[Laitch]

Meh . . .

You're correct. It's all meh . . . or as some would indicate, anicca. Nonetheless, it's helpful to readers if Brick owners who post here would put their moto's model and year in their Profile so it will show up with every post and let readers know exactly what they're working on when they come here gritting their teeth, tearing out their hair and wringing their hands. They'll also get an idea of some of the respondents' experience, too. When they read your curriculum vitae, they'll weep with joy, for their salvation is at hand.  When they read mine, I can hear the meh from beyond the horizon.