SPARK PLUGS BOSCH

One thing that I forgot to mention was to stay away from the fancy plugs like Platinum or Iridium. You would be paying a lot of money for absolutely no benefit. Stay with either Copper core or with Silver core and with full electrode with. Do not use any of the ones with the thin electrodes.

The Denso plugs that were the best plugs ever made for these bikes were the #4030 (W24ES-U) They give the best Life, Efficiency, Power, and all around general performance. They were more expensive than the NGK plug and therefore not used from the factory. However they were listed as the optional plug by Kawasaki. The NGK plug dose not come close to the Denso (ND) plug. This is the reason I made the investment and bought so many f them. There is NO SUBSTITUTE. They are by far the best. The only other plug that I have found that even comes close to the Denso "Hot-U" plugs are the German Made "Beru" "Silverstone" plugs, #S7. I just don't like to spend $9 per plug. Here is a link to a previous post we did about this.
kzrider.com/index.php?option=com_kunena&...ew&catid=4&id=351334

No eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationNo eBay APP ID and/or Cert ID defined in Kunena configurationLet the bidding begin!

Set of 3.


Set of 4. (Does not say "new", but shows boxes.)


One.

Odd...I have use Bosch in cars with no issue. I usually use Autolite, though.

Only use NGK in my bikes.

I don't even like putting Champions in my lawnmower, had nothing but bad luck with them.

When I used to race back in the late 70s and early 80s we tested all kinds of plugs and the B8ES plugs were the first thing we threw away and replaced with ND (now Denso) plugs. As new and more modern stuff came out we tested that stuff, but always wound up back with the ND W24ES-u plugs. I used to have couple of friends that worked for BOSCH and I was able to get almost anything I wanted for FREE. Nothing survived. My neighbor who has a foreign car repair service, also refuses to use BOSCH components due to their poor track record. He told me he just cant afford to replace parts multiple times for free due to failure. That gos for ALL electrical components, such as Sensors, Plugs, Injectors and so on.

I googled and found a few sources for the w24es-u. Now you have me interested.

I used to live in Kaneohe and race at Industrial park.

otakar wrote:

I used to live in Kaneohe and race at Industrial park.

Campbell Industrial's race park closed a few years ago. H-3 was a good place to go fast for several years and then the cops started tagging people there.

Let me know if you make a trip back to Hawaii!

Aloha, Mike

I bought that set of Denso plugs on E-bay. Looking forward to trying them out.

If you are running stock coils than gap them at .030-.035" If you are using aftermarket coils, such as Dyna, than gap them between .045"-.060" I run mine at .060" with Dyna gray 2.2 Ohm coils. Once I install the MSD box i will open them to .080". Use this link as a guide.

kzrider.com/index.php?option=com_kunena&...ew&catid=4&id=351334

That brings up another question (coils). I am trying to figure out what works with my bike. It has a Dyna S ignition and stock coils. I believe the Dyna green coils will work with it, right?

And I have read about removing the resistor. Where is the resistor located?

Thanks

Kapahulu wrote:

...Dyna S ignition and stock coils. I believe the Dyna green coils will work with it...have read about removing the resistor. Where is the resistor located?....

Here's the obscure pic from FSM, but shows general location, and the text notes colors of wires involved (i.e., red and pink).

Good Fortune!

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