Spark Plug Issues

[AussieSteve]

You need to keep in mind, Fabian, as we've pointed out in the past, that your case is an exception to the rule. (Buggered if I know why.)
Most of these engines would 4-stroke all of the time with a jet that size.

What colour is your plug?

 

[Fabian]

Plug colour is dark chocolate brown.

Fabian

 

[AussieSteve]

I run mine a little lighter, but still, that doesn't sound bad.
(It's still got me stuffed how your's works properly on such a large jet.)

 

[jarz24]

the one i got in the kit has a pin end and this one has a oval end will it still work?

heres a photo of the one i bought

http://www.1977mopeds.com/product/338

and this it a stock one

http://www.kingsmotorbikes.com/bike-motor-part-spark-plug-m4x-125.html

 

[AussieSteve]

jarz24, you can get a B6HS at any SCA or AutoOne store, or just about any other auto accessory dealer. No need to order off the web and pay additional postage.

You need to unscrew the top screw-cap off the new B6HS. Don't try to fit it without doing that or you'll possibly damage the clip in the plug cap.

 

[jarz24]

thank you so when i go into a store just ask for a b6hs spark plug theres no brand name?

 

[GearNut]

Ngk B6hs

 

[Fabian]

You can also try to get the NGK BP6HS
The BP6HS is a B6HS with a projector nose plug tip.

I prefer the BP6HS as it moves the firing tip further away from the cylinder head wall, and to a more central location in the combustion chamber.

Fabian

 

[Alson]

Spsrk p,ug issues

Well thanks for letting me know, about the jet,I did put the bigger one that was for this new carb, the float level mad a big differance, it runs good, now my slide sticks sometimes, Im working on it now. Is a light tan colar plug all right. Oh ya I thought the 66cc stock jet was #70 and they said the new stile carb was a little biger, what ever that may be

 

[AussieSteve]

New style carb has an 0.79mm, Alson. (Many of the older ones were, as you say, 0.7mm. A little lean. I think that they decided to go richer, but over-did it enormously.)

Fabian, how much further does the BP6HS extend into the combustion chamber than a B6HS?
The reason I ask is that with the RSE billet head, there's only 1.1mm clearance between piston and plug tang.
Do you reckon a BP6HS might hit? How much longer is it? I might need to be wary in the future.