Plugs

1977 Kawasaki KZ650B
Specifications:
Front Tire Size Rear Tire Size Chain / Belt / Shaft Front Sprocket Rear Sprocket Battery Champion Spark Plug NGK Spark Plug
3.25x19 4.00x18 530x102 16T 42T YB10L-A2 No Data B7ES


Found this in the search files it states that b7es is correct plug.My shop manual says b8es.which should i use?

B7ES is stock. I believe B8ES is a colder plug. Either would probably be OK, I stay with the B7ES myself

Ron,I used B7ES myself becuase that what the spark plug book calls for but I was reading through my shop manual and noticed they keep refering to B8ES.Im having a hard start when cold isue and I got to wondering.Ill stick with B7ES then.Thank You!

That brings up an interesting point. The "first issue" (April 20, 1976) factory service manual called for the colder NGK B8ES or ND W24ES plugs. Later revised manuals (i.e. July '79 & Sept. '80) call for the hotter NGK B7ES or ND W22ES-U plugs. This is just a guess on my part, but I suspect that when the first edition was written most of the experience Kawasaki had was with bikes ridden by testers on a track (probably at full throttle). I'm guessing that by the time the later editions were printed there was more "real world" experience and they found the hotter plug was more appropriate for street use. I originally used the colder plugs, in fact, that what the factory originally shipped when my bike was built in December 1976, but I have found the hotter plug (I use the ND) helps when starting and warm-up when the engine is cold. Ed

Good point Ed,It also doesnt help that Im new at this and I tend to over anylize evrything.Specially becuase ive never set one of these things up before.

Heat Ranges are not the same between brands.



Go here for more on NGK Spark Plug Information:
www.ngksparkplugs.com/techinfo/spark_plu...nav=31000&country=US

Go here for NipponDenso Spark Plug Information:
www.in.net/~eholman/ndplugs.html

Go here for all Spark Plug Information:
www.sparkplugs.com/sparkplug411.asp

Post edited by: CoreyClough, at: 2007/11/02 07:34

Corey-Thanks yet agian sir!

Outstanding response Corey! This is one of the reasons I check this forum so often. I never understood the distribution of heat VS the location of the thermal mass. Good stuff! Thanks.

BTW BoZ650, my bike was very hard to start and very cold blooded. The major solution for me was the WG Coil Re-powering Mod. Was it done on your bike? Best of success.

Post edited by: bill_wilcox100, at: 2007/11/03 13:47

Bill,I have the coil mod all wired up but its currently not conected.I wired it so I can switch back to the stock set-up if needed and when I did the mod I couldnt get the bike to run at all.So I ordered the green dyna coils and the dyna-s ignition from Z1 Ent.When I get them Im gonna set it up with the coil mod at the same time.Its funny you said that cause I also suspected the coils/spark!Thanks again!