Print Page - 250/400 Spark Plugs

Title: 250/400 Spark Plugs
Post by: Kip Kern on October 01, 2002, 09:39:23 AM

Any recommendations for spark plugs for the 73/74 250's and the 74 400 would be greatly appreciated. Bikes will be used as museum pieces, "putters" not racers. Would like to stay away from Champion if possible. Thanks

Title: 250/400 Spark Plugs
Post by: fischercycle on October 01, 2002, 10:02:11 AM

Hi, Kip I have the bosch 260 through 310 half 1nch reach maybe that will help, also the champion gold platinum also the baru 240 to 310 same as bosch the pink one.also good to see your still involved. JAKE FISCHER

Title: 250/400 Spark Plugs
Post by: Dave Withrow on October 01, 2002, 10:04:50 AM

Kip,
I've been running NGK B9HS plugs as a standard plug and B8HS when I needed a hotter plug. My '74 400 does well with them.

Title: 250/400 Spark Plugs
Post by: Kip Kern on October 01, 2002, 12:37:42 PM

Thanks Guy's, I appreciate the feedback, it is always nice to be able to count on friends!

Title: 250/400 Spark Plugs
Post by: tlanders on October 01, 2002, 12:45:58 PM

Kip,

I thought that the NGK B8HS plugs was the standard ( Barry Higgens) except for the Mint 400 which should use a B9HS, I read somewhere, opposite to what Dave said. I have been using the B8EG plugs however for racing. They have a much stronger spark but they are long reach. So I put 1/2" high spacers between the plug and the head to make the long reach plugs end up at the same point in the cylinder as the short reach ones do. At first I was concerned about the fact that I only have one plug gasket between the plug and the spacer and there is none between the spacer and the head, but so far I haven't had any leaks. Sure wish I could remember where I read about the colder plug for the 400.

Teddy

Title: 250/400 Spark Plugs
Post by: Steve Minor on October 01, 2002, 12:53:04 PM

Don't know if it helps or hinders, but my Penton owner's manual that says Bosch W-290 for the Mint 400.......

Title: 250/400 Spark Plugs
Post by: tlanders on October 01, 2002, 01:32:02 PM

DUH - Dave did say the B9HS was standard for the Mint 400. I read his message wrong. Sorry Dave.

Teddy

Title: 250/400 Spark Plugs
Post by: Knute on October 05, 2002, 01:26:06 AM

Hey Guys,

I spoke with an engineer at NGK at the beginning of this race season and he recommended their VX series of plugs. These are NGK's best motorcycle plugs, featuring a "fine wire platinum center electrode and a tapered ground electrode" for maximum efficiency, making them ideal for older ignition systems as well. I used the B8HVX in our 250 and 400 race bikes and didn't change a plug all season.

As far as originality goes, one of my old manuals mentions the Bosch W 290 T 16. Would this have been the original plug Kip?

Kent

Title: 250/400 Spark Plugs
Post by: Kip Kern on October 05, 2002, 09:54:25 PM

I think that is correct Kent. The old Bosch numbers are no longer available, they changed all of their numbers to new ones, I'll have to recheck the changes!

Title: 250/400 Spark Plugs
Post by: Kip Kern on October 06, 2002, 07:45:26 PM

OK, Bosch W3AC or NGK B8HS = 100/125 Penton
Bosch W3AS or NGK B8HV = 175/250/400 Penton

This is what I found so far!

Title: 250/400 Spark Plugs
Post by: tlanders on October 06, 2002, 08:57:10 PM

What's the difference between HS and HV? Teddy

Title: 250/400 Spark Plugs
Post by: Frenfroe on October 06, 2002, 09:12:43 PM

H=short reach
S=standard electrode
V=fine electrode (platinum)
and
VX=new super fine electrode

Title: 250/400 Spark Plugs
Post by: tlanders on October 06, 2002, 09:37:26 PM

Thanks. Our local cycle shop thinks the B8EG is the best plug for racing and doesn't like the platinum ones. I wonder what the difference is between the VX and G?

Penton Owners Group

General Discussion => Penton Talk => Topic started by: Kip Kern on October 01, 2002, 09:39:23 AM