Author Topic: Spark plugs  (Read 1256 times)

0 Members and 1 Guest are viewing this topic.

Offline Dion

  • Full Member
  • *
  • Posts: 81
Spark plugs
« on: October 08, 2013, 12:27:37 PM »
Gents, what plugs do you recommend for a 836 sohc - with Cr29 carbs? It will be used for historic racing.

Offline Doctor_D

  • Hot Shot
  • ***
  • Posts: 722
Re: Spark plugs
« Reply #1 on: October 08, 2013, 04:57:02 PM »
Denso iridiums, IX27, made the most power in my 836.
Take care,
David
___________________________________________
1975 CB 750F - Project page: http://forums.sohc4.net/index.php?topic=66026.msg725479#msg725479
1978 CX500
1971 Norton Commando

Online scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,262
  • Humboldt, AZ
Re: Spark plugs
« Reply #2 on: October 08, 2013, 07:00:40 PM »
David, do you have a back-to-back dyno test with no changes other than the standard NGK plugs for the Densos?
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Doctor_D

  • Hot Shot
  • ***
  • Posts: 722
Re: Spark plugs
« Reply #3 on: October 08, 2013, 07:54:04 PM »
David, do you have a back-to-back dyno test with no changes other than the standard NGK plugs for the Densos?

Yes, and I have different heat ranges. Ix24 vs IX27.  Want to try the IX24b extended tip at some point... but there's only so much time.
Take care,
David
___________________________________________
1975 CB 750F - Project page: http://forums.sohc4.net/index.php?topic=66026.msg725479#msg725479
1978 CX500
1971 Norton Commando

Online scottly

  • Global Moderator
  • Really Old Timer ...
  • *****
  • Posts: 16,262
  • Humboldt, AZ
Re: Spark plugs
« Reply #4 on: October 08, 2013, 09:19:24 PM »
Please post the graphs you already have. (Dynos are cool! 8) 8))
Don't fix it if it ain't broke!
Helmets save brains. Always wear one and ride like everyone is trying to kill you....

Offline Doctor_D

  • Hot Shot
  • ***
  • Posts: 722
Re: Spark plugs
« Reply #5 on: October 08, 2013, 11:08:43 PM »
Please post the graphs you already have. (Dynos are cool! 8) 8))

Happy to.  I'll download the  data from the shop's dynojet this weekend.
Take care,
David
___________________________________________
1975 CB 750F - Project page: http://forums.sohc4.net/index.php?topic=66026.msg725479#msg725479
1978 CX500
1971 Norton Commando

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,531
  • Bike almost back to the 70's 2015
Re: Spark plugs
« Reply #6 on: October 09, 2013, 04:07:18 AM »
Denso iridiums, IX27, made the most power in my 836.

-What about NGK Iridiums? DR8EIX (6681)
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline trueblue

  • A person who has had many interesting experiences, some of which are true, is known as an
  • Old Timer
  • ******
  • Posts: 3,124
Re: Spark plugs
« Reply #7 on: October 09, 2013, 04:37:50 AM »
Please post the graphs you already have. (Dynos are cool! 8) 8))

Happy to.  I'll download the  data from the shop's dynojet this weekend.
I'm interested ;D
1979 CB650Z
Nothing can be idiot proofed, the world keeps producing better idiots.
Electronic Guages for your SOHC 4