Author Topic: 650 heads  (Read 2943 times)

0 Members and 1 Guest are viewing this topic.

Offline bwaller

  • Really Old Timer ...
  • *******
  • Posts: 7,485
650 heads
« on: March 05, 2017, 12:04:47 PM »
Are there different inlet port spacings between CB650 heads. I know carbs changed but wonder about casting changes?

Thanks

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,058
Re: 650 heads
« Reply #1 on: March 05, 2017, 12:20:41 PM »
Yep, port spacing changed when they went to CV carbs.
 I have an NOS bare head to sell..I think its the later type have to check..
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline bwaller

  • Really Old Timer ...
  • *******
  • Posts: 7,485
Re: 650 heads
« Reply #2 on: March 05, 2017, 12:47:34 PM »
If anyone has both model heads I sure would appreciate a picture of both heads together intake ports up.

Not asking much huh?  ;D

Offline Camrector

  • Hot Shot
  • ***
  • Posts: 580
Re: 650 heads
« Reply #3 on: March 05, 2017, 01:40:53 PM »


PD50A stock '79cb650 carbs:
Type of carb                  - Mechanical linkage
depth (front to back)       -99.8mm
OD (motor side)              -35.4mm
OD (airbox side)              -45.8mm
#1&2 and 3&4 (c to c)     -76mm
between2&3  (c to c)      -80.9mm


VB44a stock '81 cb650 carbs:
Type of carb                  - CV
depth (front to back)       -122.1mm
OD (motor side)              -39.8mm
OD (airbox side)              -53.8mm
#1&2 and 3&4 (c to c)     -66.3mm
between2&3  (c to c)      -92.7mm



Offline cb650

  • Old Timer
  • ******
  • Posts: 3,864
Re: 650 heads
« Reply #4 on: March 05, 2017, 05:07:26 PM »
Yes 81 / 2 went with a wider spacing on the head to accommodate the carbs. I was told the DOHC 750 uses the same carb with diff jets.    Some one years ago did some work to find how to make them interchange.  seemed like a lot of work to not get the right carbs
18 grand and 18 miles dont make you a biker

Offline GV1390

  • Hot Shot
  • ***
  • Posts: 586
  • Express Gratitude.
Re: 650 heads
« Reply #5 on: March 06, 2017, 06:49:17 AM »
If anyone has both model heads I sure would appreciate a picture of both heads together intake ports up.

Not asking much huh?  ;D



You're welcome.

 ;)
93' GSX-R1100, 78' CB550, 71' CL350, 71’ CB500 & 02' ZRX1200R.

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,564
  • Big ideas....
Re: 650 heads
« Reply #6 on: March 06, 2017, 06:52:50 AM »
That looks familiar ;D
Owner of the "Million Dollar CB"

Offline bwaller

  • Really Old Timer ...
  • *******
  • Posts: 7,485
Re: 650 heads
« Reply #7 on: March 06, 2017, 01:16:19 PM »
Thanks guys, that works.

Offline BLAC

  • An espresso is a
  • Hot Shot
  • ***
  • Posts: 694
Re: 650 heads
« Reply #8 on: March 07, 2017, 02:21:08 PM »
That looks familiar ;D

You've been to GV's shop?  jk :P
If you can't fix it with a hammer, it's an electrical problem... If it's an electrical problem, it's Cal's problem.

*2005 Yamaha R6 (sold)
*2014 Ducati Streetfighter 848 (sold)
*2014 BMW S1000RR (sold)
*2010 Ducati Streetfighter S
*1978 CB550 Restomod Build
*1974 CB550 Monoshock build
http://forums.sohc4.net/index.php/topic,154614.0.html

Offline SOHC4 Cafe Racer Fan

  • Speak up, Whipper-Snapper! I'm a
  • Really Old Timer ...
  • *******
  • Posts: 15,731
  • SOHC/4 Member #1235
Re: 650 heads
« Reply #9 on: March 07, 2017, 04:15:13 PM »
That looks familiar ;D

You've been to GV's shop?  jk :P

Oh!
I think your head is going to take a little longer now! ;)
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline BLAC

  • An espresso is a
  • Hot Shot
  • ***
  • Posts: 694
Re: 650 heads
« Reply #10 on: March 08, 2017, 08:16:56 AM »
That looks familiar ;D

You've been to GV's shop?  jk :P

Oh!
I think your head is going to take a little longer now! ;)

I KID I KID!!!!  ;D
If you can't fix it with a hammer, it's an electrical problem... If it's an electrical problem, it's Cal's problem.

*2005 Yamaha R6 (sold)
*2014 Ducati Streetfighter 848 (sold)
*2014 BMW S1000RR (sold)
*2010 Ducati Streetfighter S
*1978 CB550 Restomod Build
*1974 CB550 Monoshock build
http://forums.sohc4.net/index.php/topic,154614.0.html

Offline bwaller

  • Really Old Timer ...
  • *******
  • Posts: 7,485
Re: 650 heads
« Reply #11 on: March 08, 2017, 09:28:28 AM »
Someone helped Mike get the pics up for me. You're not in hot water!